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1.  Effect of Statins on Venous Thromboembolic Events: A Meta-analysis of Published and Unpublished Evidence from Randomised Controlled Trials 
PLoS Medicine  2012;9(9):e1001310.
A systematic review and meta-analysis conducted by Kazem Rahimi and colleagues re-evaluates the hypothesis, generated in previous studies, that statins may reduce the risk of venous thromboembolic events. Their meta-analysis does not support the previous findings.
Background
It has been suggested that statins substantially reduce the risk of venous thromboembolic events. We sought to test this hypothesis by performing a meta-analysis of both published and unpublished results from randomised trials of statins.
Methods and Findings
We searched MEDLINE, EMBASE, and Cochrane CENTRAL up to March 2012 for randomised controlled trials comparing statin with no statin, or comparing high dose versus standard dose statin, with 100 or more randomised participants and at least 6 months' follow-up. Investigators were contacted for unpublished information about venous thromboembolic events during follow-up. Twenty-two trials of statin versus control (105,759 participants) and seven trials of an intensive versus a standard dose statin regimen (40,594 participants) were included. In trials of statin versus control, allocation to statin therapy did not significantly reduce the risk of venous thromboembolic events (465 [0.9%] statin versus 521 [1.0%] control, odds ratio [OR] = 0.89, 95% CI 0.78–1.01, p = 0.08) with no evidence of heterogeneity between effects on deep vein thrombosis (266 versus 311, OR 0.85, 95% CI 0.72–1.01) and effects on pulmonary embolism (205 versus 222, OR 0.92, 95% CI 0.76–1.12). Exclusion of the trial result that provided the motivation for our meta-analysis (JUPITER) had little impact on the findings for venous thromboembolic events (431 [0.9%] versus 461 [1.0%], OR = 0.93 [95% CI 0.82–1.07], p = 0.32 among the other 21 trials). There was no evidence that higher dose statin therapy reduced the risk of venous thromboembolic events compared with standard dose statin therapy (198 [1.0%] versus 202 [1.0%], OR = 0.98, 95% CI 0.80–1.20, p = 0.87). Risk of bias overall was small but a certain degree of effect underestimation due to random error cannot be ruled out.
Please see later in the article for the Editors' Summary.
Conclusions
The findings from this meta-analysis do not support the previous suggestion of a large protective effect of statins (or higher dose statins) on venous thromboembolic events. However, a more moderate reduction in risk up to about one-fifth cannot be ruled out.
Editors' Summary
Background
Blood normally flows smoothly throughout the human body, supplying its organs and tissues with oxygen and nutrients. But, when an injury occurs, proteins called clotting factors make the blood gel (coagulate) at the injury site. The resultant blood clot (thrombus) plugs the wound and prevents blood loss. Occasionally, however, a thrombus forms inside an uninjured blood vessel and partly or completely blocks the blood flow. A clot inside one of the veins (vessels that take blood towards the heart) deep within the body is called a deep vein thrombosis (DVT). Symptoms of DVT (which usually occurs in the leg) include pain, swelling, and redness in the affected limb. DVT is treated with heparin and warfarin, two anticoagulant drugs that stop the blood clot growing. If left untreated, part of the clot (an embolus) can break off and travel to the lungs, where it can cause a pulmonary embolism (PE), a life-threatening condition characterized by chest pain, breathlessness, coughing, and dizziness. Little is known about how to prevent DVTs and PEs but risk factors for these venous thromboembolic events include having an inherited blood clotting disorder, oral contraceptive use, having surgery, and prolonged inactivity (on long-haul plane flights, for example).
Why Was This Study Done?
In 2009, a secondary (add-on) analysis of data from a randomized controlled trial (RCT, a study that randomly assigns individuals to receive different treatments and compares the outcomes associated with each treatment) called the JUPITER trial reported that rosuvastatin—a cholesterol-lowering drug (statin)—halved the risk of venous thromboembolic events among apparently healthy adults. The JUPITER trial was initiated to test whether statins reduce the risk of strokes, heart attacks, and other cardiovascular diseases (conditions that involve the heart and the blood vessels) among adults with raised levels of a predictor for these diseases called C-reactive protein; statins reduce the levels of this protein as well as those of cholesterol. Because fewer than 100 of the participants in the JUPITER trial developed a DVT or PE, the reduction in the risk of a venous thromboembolic event among the participants who took rosuvastatin could have happened by chance. In this systematic review and meta-analysis of 29 RCTs of statins that collected information on many more venous thromboembolic events, the researchers test the hypothesis that statins substantially reduce the risk of such events. A systematic review uses predefined criteria to identify all the research on a given topic; a meta-analysis is a statistical approach that combines the results of several studies.
What Did the Researchers Do and Find?
The researchers identified 22 RCTs (105,759 participants) that compared the effects of statins with control (dummy) tablets and seven (40,594 participants) that compared an intensive statin regimen with a standard regimen. They then obtained largely unpublished information about the venous thromboembolic events that occurred during these trials (about 1,000 DVTs and PEs) from the original investigators. In the trials of statin versus control, allocation to statin therapy did not significantly reduce the risk of venous thromboembolic events. Thus, although events occurred in 465 participants who were given statins (0.9% of the participants) and in 521 participants who were given control tablets (1% of the participants), this difference in outcomes was not statistically significant—it could have happened by chance. Exclusion of the JUPITER trial results from the meta-analysis did not alter this finding. The researchers also found no evidence that intensive statin therapy reduced the risk of venous thromboembolic events compared to standard therapy.
What Do These Findings Mean?
The findings of this meta-analysis do not support the suggestion that statins, either at the standard dose or at higher doses, reduce the risk of venous thromboembolic events substantially among healthy adults. It is possible that the effect of statins has been underestimated in this meta-analysis because of missing data or because of some other source of bias. Furthermore, because the total number of events in this meta-analysis is still relatively modest, these findings do not rule out the possibility that statins may reduce the risk of venous thromboembolic events by up to about one-fifth in some or all individuals. Additional large RCTs are now needed to investigate whether statin treatment does in fact reduce the risk of venous thromboembolic events in adults and, if it does, whether all statins have a similar effect and whether statin treatment is beneficial in everyone or only in specific subgroups of people.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001310.
This study is further discussed in a PLOS Medicine Perspective by Frits Rosendaal
The US National Heart Lung and Blood Institute provides information on deep vein thrombosis (including an animation about how DVT causes pulmonary embolisms), and information on pulmonary embolism
The UK National Health Service Choices website has information on deep vein thrombosis, including personal stories, on pulmonary embolism, and on statins; a Behind the Headlines article describes the JUPITER trial and its implications
The non-profit organization US National Blood Clot Alliance provides detailed information about deep vein thrombosis and pulmonary embolism for patients and professionals and includes a selection of personal stories about these conditions
MedlinePlus has links to further information about deep vein thrombosis, pulmonary embolism, and statins (in English and Spanish)
doi:10.1371/journal.pmed.1001310
PMCID: PMC3445446  PMID: 23028261
2.  Statins in the Treatment of Chronic Heart Failure: A Systematic Review 
PLoS Medicine  2006;3(8):e333.
Background
The efficacy of statin therapy in patients with established chronic heart failure (CHF) is a subject of much debate.
Methods and Findings
We conducted three systematic literature searches to assess the evidence supporting the prescription of statins in CHF. First, we investigated the participation of CHF patients in randomized placebo-controlled clinical trials designed to evaluate the efficacy of statins in reducing major cardiovascular events and mortality. Second, we assessed the association between serum cholesterol and outcome in CHF. Finally, we evaluated the ability of statin treatment to modify surrogate endpoint parameters in CHF.
Using validated search strategies, we systematically searched PubMed for our three queries. In addition, we searched the reference lists from eligible studies, used the “see related articles” feature for key publications in PubMed, consulted the Cochrane Library, and searched the ISI Web of Knowledge for papers citing key publications.
Search 1 resulted in the retrieval of 47 placebo-controlled clinical statin trials involving more than 100,000 patients. CHF patients had, however, been systematically excluded from these trials. Search 2 resulted in the retrieval of eight studies assessing the relationship between cholesterol levels and outcome in CHF patients. Lower serum cholesterol was consistently associated with increased mortality. Search 3 resulted in the retrieval of 18 studies on the efficacy of statin treatment in CHF. On the whole, these studies reported favorable outcomes for almost all surrogate endpoints.
Conclusions
Since CHF patients have been systematically excluded from randomized, controlled clinical cholesterol-lowering trials, the effect of statin therapy in these patients remains to be established. Currently, two large, randomized, placebo-controlled statin trials are under way to evaluate the efficacy of statin treatment in terms of reducing clinical endpoints in CHF patients in particular.
A systematic review found that patients with heart failure have been excluded from randomised controlled trials on the use of statins. Evidence from other studies on the effectiveness of statins for patients with heart failure is weak and conflicting.
Editors' Summary
Background.
When medical researchers test a drug—or some other treatment—for a particular medical condition, they often decide not to include in their study anyone who has, in addition to the disease they are interested in, certain other health problems. This is because including patients with two or more conditions can complicate the analysis of the results and make it hard to reach firm conclusions. However, excluding patients in this way can result in uncertainty as to whether treatments are effective for anyone who suffers from the disease in question, or just for people like those who took part in the research.
A great deal of research has been conducted with drugs known as statins, which lower cholesterol levels in the blood. (A raised level of cholesterol is known to be a major risk factor for cardiovascular disease, which causes heart attacks and strokes.) As a result of this research, statins have been accepted as effective and safe. They are now, in consequence, among the most commonly prescribed medicines. Heart failure, however, is not the same thing as a heart attack. It is the name given to the condition where the muscles of the heart have become weakened, most often as a result of aging, and the heart becomes gradually less efficient at pumping blood around the body. (Some people with heart failure live for many years, but 70% of those with the condition die within ten years.) It is common for people with cardiovascular disease also to have heart failure. Nevertheless, some researchers who have studied the effects of statins have made the decision not to include in their studies any patients with cardiovascular disease who, in addition, have heart failure.
Why Was This Study Done?
The researchers in this study were aware that patients with heart failure have often been excluded from statin trials. They felt it was important to assess the available evidence supporting the prescription of statins for such patients. Specifically, they wanted to find out the following: how often have patients with heart failure been included in statin trials, what evidence is available as to whether it is beneficial for patients with heart failure to have low cholesterol, and what evidence is there that prescribing statins helps these patients?
What Did the Researchers Do and Find?
They did not do any new work involving patients. Instead, they did a very thorough search for all relevant studies of good quality that had already been published and they reviewed the results. “Randomized clinical trials” (RCTs) are the most reliable type of medical research. The researchers found there had been 47 such trials (involving over 100,000 patients) on the use of statins for treating cardiovascular disease, but all these trials had excluded heart failure patients. They found eight studies (which were not RCTs) looking at cholesterol levels and heart failure. These studies found, perhaps surprisingly, that death rates were higher in those patients with heart failure who had low cholesterol. However, they also found 18 studies (again not RCTs) on the use of statins in patients with heart failure. These 18 studies seemed to suggest that statins were of benefit to the patients who received them.
What Do These Findings Mean?
The evidence for or against prescribing statins for people with heart failure is limited, conflicting, and unclear. Further research involving RTCs is necessary. (Two such trials are known to be in progress.)
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0030333.
General information about statins is available from the Web site of Patient UK
The American Heart Association Web site is a good source of information about all types of heart disease, including heart attacks and heart failure
For a definition of randomized controlled trials see Wikipedia, a free online encyclopedia that anyone can edit
More detailed information about the quality of evidence from medical research may be found in the James Lind Library
doi:10.1371/journal.pmed.0030333
PMCID: PMC1551909  PMID: 16933967
3.  Statins Impair Antitumor Effects of Rituximab by Inducing Conformational Changes of CD20 
PLoS Medicine  2008;5(3):e64.
Background
Rituximab is used in the treatment of CD20+ B cell lymphomas and other B cell lymphoproliferative disorders. Its clinical efficacy might be further improved by combinations with other drugs such as statins that inhibit cholesterol synthesis and show promising antilymphoma effects. The objective of this study was to evaluate the influence of statins on rituximab-induced killing of B cell lymphomas.
Methods and Findings
Complement-dependent cytotoxicity (CDC) was assessed by MTT and Alamar blue assays as well as trypan blue staining, and antibody-dependent cellular cytotoxicity (ADCC) was assessed by a 51Cr release assay. Statins were found to significantly decrease rituximab-mediated CDC and ADCC of B cell lymphoma cells. Incubation of B cell lymphoma cells with statins decreased CD20 immunostaining in flow cytometry studies but did not affect total cellular levels of CD20 as measured with RT-PCR and Western blotting. Similar effects are exerted by other cholesterol-depleting agents (methyl-β-cyclodextrin and berberine), but not filipin III, indicating that the presence of plasma membrane cholesterol and not lipid rafts is required for rituximab-mediated CDC. Immunofluorescence microscopy using double staining with monoclonal antibodies (mAbs) directed against a conformational epitope and a linear cytoplasmic epitope revealed that CD20 is present in the plasma membrane in comparable amounts in control and statin-treated cells. Atomic force microscopy and limited proteolysis indicated that statins, through cholesterol depletion, induce conformational changes in CD20 that result in impaired binding of anti-CD20 mAb. An in vivo reduction of cholesterol induced by short-term treatment of five patients with hypercholesterolemia with atorvastatin resulted in reduced anti-CD20 binding to freshly isolated B cells.
Conclusions
Statins were shown to interfere with both detection of CD20 and antilymphoma activity of rituximab. These studies have significant clinical implications, as impaired binding of mAbs to conformational epitopes of CD20 elicited by statins could delay diagnosis, postpone effective treatment, or impair anti-lymphoma activity of rituximab.
Jakub Golab and colleagues found that statins significantly decrease rituximab-mediated complement-dependent cytotoxicity and antibody-dependent cellular cytotoxicity against B cell lymphoma cells.
Editors' Summary
Background.
Lymphomas are common cancers of the lymphatic system, the tissues and organs that produce and store the white blood cells (lymphocytes) that fight infections. In healthy people, the cells in the lymph nodes (collections of lymphocytes in the armpit, groin, and neck) and other lymphatic organs divide to form new cells only when the body needs them. Lymphomas form when a T or B lymphocyte starts to divide uncontrollably. The first sign of lymphoma is often a painless swelling in the armpit, groin, or neck caused by lymphocyte overgrowth in a lymph node. Eventually, the abnormal (malignant) lymphocytes, which provide no protection against infectious diseases, spread throughout the body. Treatments for lymphoma include chemotherapy (drugs that kill rapidly dividing cells) and radiotherapy. In addition, a drug called rituximab was recently developed for the treatment of some types of B cell lymphoma. Rituximab is a monoclonal antibody, a laboratory-produced protein. It binds to a protein called CD20 that is present on the surface of both normal and malignant B lymphocytes and induces cell killing through processes called “complement-dependent cytotoxity” (CDC) and “antibody-dependent cellular cytotoxity” (ADCC).
Why Was This Study Done?
Although rituximab lengthens the lives of patients with some types of B cell lymphoma, it is not a cure—the lymphoma usually recurs. Researchers are trying to increase the effectiveness of rituximab by combining it with other anticancer agents. One group of drugs that might be combined with rituximab is the “statins,” drugs that reduce the risk of heart disease by lowering the level of cholesterol (a type of fat) in the blood. In laboratory experiments, statins kill some cancer cells, in part by altering the fat composition of their outer (plasma) membrane. In addition, some population-based studies suggest that statin treatment might slightly decrease the risk of developing some kinds of cancer, including lymphoma. Statins are already undergoing clinical evaluation in combination with chemotherapy for the treatment of lymphoma, but in this study, the researchers investigate the influence of statins on rituximab-induced killing of B cell lymphomas.
What Did the Researchers Do and Find?
When the researchers tested the ability of rituximab and statin combinations to kill B cell lymphoma cells growing in dishes, they found that statins decreased rituximab-dependent CDC and ADCC of these cells. Statin treatment, they report, did not alter the total amount of CD20 made by the lymphoma cells or the amount of CD20 in their plasma membranes, but it did reduce the binding of another anti-CDC20 monoclonal antibody to the cells. Because both this antibody and rituximab bind to a specific three-dimensional structure in CD20 (a “conformational epitope”), the researchers hypothesized that statins might alter rituximab-induced killing by affecting the shape of the CD20 molecule on the lymphoma cell surface. To test this idea, they used two techniques—atomic force microscopy and limited proteolysis. The data obtained using both approaches confirmed that statins induce shape changes in CD20. Finally, the researchers took B cells from five patients who had taken statins for a short time and showed that this treatment had reduced the amount of anti-CD20 monoclonal antibody able to bind to these cells.
What Do These Findings Mean?
These findings indicate that statins change the shape of the CD20 molecules on the surface of normal and malignant B lymphocytes, probably by changing the amount of cholesterol in the cell membrane. This effect of statins has several clinical implications, which means that cancer specialists should check whether patients with known or suspected B cell lymphoma are taking statins to treat high cholesterol. First, the impaired binding of monoclonal antibodies to conformational epitopes of CD20 in patients being treated with statins might delay the diagnosis of B cell lymphomas (CD20 binding to lymphocytes is used during the diagnosis of lymphomas). Second, some patients with B cell lymphoma may receive an incorrect diagnosis and may not be offered rituximab. Finally, because statins impair the anti-lymphoma activity of rituximab, a possibility that needs to be investigated in clinical studies, cancer specialists should check that patients with B cell lymphoma are not taking statins before prescribing rituximab.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0050064.
The MedlinePlus has an encyclopedia page on lymphoma and a list of links to other sources of information on lymphoma (in English and Spanish)
The US National Cancer Institute provides information about lymphoma and about statins and cancer prevention (in English and Spanish)
The UK charity Cancerbackup provides information for patients and caregivers on different types of B-cell lymphoma and on rituximab
The US Leukemia and Lymphoma Society also provides information for patients and caregivers about lymphoma
doi:10.1371/journal.pmed.0050064
PMCID: PMC2270297  PMID: 18366248
4.  Personalized Prediction of Lifetime Benefits with Statin Therapy for Asymptomatic Individuals: A Modeling Study 
PLoS Medicine  2012;9(12):e1001361.
In a modeling study conducted by Myriam Hunink and colleagues, a population-based cohort from Rotterdam is used to predict the possible lifetime benefits of statin therapy, on a personalized basis.
Background
Physicians need to inform asymptomatic individuals about personalized outcomes of statin therapy for primary prevention of cardiovascular disease (CVD). However, current prediction models focus on short-term outcomes and ignore the competing risk of death due to other causes. We aimed to predict the potential lifetime benefits with statin therapy, taking into account competing risks.
Methods and Findings
A microsimulation model based on 5-y follow-up data from the Rotterdam Study, a population-based cohort of individuals aged 55 y and older living in the Ommoord district of Rotterdam, the Netherlands, was used to estimate lifetime outcomes with and without statin therapy. The model was validated in-sample using 10-y follow-up data. We used baseline variables and model output to construct (1) a web-based calculator for gains in total and CVD-free life expectancy and (2) color charts for comparing these gains to the Systematic Coronary Risk Evaluation (SCORE) charts. In 2,428 participants (mean age 67.7 y, 35.5% men), statin therapy increased total life expectancy by 0.3 y (SD 0.2) and CVD-free life expectancy by 0.7 y (SD 0.4). Age, sex, smoking, blood pressure, hypertension, lipids, diabetes, glucose, body mass index, waist-to-hip ratio, and creatinine were included in the calculator. Gains in total and CVD-free life expectancy increased with blood pressure, unfavorable lipid levels, and body mass index after multivariable adjustment. Gains decreased considerably with advancing age, while SCORE 10-y CVD mortality risk increased with age. Twenty-five percent of participants with a low SCORE risk achieved equal or larger gains in CVD-free life expectancy than the median gain in participants with a high SCORE risk.
Conclusions
We developed tools to predict personalized increases in total and CVD-free life expectancy with statin therapy. The predicted gains we found are small. If the underlying model is validated in an independent cohort, the tools may be useful in discussing with patients their individual outcomes with statin therapy.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Cardiovascular disease (CVD) affects the heart and/or the blood vessels and is a major cause of illness and death worldwide. In the US, for example, coronary heart disease—a CVD in which narrowing of the heart's blood vessels by fatty deposits slows the blood supply to the heart and may eventually cause a heart attack—is the leading cause of death, and stroke—a CVD in which the brain's blood supply is interrupted—is the fourth leading cause of death. Established risk factors for CVD include smoking, high blood pressure, obesity, and high blood levels of a fat called low-density lipoprotein (“bad cholesterol”). Because many of these risk factors can be modified by lifestyle changes and by drugs, CVD can be prevented. Thus, physicians can assess a healthy individual's risk of developing CVD using a CVD prediction model (equations that take into account the CVD risk factors to which the individual is exposed) and can then recommend lifestyle changes and medications to reduce that individual's CVD risk.
Why Was This Study Done?
Current guidelines recommend that asymptomatic (healthy) individuals whose likely CVD risk is high should be encouraged to take statins—cholesterol-lowering drugs—as a preventative measure. Statins help to prevent CVD in healthy people with a high predicted risk of CVD, but, like all medicines, they have some unwanted side effects, so it is important that physicians can communicate both the benefits and drawbacks of statins to their patients in a way that allows them to make an informed decision about taking these drugs. Telling a patient that statins will reduce his or her short-term risk of CVD is not always helpful—patients really need to know the potential lifetime benefits of statin therapy. That is, they need to know how much longer they might live if they take statins. Here, the researchers use a mathematical model to predict the personalized lifetime benefits (increased total and CVD-free life expectancy) of statin therapy for individuals without a history of CVD.
What Did the Researchers Do and Find?
The researchers used the Rotterdam Ischemic Heart Disease & Stroke Computer Simulation (RISC) model, which simulates the life courses of individuals through six health states, from well through to CVD or non-CVD death, to estimate lifetime outcomes with and without statin therapy in a population of healthy elderly individuals. They then used these outcomes and information on baseline risk factors to develop a web-based calculator suitable for personalized prediction of the lifetime benefits of statins in routine clinical practice. The model estimated that statin therapy increases average life expectancy in the study population by 0.3 years and average CVD-free life expectancy by 0.7 years. The gains in total and CVD-free life expectancy associated with statin therapy increased with blood pressure, unfavorable cholesterol levels, and body mass index (an indicator of body fat) but decreased with age. Notably, the web-based calculator predicted that some individuals with a low ten-year CVD risk might achieve a similar or larger gain in CVD-free life expectancy with statin therapy than some individuals with a high ten-year risk. So, for example, both a 55-year-old non-smoking woman with a ten-year CVD mortality risk of 2% (a two in a hundred chance of dying of CVD within ten years) and a 65-year-old male smoker with a ten-year CVD mortality risk of 15% might both gain one year of CVD-free life expectancy with statin therapy.
What Do These Findings Mean?
These findings suggest that statin therapy can lead on average to small gains in total life expectancy and slightly larger gains in CVD-free life expectancy among healthy individuals, and show that life expectancy benefits can be predicted using an individual's risk factor profile. The accuracy and generalizability of these findings is limited by the assumptions included in the model (in particular, the model did not allow for the known side effects of statin therapy) and by the data fed into it—importantly, the risk prediction model needs to be validated using an independent dataset. If future research confirms the findings of this study, the researchers' web-based calculator could provide complementary information to the currently recommended ten-year CVD mortality risk assessment. Whether communication of personalized outcomes will ultimately result in better clinical outcomes remains to be seen, however, because patients may be less likely to choose statin therapy when provided with more information about its likely benefits.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001361.
The web-based calculator for personalized prediction of lifetime benefits with statin therapy is available (after agreement to software license)
The American Heart Association provides information about many types of cardiovascular disease for patients, carers, and professionals, including information about drug therapy for cholesterol and a heart attack risk calculator
The UK National Health Service Choices website provides information about cardiovascular disease and about statins
Information is available from the British Heart Foundation on heart disease and keeping the heart healthy; information is also available on statins, including personal stories about deciding to take statins
The US National Heart Lung and Blood Institute provides information on a wide range of cardiovascular diseases
The European Society of Cardiology's cardiovascular disease risk assessment model (SCORE) is available
MedlinePlus provides links to many other sources of information on heart diseases, vascular diseases, stroke, and statins (in English and Spanish)
doi:10.1371/journal.pmed.1001361
PMCID: PMC3531501  PMID: 23300388
5.  The Effect of Alternative Summary Statistics for Communicating Risk Reduction on Decisions about Taking Statins: A Randomized Trial 
PLoS Medicine  2009;6(8):e1000134.
Carling and colleagues carry out a trial evaluating different methods of communicating information to people regarding the risks and benefits of taking statins. They suggest that natural frequencies are likely to be the most appropriate summary statistic for presenting the effects of treatment.
Background
While different ways of presenting treatment effects can affect health care decisions, little is known about which presentations best help people make decisions consistent with their own values. We compared six summary statistics for communicating coronary heart disease (CHD) risk reduction with statins: relative risk reduction and five absolute summary measures—absolute risk reduction, number needed to treat, event rates, tablets needed to take, and natural frequencies.
Methods and Findings
We conducted a randomized trial to determine which presentation resulted in choices most consistent with participants' values. We recruited adult volunteers who participated through an interactive Web site. Participants rated the relative importance of outcomes using visual analogue scales (VAS). We then randomized participants to one of the six summary statistics and asked them to choose whether to take statins based on this information. We calculated a relative importance score (RIS) by subtracting the VAS scores for the downsides of taking statins from the VAS score for CHD. We used logistic regression to determine the association between participants' RIS and their choice. 2,978 participants completed the study. Relative risk reduction resulted in a 21% higher probability of choosing to take statins over all values of RIS compared to the absolute summary statistics. This corresponds to a number needed to treat (NNT) of 5; i.e., for every five participants shown the relative risk reduction one additional participant chose to take statins, compared to the other summary statistics. There were no significant differences among the absolute summary statistics in the association between RIS and participants' decisions whether to take statins. Natural frequencies were best understood (86% reported they understood them well or very well), and participants were most satisfied with this information.
Conclusions
Presenting the benefits of taking statins as a relative risk reduction increases the likelihood of people accepting treatment compared to presenting absolute summary statistics, independent of the relative importance they attach to the consequences. Natural frequencies may be the most suitable summary statistic for presenting treatment effects, based on self-reported preference, understanding of and satisfaction with the information, and confidence in the decision.
Clinical Trials Registration
ISRCTN85194921
Please see later in the article for the Editors' Summary
Editors' Summary
Background
People often have to make decisions about their health care. Ideally, all the health care decisions that a person makes should be those best suited to his or her personal circumstances and expectations. Take, for example, someone with a high amount of cholesterol (a type of fat) in his or her blood. Because this condition increases the chances of developing potentially fatal coronary heart disease (CHD), such a person will often be advised by his or her doctor to take statins to reduce blood cholesterol levels. However, the person needs to consider both the benefits and downsides of this course of action. Can he or she afford to pay for statins, if their health care system requires him or her to? Does the person want to take a pill every day that might cause some side effects? That is, the person has to consider his or her “values”—the relative desirability of all the possible outcomes of taking statins—before deciding whether to follow his or her doctor's advice.
Why Was This Study Done?
It is well known that how information is presented to patients about treatment options and their consequences affects the choices that they make. For example, patients who are told that a drug will halve their chances of developing a disease (a 50% relative risk reduction) are more likely to decide to take that drug than those who are told it will reduce their absolute (actual) risk of developing the disease from 4% to 2%. Less is known, however, about which presentations of treatment effects best help people to make decisions that are consistent with their own values. In 2002, therefore, a series of internet-based randomized trials (studies in which participants are randomly allocated to different “treatment” groups) called the Health Information Project: Presentation Online (HIPPO) was initiated. Here, the researchers describe HIPPO 2, a trial that investigates how alternative summary statistics for communicating the reduction of CHD risk with statins affect people's decisions to take statins.
What Did the Researchers Do and Find?
Nearly 3,000 adults in Norway and North America rated the relative importance to them of CHD risk reduction, the cost of statins, and the need to take a daily pill through an interactive Web site. The researchers used these data to calculate a “relative importance score” (RIS), an indicator of each participant's values. Each participant then decided whether or not to take statins after being shown one of six summary statistics about the effect of statins on CHD risk (relative risk reduction and five indicators of absolute risk reduction). The presentation of the effect of statins as a relative risk reduction resulted in more people deciding to take statins over the whole RIS range than any of the absolute summary statistics. For every five participants shown the relative risk reduction statistic, an extra participant chose to take statins compared to the other summary statistics. When asked to compare the six summary statistics, the statistic that most people preferred and understood best was the “natural frequency,” an absolute summary statistic that gave the number of people likely to develop CHD with and without statin treatment.
What Do These Findings Mean?
Although these findings may not be generalizable to other populations or to other medical decisions, they provide new insights into how the presentation of information can affect the choices people make about health care. Specifically, these findings indicate that the presentation of the reduced risk of getting CHD as a result of taking stains as a relative amount is more likely to persuade people to take statins than several absolute summary statistics. They also suggest that the persuasive effect of the relative risk reduction summary statistic is not affected by the relative importance attached to the consequences of taking statins by individuals. That is, people shown the relative risk reduction statistic may be more likely to start statins to reduce their CHD risk (or a drug that reduces the risk of developing another disease) whatever their personal values than people shown absolute summary statistics. Finally, the findings on participant preferences suggest that natural frequencies may be the best summary statistic to include in tools designed to help people make decisions about their healthcare.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000134.
A PLoS Medicine Editorial discusses this trial and the results of another HIPPO trial that are presented in a separate PLoS Medicine Research Article by Carling and colleagues; details of a pilot HIPPO trial are also available
The Foundation for Informed Medical Decision Making (a US-based non-profit organization) provides information on many aspects of medical decision making
The Dartmouth-Hitchcock Medical Center provides information to help people make health care decisions through its Center for Shared Decision Making
The Ottawa Hospital Research Institute provides also information on patient decision aids, including an inventory of decision aids available on the Web (in English and French)
MedlinePlus provides links to information and advice about statins and about coronary heart disease (in English and Spanish)
doi:10.1371/journal.pmed.1000134
PMCID: PMC2724738  PMID: 19707575
6.  Possible modification of Alzheimer’s disease by statins in midlife: interactions with genetic and non-genetic risk factors 
The benefits of statins, commonly prescribed for hypercholesterolemia, in treating Alzheimer’s disease (AD) have not yet been fully established. A recent randomized clinical trial did not show any therapeutic effects of two statins on cognitive function in AD. Interestingly, however, the results of the Rotterdam study, one of the largest prospective cohort studies, showed reduced risk of AD in statin users. Based on the current understanding of statin actions and AD pathogenesis, it is still worth exploring whether statins can prevent AD when administered decades before the onset of AD or from midlife. This review discusses the possible beneficial effects of statins, drawn from previous clinical observations, pathogenic mechanisms, which include β-amyloid (Aβ) and tau metabolism, genetic and non-genetic risk factors (apolipoprotein E, cholesterol, sex, hypertension, and diabetes), and other clinical features (vascular dysfunction and oxidative and inflammatory stress) of AD. These findings suggest that administration of statins in midlife might prevent AD in late life by modifying genetic and non-genetic risk factors for AD. It should be clarified whether statins inhibit Aβ accumulation, tau pathological features, and brain atrophy in humans. To answer this question, a randomized controlled study using amyloid positron emission tomography (PET), tau-PET, and magnetic resonance imaging would be useful. This clinical evaluation could help us to overcome this devastating disease.
doi:10.3389/fnagi.2014.00071
PMCID: PMC4005936  PMID: 24795626
statin; Alzheimer’s disease; prevention; Abeta; isoprenoids
7.  Persistence with Statins and Onset of Rheumatoid Arthritis: A Population-Based Cohort Study 
PLoS Medicine  2010;7(9):e1000336.
In a retrospective cohort study, Gabriel Chodick and colleagues find a significant association between persistence with statin therapy and reduced risk of developing rheumatoid arthritis, but only a modest decrease in risk of osteoarthritis.
Background
The beneficial effects of statins in rheumatoid arthritis (RA) have been suggested previously, but it is unclear whether statins may prevent its development. The aim of this retrospective cohort study was to explore whether persistent use of statins is associated with onset of RA.
Methods and Findings
The computerized medical databases of a large health organization in Israel were used to identify diagnosed RA cases among adults who began statin therapy between 1998 and 2007. Persistence with statins was assessed by calculating the mean proportion of follow-up days covered (PDC) with statins for every study participant. To assess the possible effects of healthy user bias, we also examined the risk of osteoarthritis (OA), a common degenerative joint disease that is unlikely to be affected by use of statins.
A total of 211,627 and 193,770 individuals were eligible for the RA and OA cohort analyses, respectively. During the study follow-up period, there were 2,578 incident RA cases (3.07 per 1,000 person-years) and 17,878 incident OA cases (24.34 per 1,000 person-years). The crude incidence density rate of RA among nonpersistent patients (PDC level of <20%) was 51% higher (3.89 per 1,000 person-years) compared to highly persistent patients who were covered with statins for at least 80% of the follow-up period. After adjustment for potential confounders, highly persistent patients had a hazard ratio of 0.58 (95% confidence interval 0.52–0.65) for RA compared with nonpersistent patients. Larger differences were observed in younger patients and in patients initiating treatment with high efficacy statins. In the OA cohort analysis, high persistence with statins was associated only with a modest decrement in risk ratio (hazard ratio = 0.85; 0.81–0.88) compared to nonadherent patients.
Conclusions
The present study demonstrates an association between persistence with statin therapy and reduced risk of developing RA. The relationship between continuation of statin use and OA onset was weak and limited to patients with short-term follow-up.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
The role of statins in the management of diseases that have an inflammatory component is unclear. There is some evidence that statins may have anti-inflammatory and immunumodulatory properties, demonstrated by reducing the level of C-reactive protein that may play an important role in chronic inflammatory diseases, such as rheumatoid arthritis—a chronic condition that is a major cause of disability. Some small studies have suggested a modest effect of statins in decreasing disease activity in patients with rheumatoid arthritis, but a recent larger study involving over 30,000 patients with rheumatoid arthritis showed no beneficial effect. Furthermore, it has been suggested that statins may have a role in the primary prevention of rheumatoid arthritis, but so far there has been no solid evidence base to support this hypothesis. Before statins can potentially be included in the treatment options for rheumatoid arthritis, or possibly prescribed for the prevention of this condition, there needs to be a much stronger evidence base, such as larger studies with longer follow-up periods, which clearly demonstrates any significant clinical benefits of statin use.
Why Was This Study Done?
This large study (more than 200,000 patients) with a long follow-up period (average of 10 years) was conducted to discover whether there was any kind of association between persistent use of statins and the onset of rheumatoid arthritis.
What Did the Researchers Do and Find?
The researchers conducted a retrospective cohort study among the members of Maccabi Healthcare Services (a health maintenance organization [HMO]) in Israel, which has 1.8-million enrollees and covers every section of the Israeli population, to identify statin users who were at least 18 years of age and did not have RA or a related disease at study entry. The cohort covered the period 1998–2007 and included members who were continuously enrolled in the HMO from 1995 to 1998. The researchers then analyzed the incidence of newly diagnosed rheumatoid arthritis, recording the date of first diagnostic codes (International Classification of Diseases, 9th revision [ICD-9]) associated with rheumatoid arthritis during the study follow-up period. To assess any potential effects of “healthy adherer” bias (good adherence to medication in patients with a chronic illness may be more likely to lead to better health and improved survival), the researchers also examined any possible association between persistent statin use and the development of osteoarthritis, a common degenerative joint disease that is unlikely to be affected by statin use.
During the study follow-up period, there were 2,578 incident cases of rheumatoid arthritis and 17,878 incident cases of osteoarthritis. The crude incidence density rate of rheumatoid arthritis among patients who did not persistently take statins was 51% higher than that of patients who used statins for at least 80% of the follow-up period. Furthermore, patients who persistently used statins had a risk ratio of 0.58 for rheumatoid arthritis compared with patients who did not persistently use statins. In the osteoarthritis cohort analysis, high persistence with statin use was associated with a modest decrement in risk ratio (0.85) compared to patients who did not persist with statins.
What Do These Findings Mean?
This study suggests that there is an association between persistence with statin therapy and reduced risk of developing rheumatoid arthritis. Although the researchers took into account the possibility of healthy adherer bias (by comparing results with the osteoarthritis cohort), this study has other limitations, such as the retrospective design, and the nonrandomization of statin use, which could affect the interpretation of the results. However, the observed associations were greater than those that would be expected from methodological biases alone. Larger, systematic, controlled, prospective studies with high efficacy statins, particularly in younger adults who are at increased risk for rheumatoid arthritis, are needed to confirm these findings and to clarify the exact nature of the biological relationship between adherence to statin therapy and the incidence of rheumatoid arthritis.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000336.
Arthritis Research UK provides a wide range of information on arthritis research
The American College of Rheumatology provides information on rheumatology research
Patient information on rheumatoid arthritis is available at Patient UK
Extensive information about statins is available at statin answers
doi:10.1371/journal.pmed.1000336
PMCID: PMC2935457  PMID: 20838658
8.  Molecular sources of residual cardiovascular risk, clinical signals, and innovative solutions: relationship with subclinical disease, undertreatment, and poor adherence: implications of new evidence upon optimizing cardiovascular patient outcomes 
Residual risk, the ongoing appreciable risk of major cardiovascular events (MCVE) in statin-treated patients who have achieved evidence-based lipid goals, remains a concern among cardiologists. Factors that contribute to this continuing risk are atherogenic non-low-density lipoprotein (LDL) particles and atherogenic processes unrelated to LDL cholesterol, including other risk factors, the inherent properties of statin drugs, and patient characteristics, ie, genetics and behaviors. In addition, providers, health care systems, the community, public policies, and the environment play a role. Major statin studies suggest an average 28% reduction in LDL cholesterol and a 31% reduction in relative risk, leaving a residual risk of about 69%. Incomplete reductions in risk, and failure to improve conditions that create risk, may result in ongoing progression of atherosclerosis, with new and recurring lesions in original and distant culprit sites, remodeling, arrhythmias, rehospitalizations, invasive procedures, and terminal disability. As a result, identification of additional agents to reduce residual risk, particularly administered together with statin drugs, has been an ongoing quest. The current model of atherosclerosis involves many steps during which disease may progress independently of guideline-defined elevations in LDL cholesterol. Differences in genetic responsiveness to statin therapy, differences in ability of the endothelium to regenerate and repair, and differences in susceptibility to nonlipid risk factors, such as tobacco smoking, hypertension, and molecular changes associated with obesity and diabetes, may all create residual risk. A large number of inflammatory and metabolic processes may also provide eventual therapeutic targets to lower residual risk. Classically, epidemiologic and other evidence suggested that raising high-density lipoprotein (HDL) cholesterol would be cardioprotective. When LDL cholesterol is aggressively lowered to targets, low HDL cholesterol levels are still inversely related to MCVE. The efflux capacity, or ability to relocate cholesterol out of macrophages, is believed to be a major antiatherogenic mechanism responsible for reduction in MCVE mediated in part by healthy HDL. HDL cholesterol is a complex molecule with antioxidative, anti-inflammatory, anti-thrombotic, antiplatelet, and vasodilatory properties, among which is protection of LDL from oxidation. HDL-associated paraoxonase-1 has a major effect on endothelial function. Further, HDL promotes endothelial repair and progenitor cell health, and supports production of nitric oxide. HDL from patients with cardiovascular disease, diabetes, and autoimmune disease may fail to protect or even become proinflammatory or pro-oxidant. Mendelian randomization and other clinical studies in which raising HDL cholesterol has not been beneficial suggest that high plasma levels do not necessarily reduce cardiovascular risk. These data, coupled with extensive preclinical information about the functional heterogeneity of HDL, challenge the “HDL hypothesis”, ie, raising HDL cholesterol per se will reduce MCVE. After the equivocal AIM-HIGH (Atherothrombosis Intervention in Metabolic Syndrome With Low HDL/High Triglycerides: Impact on Global Health Outcomes) study and withdrawal of two major cholesteryl ester transfer protein compounds, one for off-target adverse effects and the other for lack of efficacy, development continues for two other agents, ie, anacetrapib and evacetrapib, both of which lower LDL cholesterol substantially. The negative but controversial HPS2-THRIVE (the Heart Protection Study 2-Treatment of HDL to Reduce the Incidence of Vascular Events) trial casts further doubt on the HDL cholesterol hypothesis. The growing impression that HDL functionality, rather than abundance, is clinically important is supported by experimental evidence highlighting the conditional pleiotropic actions of HDL. Non-HDL cholesterol reflects the cholesterol in all atherogenic particles containing apolipoprotein B, and has outperformed LDL cholesterol as a lipid marker of cardiovascular risk and future mortality. In addition to including a measure of residual risk, the advantages of using non-HDL cholesterol as a primary lipid target are now compelling. Reinterpretation of data from the Treating to New Targets study suggests that better control of smoking, body weight, hypertension, and diabetes will help lower residual risk. Although much improved, control of risk factors other than LDL cholesterol currently remains inadequate due to shortfalls in compliance with guidelines and poor patient adherence. More efficient and greater use of proven simple therapies, such as aspirin, beta-blockers, angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers, combined with statin therapy, may be more fruitful in improving outcomes than using other complex therapies. Comprehensive, intensive, multimechanistic, global, and national programs using primordial, primary, and secondary prevention to lower the total level of cardiovascular risk are necessary.
doi:10.2147/VHRM.S37119
PMCID: PMC3808150  PMID: 24174878
cardiovascular prevention; low-density lipoprotein; high-density lipoprotein; statin drugs; metabolic syndrome; obesity; diabetes; niacin; AIM-HIGH study; cholesteryl ester transfer protein; endothelial progenitor cells; fibrate drugs
9.  Cholesterol and Statins in Alzheimer’s Disease 
Archives of neurology  2011;68(11):1385-1392.
Substantial evidence has accumulated in support of the hypothesis that elevated cholesterol levels increase the risk of developing Alzheimer’s disease (AD). As a result, much work has been done investigating the potential use of lipid-lowering agents (LLAs), particularly statins, as preventive or therapeutic agents for AD. While epidemiology and preclinical statin research (described in Part 1 of this review) have generally supported an adverse role of high cholesterol regarding AD, human studies of statins (reviewed here) show highly variable outcomes, making it difficult to draw firm conclusions. We identify several confounding factors among the human studies, including differing blood-brain barrier permeabilities among statins, the stage in AD at which statins were administered, and the drugs’ pleiotropic metabolic effects, all of which contribute to the substantial variability observed to date. We recommend that future human studies of this important therapeutic topic 1) take the blood-brain barrier permeabilities of statins into account when analyzing results, 2) include specific analyses of effects on low-density and high-density lipoprotein cholesterol, and most importantly, 3) conduct statin treatment trials solely in mild AD patients, who have the best chance for disease modification.
doi:10.1001/archneurol.2011.242
PMCID: PMC3248784  PMID: 22084122
10.  The use of statins in primary prevention  
Background
The use of statins in secondary prevention of cardiovascular events is well established. However, there is ongoing discussion about the use of statins in the context of primary prevention. Moreover statins - besides cholesterol-lowering effects - are assumed to have pleiotropic effects. Positive impacts on diseases like stroke, Alzheimer's disease or osteoporosis are discussed but still have to be proven.
Objectives
The aim of this report is first to investigate the efficacy and effectiveness of statins in primary prevention of cardiovascular and non-cardiovascular events and second to examine the economic implications for Germany - particularly in comparison to existing prevention programs. Finally ethical questions are considered.
Methods
A systematic literature search was performed for the period between 1998 and 2004 which yielded 3704 abstracts. Overall 43 articles were included for assessment and 167 for background information, according to predefined selection criteria.
Results
Most studies within the context of primary prevention describe significant risk reductions with regard to cardiovascular events; yet no significant results according to the reduction of the overall mortality rate can be seen. With respect to stroke, osteoporosis and Alzheimer's disease results are inconsistent. Regarding cost-effectiveness of primary prevention with statins results turn out to be inconsistent as well or even negative for populations with low to moderate risk. For groups with high cardiovascular risk the intervention is mostly assessed to be cost-effective. No cost-effectiveness study for Germany was found. According to a rough estimate of future expenses statin drug expenses of the German legal health insurance might increase at least by 50% in the case of an enlargement of the group of recipients.
Discussion
To thoroughly estimate the cost-effectiveness of the use of statins in primary prevention in Germany a model calculation including all relevant parameters has to be done. Moreover - from the economic as well as from the ethic point of view - one of the most important issues in primary prevention therapy is the question of compliance. The amount of risk reduction seen in primary prevention studies can be achieved only if patients as well as doctors follow therapeutic instructions and medical guidelines (as for example the guidelines of the "Adult Treatment Panel III", the "European guidelines on cardiovascular disease prevention in clinical practice" or the guidelines of the German Association of Cardiology and of the "Arzneimittelkommission der deutschen Ärzteschaft für Koronare Herzkrankheit").
Conclusion
For (primary) prevention of cardiovascular diseases the use of statins as suggested in guidelines is recommended - provided that these guidelines are scientifically evaluated at regular intervals. Regarding stroke, osteoporosis and Alzheimer's disease definite conclusions cannot be drawn at present. Particular attention has to be paid to the problem of compliance both in statin-therapy as well as in alternative therapies. The cost-effectiveness of primary prevention with statins mainly depends on the development of statin prices.
PMCID: PMC3011349  PMID: 21289961
11.  Role of Colesevelam in Combination Lipid-Lowering Therapy 
Hyperlipidemia is associated with an increased risk of cardiovascular events; reducing low-density lipoprotein cholesterol (LDL-C), the primary target for cholesterol-lowering therapy, lowers the risk for such events. Although bile acid sequestrants were the first class of drugs to show a mortality benefit related to LDL-C lowering, statins are now considered first-line pharmacological therapy for reducing LDL-C levels because of their potency and their remarkable record of successful outcomes studies. Nevertheless, a substantial proportion of patients do not achieve LDL-C goals with statin monotherapy. In addition, because of adverse effects (primarily myopathy), some patients may be unwilling to use or unable to tolerate statin therapy at all or may not tolerate a full therapeutic statin dose. Also, statins may increase risk of new-onset diabetes in patients at high risk for diabetes. Thus, there remains a need for other lipid-lowering drugs to be used in combination with or in place of statins. The purpose of this article is to review available data from the literature on the use of colesevelam, a second-generation bile acid sequestrant, in combination with other lipid-lowering agents. Colesevelam has been studied in combination with statins, niacin, fibrates, and ezetimibe (including some three-drug combinations). An additive reduction in LDL-C was seen with all combinations. Other observed effects of colesevelam in combination with other lipid-lowering drugs include reductions in apolipoprotein (apo) B (with statins, fibrates, ezetimibe, statin plus niacin, or statin plus ezetimibe) and high-sensitivity C-reactive protein (with statins), and increases in apo A-I (with statins, ezetimibe, or statins plus niacin). Triglyceride levels remained relatively unchanged when colesevelam was combined with statins, fibrates, ezetimibe, or statin plus ezetimibe, and decreased with the triple combination of colesevelam, statin, and niacin. Colesevelam offset the negative glycemic effects of statins and niacin in subjects with insulin resistance or impaired glucose tolerance. Colesevelam was generally well tolerated when added to other lipid-lowering therapies in clinical trials, with gastrointestinal effects such as constipation being the predominant adverse events. Since colesevelam is not absorbed and works primarily in the intestine, it has a low potential for systemic metabolic drug–drug interactions with other drugs. Colesevelam has been shown to not interact with the lipid-lowering drugs lovastatin and fenofibrate; where interaction may be anticipated, separating dosing times by 4 h reduces the impact of any interaction. Available data confirms that colesevelam has additive cholesterol-lowering effects when used in combination with other lipid-lowering therapies. Furthermore, in some patient populations, the additional glucose-lowering effect of colesevelam may be beneficial in offsetting hyperglycemic effects of other lipid-lowering drugs.
doi:10.1007/s40256-013-0037-0
PMCID: PMC3781306  PMID: 23913404
12.  Statins and prostate cancer: role of cholesterol inhibition vs. prevention of small GTP-binding proteins 
Prostate cancer (PCa) is initially regulated by androgens, such as testosterone and dihydrotestosterone, which regulates cell proliferation and survival by activating the androgen receptor (AR), but later progresses to an aggressive, metastatic, androgen-independent stage for which, currently, there is no cure. Here, we argue that prevention of PCa progression is a better strategy compared to trying to cure the disease once it has already progressed. Statins inhibit the mevalonate pathway, thus preventing the synthesis of cholesterol, geranylgeranyl pyrophosphate and farnesyl pyrophosphate. Multiple clinical studies have shown an inverse relationship between statin use and PCa risk, especially the risk for developing advanced metastatic cancer. Biochemical investigations have largely corroborated the positive effect of statins on PCa risk, showing that statins inhibited cell proliferation, induced apoptosis, and decreased cell migration and invasion in PCa cells in vitro. However, investigations of the biochemical mechanism of statin action in preventing advanced/high risk PCa remains inconclusive, as statins can act through cholesterol, geranylgeranyl, or farnesyl mediated signals. This review discusses the current clinical and biochemical findings on the use of statins in preventing PCa. Evidence of statin action through cholesterol as well as geranylgeranylation and farnesylation has been discussed. As cholesterol is a precursor of androgen production, it can reduce PCa risk by decreasing the levels of circulating testosterone, which in turn reduces the levels of interprostatic dihydrotestosterone, a strong ligand for the AR. Cholesterol was also shown to accumulate in lipid rafts and regulate the activation of the phosphatidylinositol 3-kinase/Akt pathway. However, clinical evidence from multiple studies also point to the existence of cholesterol-independent pathways mediating statin action in PCa patients. In particular, ligand-activated AR activation is seen in early stage PCa and activation of the cholesterol pathway did not indicate an effect on metastasis. Cell migration and invasion, on the other hand, is regulated strongly by members of the Ras superfamily of small GTPases, especially the Rho family, which is geranylgeranylated. This review, therefore, also compares the effects of statins on both cholesterol and geranylgeranylated and farnesylated small GTPases regulating tumor progression and metastasis in biochemical and clinical studies.
PMCID: PMC3186052  PMID: 21984972
Mevalonate pathway; cholesterol; geranylgeranyl pyrophosphate; farnesyl pyrophosphate; Akt; androgen receptor; metastasis; Ras; Rac; Rho
13.  Diabetes: managing dyslipidaemia 
Clinical Evidence  2008;2008:0610.
Introduction
Dyslipidaemia is a major contributor to the increased risk of heart disease found in people with diabetes. An increase of 1 mmol/L LDL-C is associated with a 1.57-fold increase in the risk of coronary heart disease (CHD) in people with type 2 diabetes. A diagnosis of diabetic dyslipidaemia requiring pharmacological treatment is determined by the person's lipid profile and level of cardiovascular risk.
Methods and outcomes
We conducted a systematic review and aimed to answer the following clinical question: What are the effects of interventions for dyslipidaemia in people with diabetes? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2007 (BMJ Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
Results
We found 21 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
Conclusions
In this systematic review we present information relating to the effectiveness and safety of the following interventions: anion exchange resins, combined treatments (for lipid modification), ezetimibe, fibrates, fish oil (for lipid modification), intensive multiple intervention treatment programmes (for lipid modification), nicotinic acid (for lipid modification), and statins.
Key Points
Dyslipidaemia is characterised by decreased circulating levels of high-density lipoprotein cholesterol (HDL-C) and increased circulating levels of triglycerides and low-density lipoprotein cholesterol (LDL-C). Dyslipidaemia is a major contributor to the increased risk of heart disease found in people with diabetes.An increase of 1 mmol/L LDL-C is associated with a 1.57-fold increase in the risk of CHD in people with type 2 diabetes.A diagnosis of diabetic dyslipidaemia requiring pharmacological treatment is determined by the person's lipid profile and level of cardiovascular risk. The classification of cardiovascular risk and lipid targets for drug treatment differ between the USA and the UK, and the rest of Europe. We used the United Kingdom Prospective Diabetes Study (UKPDS) risk calculator to estimate 10-year cardiovascular risk, and categorised a 15% or more risk as "higher risk", and 15% or less as "lower risk" according to the UK clinical guidelines. We found no RCTs of a solely lower-risk population, although some studies were excluded because of insufficient data to calculate risk. In clinical practice, most people with diabetes are increasingly considered at high cardiovascular risk, regardless of the presence or absence of other risk factors.
Statins are highly effective at improving cardiovascular outcomes in people with diabetes. Statins reduce cardiovascular mortality in people with type 2 diabetes with and without known CVD, and regardless of baseline total and LDL-C concentrations.Different statins seem to have similar efficacy at reducing LDL-C.
Combining statins with other treatments (such as ezetimibe or a fibrate) seems to reduce LDL-C more than statin treatments alone. Combinations could be useful in people with mixed dyslipidaemia where one drug fails to control all lipid parameters.
Fibrates seem to have a beneficial effect on cardiovascular mortality and morbidity by reducing triglyceride levels. In people with mixed dyslipidaemia, statins may also be required.
Intensive-treatment programmes involving multiple interventions (people seen by a nurse every 4-6 weeks) seem better at reducing cholesterol than usual-care programmes.
Fish oils may reduce triglyceride levels, but also seem to increase LDL-C levels, making them of limited benefit to most diabetic patients.
Nicotinic acid seems effective at increasing HDL-C and may reduce triglycerides. However, in clinical practice, nicotinic acid alone is not the preferred treatment for hypertriglyceridaemia, but may be used in combination with a statin in people with mixed dyslipidaemia, or in those unable to tolerate fibrates. Nicotinic acid seems to increase the incidence of flushing, particularly in female patients.
We don't know whether anion exchange resins or ezetimibe are useful in treating dyslipidaemia in people with diabetes, but they could be used in combination with a statin if the statin alone fails to achieve lipid targets.
PMCID: PMC2907966  PMID: 19450295
14.  Effects of Simvastatin on Cholesterol Metabolism and Alzheimer Disease Biomarkers 
Preclinical and epidemiologic studies suggest a protective effect of statins on Alzheimer disease (AD). Experimental evidence indicates that some statins can cross the blood-brain barrier, alter brain cholesterol metabolism, and may ultimately decrease the production of amyloid-β (Aβ) peptide. Despite these promising leads, clinical trials have yielded inconsistent results regarding the benefits of statin treatment in AD. Seeking to detect a biological signal of statins effect on AD, we conducted a 12-week open-label trial with simvastatin 40 mg/d and then 80 mg/d in 12 patients with AD or amnestic mild cognitive impairment and hypercholesterolemia. We quantified cholesterol precursors and metabolites and AD biomarkers of Aβ and tau in both plasma and cerebrospinal fluid at baseline and after the 12-week treatment period. We found a modest but significant inhibition of brain cholesterol biosynthesis after simvastatin treatment, as indexed by a decrease of cerebrospinal fluid lathosterol and plasma 24S-hydroxycholesterol. Despite this effect, there were no changes in AD biomarkers. Our findings indicate that simvastatin treatment can affect brain cholesterol metabolism within 12 weeks, but did not alter molecular indices of AD pathology during this short-term treatment.
doi:10.1097/WAD.0b013e3181d61fea
PMCID: PMC3694274  PMID: 20473136
Alzheimer disease; simvastatin; cholesterol; biomarker
15.  Statins for the primary prevention of cardiovascular disease 
Background
Reducing high blood cholesterol, a risk factor for cardiovascular disease (CVD) events in people with and without a past history of coronary heart disease (CHD) is an important goal of pharmacotherapy. Statins are the first-choice agents. Previous reviews of the effects of statins have highlighted their benefits in people with coronary artery disease. The case for primary prevention, however, is less clear.
Objectives
To assess the effects, both harms and benefits, of statins in people with no history of CVD.
Search methods
To avoid duplication of effort, we checked reference lists of previous systematic reviews. We searched the Cochrane Central Register of Controlled Trials (Issue 1, 2007), MEDLINE (2001 to March 2007) and EMBASE (2003 to March 2007). There were no language restrictions.
Selection criteria
Randomised controlled trials of statins with minimum duration of one year and follow-up of six months, in adults with no restrictions on their total low density lipoprotein (LDL) or high density lipoprotein (HDL) cholesterol levels, and where 10% or less had a history of CVD, were included.
Data collection and analysis
Two authors independently selected studies for inclusion and extracted data. Outcomes included all cause mortality, fatal and non-fatal CHD, CVD and stroke events, combined endpoints (fatal and non-fatal CHD, CVD and stroke events), change in blood total cholesterol concentration, revascularisation, adverse events, quality of life and costs. Relative risk (RR) was calculated for dichotomous data, and for continuous data pooled weighted mean differences (with 95% confidence intervals) were calculated.
Main results
Fourteen randomised control trials (16 trial arms; 34,272 participants) were included. Eleven trials recruited patients with specific conditions (raised lipids, diabetes, hypertension, microalbuminuria). All-cause mortality was reduced by statins (RR 0.84, 95% CI 0.73 to 0.96) as was combined fatal and non-fatal CVD endpoints (RR 0.70, 95% CI 0.61 to 0.79). Benefits were also seen in the reduction of revascularisation rates (RR 0.66, 95% CI 0.53 to 0.83). Total cholesterol and LDL cholesterol were reduced in all trials but there was evidence of heterogeneity of effects. There was no clear evidence of any significant harm caused by statin prescription or of effects on patient quality of life.
Authors’ conclusions
Reductions in all-cause mortality, major vascular events and revascularisations were found with no excess of cancers or muscle pain among people without evidence of cardiovascular disease treated with statins. Other potential adverse events were not reported and some trials included people with cardiovascular disease. Only limited evidence showed that primary prevention with statins may be cost effective and improve patient quality of life. Caution should be taken in prescribing statins for primary prevention among people at low cardiovascular risk.
doi:10.1002/14651858.CD004816.pub4
PMCID: PMC4164175  PMID: 21249663
Cardiovascular Diseases [blood; *prevention & control]; Cause of Death; Cholesterol, HDL [blood]; Cholesterol, LDL [blood]; Hydroxymethylglutaryl-CoA Reductase Inhibitors [adverse effects; *therapeutic use]; Primary Prevention; Randomized Controlled Trials as Topic; Adult; Humans
16.  STATIN USE AND LOWER-EXTREMITY AMPUTATION RISK IN NON-ELDERLY DIABETIC PATIENTS 
Journal of vascular surgery  2013;58(6):10.1016/j.jvs.2013.06.069.
Objective
To examine the association between use of statin and non-statin cholesterol-lowering medications and risk of nontraumatic major lower-extremity amputations (LEA) and treatment failure (LEA or death).
Design of Study
A retrospective cohort of patients with Type I and Type 2 diabetes mellitus (diabetes) was followed for five years between 2004 and 2008. The follow-up exposure duration was divided into 90-day periods. Use of cholesterol-lowering agents, diabetic medications, hemoglobin A1c, body mass index, and systolic and diastolic blood pressures were observed in each period. Demographic factors were observed at baseline. Major risk factors of LEA including peripheral neuropathy, PAD, and foot ulcers were observed at baseline and were updated for each period. LEA and deaths were assessed in each period and their hazard ratios were estimated.
Setting
US Department of Veterans Affairs Healthcare system (VA)
Subjects
Cholesterol drug-naïve patients with Type I or II diabetes who were treated in the VA in 2003 and were <65 years old at the end of follow-up.
Results
Of 83,593 patients in the study cohort, 217 (0.3%) patients experienced a major LEA and 11,716 (14.0%) patients experienced an LEA or death (treatment failure) after a mean follow-up of 4.6 years. Compared to patients who did not use cholesterol-lowering agents, statin users were 35% - 43% less likely to experience an LEA (HR = 0.65; 95% CI, 0.42–0.99) and a treatment failure (HR = 0.57; 95% CI, 0.54–0.60). Users of other cholesterol-lowering medications were not significantly different in LEA risk (HR = 0.95; 95% CI, 0.35–2.60) but had a 41% lower risk of treatment failure (HR = 0.59; 95% CI, 0.51–0.68).
Conclusions
This is the first study to report a significant association between statin use and diminished amputation risk among patients with diabetes. In this non-randomized cohort, beneficial effects of statin therapy were similar to that seen in large-scale clinical trial experience. For LEA risk, those given non-statins did not have a statistically significant benefit and its effect on LEA risk was much smaller compared to statins.. Unanswered questions to be explored in future studies include a comparison of statins of moderate versus high potency in those with high risk of coronary heart disease and an exploration of whether the effects seen in this study are simply effects of cholesterol-lowering or possibly pleiotropic effects.
doi:10.1016/j.jvs.2013.06.069
PMCID: PMC3844128  PMID: 23932803
cholesterol therapy; diabetes; statins; lower-extremity amputation; amputation-free survival
17.  Pitavastatin in cardiometabolic disease: therapeutic profile 
Cardiovascular Diabetology  2013;12(Suppl 1):S2.
Statins effectively lower low-density lipoprotein-cholesterol (LDL-C) and reduce cardiovascular risk in people with dyslipidemia and cardiometabolic diseases such as Metabolic syndrome (MetS) or type 2 diabetes (T2D). In addition to elevated levels of LDL-C, people with these conditions often have other lipid-related risk factors, such as high levels of triglycerides, low levels of high-density lipoprotein-cholesterol (HDL-C), and a preponderance of highly atherogenic, small, dense low-density lipoprotein particles. The optimal management of dyslipidemia in people with MetS or T2D should therefore address each of these risk factors in addition to LDL-C. Although statins typically have similar effects on LDL-C levels, differences in chemical structure and pharmacokinetic profile can lead to variations in pleiotropic effects, adverse event profiles and drug-drug interactions. The choice of statin should therefore depend on the characteristics and needs of the individual patient. Compared with other statins, pitavastatin has distinct pharmacological features that translate into a broad range of actions on both apolipoprotein-B-containing and apolipoprotein-A-containing lipoproteins. Studies show that pitavastatin 1 to 4 mg is well tolerated and significantly improves LDL-C and triglyceride levels to a similar or greater degree than comparable doses of atorvastatin, simvastatin or pravastatin, irrespective of diabetic status. Moreover, whereas most statins show inconsistent effects on HDL-C levels, pitavastatin-treated patients routinely experience clinically significant elevations in HDL-C that are maintained and even increased over the long term. In addition to increasing high-density lipoprotein quantity, pitavastatin appears to improve high-density lipoprotein function and to slow the progression of atherosclerotic plaques by modifying high-density lipoprotein-related inflammation and oxidation, both of which are common in patients with MetS and T2D. When choosing a statin, it is important to note that patients with MetS have an increased risk of developing T2D and that some statins can exacerbate this risk via adverse effects on glucose regulation. Unlike many statins, pitavastatin appears to have a neutral and even beneficial effect on glucose regulation, making it a useful treatment option in this high-risk group of patients. Together with pitavastatin’s beneficial effects on the cardiometabolic lipid profile and its low potential for drug-drug interactions, this suggests that pitavastatin might be a useful lipid-lowering option for people with cardiometabolic disease.
doi:10.1186/1475-2840-12-S1-S2
PMCID: PMC3668168  PMID: 23819752
18.  Atherosclerosis, cholesterol, nutrition, and statins – a critical review 
Atherosclerosis, which causes approximately half of all deaths of adults over age 60 in industrialized nations, is a pandemic among inappropriately nourished and/or physically hypoactive children, adolescents, and adults world wide. Although nowadays statins are widely prescribed to middle age and elderly adults with high blood lipid levels as pharmacological prevention for the late complications of atherosclerosis, from a critical point of view statins seem not to solve the problem, especially when compared with certain natural ingredients of our nutrition like micronutrients as alternative strategy. Statin ingestion is associated with lowering of serum cholesterol and low-density lipoprotein concentrations; some prospective studies have shown statistical associations with subsequent modest reduction of mortality from cardiovascular disease. However, specific biochemical pathways and pharmacological roles of statins in prevention of atherosclerosis, if any, are unknown. Moreover, there have been no systematic cost-benefit analyses of life-style prophylaxis versus statin prophylaxis versus combined life-style plus statin prophylaxis versus neither life-style nor statin prophylaxis for clinically significant complications of cardiovascular diseases in the elderly. Further, in the trials of effectiveness statins were not compared with management of nutrition, which is the most appropriate alternative intervention. Such studies seem to be important, as the ever increasing world population, especially in developing countries, now demand expensive statins, which may be unaffordable for mitigating the pandemic. Studies of this kind are necessary to identify more precisely those patients for whom cardiovascular benefits will outweigh the risks and costs of the statin treatment in comparison with nutritional interventions.
Against the background of the current pathogenetic concept of atherogenesis some of its possible risk factors, particularly the roles of cholesterol and homocysteine, and the effects of statins versus nutritional (micronutrients) interventions in prevention and treatment of the disease are discussed. The prevailing opinion that serum cholesterol as a mediator of the disease is increased by eating saturated fats and decreased by eating polyunsaturated fats is being challenged. Evidently, the beneficial effects of statins in atherosclerosis are not mainly due to its cholesterol lowering effect, rather than to its “pleiotropic effects”. Other pathogenetic factors in atherosclerosis are involved, like inflammatory and immunologic processes, that can be modulated by statins as well as by other drugs or by the Mediterranean-style nutrition and by micronutrients (folate, B-vitamins).
PMCID: PMC2703237  PMID: 19675712
atherosclerosis; nutrition; micronutrients; statins; homocysteine; lipid-hypothesis; cholesterol; Mediterranean-style nutrition; B-vitamins; folate; Atorvastatin; Simvastatin
19.  Interventions for Heart Disease and Their Effects on Alzheimer’s disease 
Neurological research  2006;28(6):630-636.
Objectives
To review the contributions of cardiovascular disease to Alzheimer’s disease and Vascular Dementia.
Methods
Review of the literature
Results
Alzheimer’s disease and Vascular Dementia both share significant risk attributable to cardiovascular risk factors. Hypertension and hypercholesterolemia at midlife are significant risk factors for both subsequent dementia. Diabetes and obesity are also risk factors for dementia. Stressful medical procedures, such as coronary artery bypass and graft operations also appear to contribute to the risk of Alzheimer’s disease. Apolipoprotein E is the major risk factor for Alzheimer’s disease. Apolipoprotein E does not appear to contribute to Alzheimer’s disease by increasing serum cholesterol, but it might contribute to the disease through a mechanism involving both Aβ and an increase in neuronal vulnerability to stress.
Discussion
The strong association of cardiovascular risk factors with Alzheimer’s disease and Vascular dementia suggest that these diseases share some biological pathways in common. The contribution of cardiovascular disease to Alzheimer’s disease and Vascular Dementia suggest that cardiovascular therapies might prove useful in treating or preventing dementia. Anti-hypertensive medications appear to be beneficial in preventing vascular dementia. Statins might be beneficial in preventing the progression of dementia in subjects with Alzheimer’s disease.
doi:10.1179/016164106X130515
PMCID: PMC3913064  PMID: 16945215
beta-amyloid; cholesterol; diabetes; hypertension; statins
20.  Industry sponsorship bias in research findings: a network meta-analysis of LDL cholesterol reduction in randomised trials of statins 
Objective To explore the risk of industry sponsorship bias in a systematically identified set of placebo controlled and active comparator trials of statins.
Design Systematic review and network meta-analysis.
Eligibility Open label and double blind randomised controlled trials comparing one statin with another at any dose or with control (placebo, diet, or usual care) for adults with, or at risk of developing, cardiovascular disease. Only trials that lasted longer than four weeks with more than 50 participants per trial arm were included. Two investigators assessed study eligibility.
Data sources Bibliographic databases and reference lists of relevant articles published between 1 January 1985 and 10 March 2013.
Data extraction One investigator extracted data and another confirmed accuracy.
Main outcome measure Mean absolute change from baseline concentration of low density lipoprotein (LDL) cholesterol.
Data synthesis Study level outcomes from randomised trials were combined using random effects network meta-analyses.
Results We included 183 randomised controlled trials of statins, 103 of which were two-armed or multi-armed active comparator trials. When all of the existing randomised evidence was synthesised in network meta-analyses, there were clear differences in the LDL cholesterol lowering effects of individual statins at different doses. In general, higher doses resulted in higher reductions in baseline LDL cholesterol levels. Of a total of 146 industry sponsored trials, 64 were placebo controlled (43.8%). The corresponding number for the non-industry sponsored trials was 16 (43.2%). Of the 35 unique comparisons available in 37 non-industry sponsored trials, 31 were also available in industry sponsored trials. There were no systematic differences in magnitude between the LDL cholesterol lowering effects of individual statins observed in industry sponsored versus non-industry sponsored trials. In industry sponsored trials, the mean change from baseline LDL cholesterol level was on average 1.77 mg/dL (95% credible interval −11.12 to 7.66) lower than the change observed in non-industry sponsored trials. There was no detectable inconsistency in the evidence network.
Conclusions Our analysis shows that the findings obtained from industry sponsored statin trials seem similar in magnitude as those in non-industry sources. There are actual differences in the effectiveness of individual statins at various doses that explain previously observed discrepancies between industry and non-industry sponsored trials.
doi:10.1136/bmj.g5741
PMCID: PMC4184241  PMID: 25281681
21.  Modulation of Statin-Activated Shedding of Alzheimer APP Ectodomain by ROCK 
PLoS Medicine  2005;2(1):e18.
Background
Statins are widely used cholesterol-lowering drugs that act by inhibiting HMGCoA reductase, the rate-limiting enzyme in cholesterol biosynthesis. Recent evidence suggests that statin use may be associated with a decreased risk for Alzheimer disease, although the mechanisms underlying this apparent risk reduction are poorly understood. One popular hypothesis for statin action is related to the drugs' ability to activate α-secretase-type shedding of the α-secretase-cleaved soluble Alzheimer amyloid precursor protein ectodomain (sAPPα). Statins also inhibit the isoprenoid pathway, thereby modulating the activities of the Rho family of small GTPases—Rho A, B, and C—as well as the activities of Rac and cdc42. Rho proteins, in turn, exert many of their effects via Rho-associated protein kinases (ROCKs). Several cell-surface molecules are substrates for activated α-secretase-type ectodomain shedding, and regulation of shedding typically occurs via activation of protein kinase C or extracellular-signal-regulated protein kinases, or via inactivation of protein phosphatase 1 or 2A. However, the possibility that these enzymes play a role in statin-stimulated shedding has been excluded, leading us to investigate whether the Rho/ROCK1 protein phosphorylation pathway might be involved.
Methods and Findings
We found that both atorvastatin and simvastatin stimulated sAPPα shedding from a neuroblastoma cell line via a subcellular mechanism apparently located upstream of endocytosis. A farnesyl transferase inhibitor also increased sAPPα shedding, as did a dominant negative form of ROCK1. Most conclusively, a constitutively active ROCK1 molecule inhibited statin-stimulated sAPPα shedding.
Conclusion
Together, these data suggest that statins exert their effects on shedding of sAPPα from cultured cells, at least in part, by modulation of the isoprenoid pathway and ROCK1.
The cholesterol-lowering statins seem to have a protective effect against Alzheimer disease. In cultured cells, statins affect cleavage of the amyloid precursor protein via the ROCK kinase. This could explain some of their beneficial effects
doi:10.1371/journal.pmed.0020018
PMCID: PMC543463  PMID: 15647781
22.  Statins and Pulmonary Fibrosis 
Rationale: The role of 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins) in the development or progression of interstitial lung disease (ILD) is controversial.
Objectives: To evaluate the association between statin use and ILD.
Methods: We used regression analyses to evaluate the association between statin use and interstitial lung abnormalities (ILA) in a large cohort of smokers from COPDGene. Next, we evaluated the effect of statin pretreatment on bleomycin-induced fibrosis in mice and explored the mechanism behind these observations in vitro.
Measurements and Main Results: In COPDGene, 38% of subjects with ILA were taking statins compared with 27% of subjects without ILA. Statin use was positively associated in ILA (odds ratio, 1.60; 95% confidence interval, 1.03–2.50; P = 0.04) after adjustment for covariates including a history of high cholesterol or coronary artery disease. This association was modified by the hydrophilicity of statin and the age of the subject. Next, we demonstrate that statin administration aggravates lung injury and fibrosis in bleomycin-treated mice. Statin pretreatment enhances caspase-1–mediated immune responses in vivo and in vitro; the latter responses were abolished in bone marrow–derived macrophages isolated from Nlrp3−/− and Casp1−/− mice. Finally, we provide further insights by demonstrating that statins enhance NLRP3-inflammasome activation by increasing mitochondrial reactive oxygen species generation in macrophages.
Conclusions: Statin use is associated with ILA among smokers in the COPDGene study and enhances bleomycin-induced lung inflammation and fibrosis in the mouse through a mechanism involving enhanced NLRP3-inflammasome activation. Our findings suggest that statins may influence the susceptibility to, or progression of, ILD.
Clinical trial registered with www.clinicaltrials.gov (NCT 00608764).
doi:10.1164/rccm.201108-1574OC
PMCID: PMC3297101  PMID: 22246178
statins; interstitial lung disease; pulmonary fibrosis; inflammasome; mitochondrial reactive oxygen species
23.  Factors Associated with Findings of Published Trials of Drug–Drug Comparisons: Why Some Statins Appear More Efficacious than Others 
PLoS Medicine  2007;4(6):e184.
Background
Published pharmaceutical industry–sponsored trials are more likely than non-industry-sponsored trials to report results and conclusions that favor drug over placebo. Little is known about potential biases in drug–drug comparisons. This study examined associations between research funding source, study design characteristics aimed at reducing bias, and other factors that potentially influence results and conclusions in randomized controlled trials (RCTs) of statin–drug comparisons.
Methods and Findings
This is a cross-sectional study of 192 published RCTs comparing a statin drug to another statin drug or non-statin drug. Data on concealment of allocation, selection bias, blinding, sample size, disclosed funding source, financial ties of authors, results for primary outcomes, and author conclusions were extracted by two coders (weighted kappa 0.80 to 0.97). Univariate and multivariate logistic regression identified associations between independent variables and favorable results and conclusions. Of the RCTs, 50% (95/192) were funded by industry, and 37% (70/192) did not disclose any funding source. Looking at the totality of available evidence, we found that almost all studies (98%, 189/192) used only surrogate outcome measures. Moreover, study design weaknesses common to published statin–drug comparisons included inadequate blinding, lack of concealment of allocation, poor follow-up, and lack of intention-to-treat analyses. In multivariate analysis of the full sample, trials with adequate blinding were less likely to report results favoring the test drug, and sample size was associated with favorable conclusions when controlling for other factors. In multivariate analysis of industry-funded RCTs, funding from the test drug company was associated with results (odds ratio = 20.16 [95% confidence interval 4.37–92.98], p < 0.001) and conclusions (odds ratio = 34.55 [95% confidence interval 7.09–168.4], p < 0.001) that favor the test drug when controlling for other factors. Studies with adequate blinding were less likely to report statistically significant results favoring the test drug.
Conclusions
RCTs of head-to-head comparisons of statins with other drugs are more likely to report results and conclusions favoring the sponsor's product compared to the comparator drug. This bias in drug–drug comparison trials should be considered when making decisions regarding drug choice.
Lisa Bero and colleagues found published trials comparing one statin with another were more likely to report results and conclusions favoring the sponsor's product than the comparison drug.
Editors' Summary
Background.
Randomized controlled trials are generally considered to be the most reliable type of experimental study for evaluating the effectiveness of different treatments. Randomization involves the assignment of participants in the trial to different treatment groups by the play of chance. Properly done, this procedure means that the different groups are comparable at outset, reducing the chance that outside factors could be responsible for treatment effects seen in the trial. When done properly, randomization also ensures that the clinicians recruiting participants into the trial cannot know the treatment group to which a patient will end up being assigned. However, despite these advantages, a large number of factors can still result in bias creeping in. Bias comes about when the findings of research appear to differ in some systematic way from the true result. Other research studies have suggested that funding is a source of bias; studies sponsored by drug companies seem to more often favor the sponsor's drug than trials not sponsored by drug companies
Why Was This Study Done?
The researchers wanted to more precisely understand the impact of different possible sources of bias in the findings of randomized controlled trials. In particular, they wanted to study the outcomes of “head-to-head” drug comparison studies for one particular class of drugs, the statins. Drugs in this class are commonly prescribed to reduce the levels of cholesterol in blood amongst people who are at risk of heart and other types of disease. This drug class is a good example for studying the role of bias in drug–drug comparison trials, because these trials are extensively used in decision making by health-policy makers.
What Did the Researchers Do and Find?
This research study was based on searching PubMed, a biomedical literature database, with the aim of finding all randomized controlled trials of statins carried out between January 1999 and May 2005 (reference lists also were searched). Only trials which compared one statin to another statin or one statin to another type of drug were included. The researchers extracted the following information from each article: the study's source of funding, aspects of study design, the overall results, and the authors' conclusions. The results were categorized to show whether the findings were favorable to the test drug (the newer statin), inconclusive, or not favorable to the test drug. Aspects of each study's design were also categorized in relation to various features, such as how well the randomization was done (in particular, the degree to which the processes used would have prevented physicians from knowing which treatment a patient was likely to receive on enrollment); whether all participants enrolled in the trial were eventually analyzed; and whether investigators or participants knew what treatment an individual was receiving.
One hundred and ninety-two trials were included in this study, and of these, 95 declared drug company funding; 23 declared government or other nonprofit funding while 74 did not declare funding or were not funded. Trials that were properly blinded (where participants and investigators did not know what treatment an individual received) were less likely to have conclusions favoring the test drug. However, large trials were more likely to favor the test drug than smaller trials. When looking specifically at the trials funded by drug companies, the researchers found various factors that predicted whether a result or conclusion favored the test drug. These included the impact of the journal publishing the results; the size of the trial; and whether funding came from the maker of the test drug. However, properly blinded trials were less likely to produce results favoring the test drug. Even once all other factors were accounted for, the funding source for the study was still linked with results and conclusions that favored the maker of the test drug.
What Do These Findings Mean?
This study shows that the type of sponsorship available for randomized controlled trials of statins was strongly linked to the results and conclusions of those studies, even when other factors were taken into account. However, it is not clear from this study why sponsorship has such a strong link to the overall findings. There are many possible reasons why this might be. Some people have suggested that drug companies may deliberately choose lower dosages for the comparison drug when they carry out “head-to-head” trials; this tactic is likely to result in the company's product doing better in the trial. Others have suggested that trials which produce unfavorable results are not published, or that unfavorable outcomes are suppressed. Whatever the reasons for these findings, the implications are important, and suggest that the evidence base relating to statins may be substantially biased.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0040184.
The James Lind Library has been created to help people understand fair tests of treatments in health care by illustrating how fair tests have developed over the centuries
The International Committee of Medical Journal Editors has provided guidance regarding sponsorship, authorship, and accountability
The CONSORT statement is a research tool that provides an evidence-based approach for reporting the results of randomized controlled trials
Good Publication Practice guidelines provide standards for responsible publication of research sponsored by pharmaceutical companies
Information from Wikipedia on Statins. Wikipedia is an internet encyclopedia anyone can edit
doi:10.1371/journal.pmed.0040184
PMCID: PMC1885451  PMID: 17550302
24.  Efficacy, safety and tolerability of ongoing statin plus ezetimibe versus doubling the ongoing statin dose in hypercholesterolemic Taiwanese patients: an open-label, randomized clinical trial 
BMC Research Notes  2012;5:251.
Background
Reducing low-density lipoprotein cholesterol (LDL-C) is associated with reduced risk for major coronary events. Despite statin efficacy, a considerable proportion of statin-treated hypercholesterolemic patients fail to reach therapeutic LDL-C targets as defined by guidelines. This study compared the efficacy of ezetimibe added to ongoing statins with doubling the dose of ongoing statin in a population of Taiwanese patients with hypercholesterolemia.
Methods
This was a randomized, open-label, parallel-group comparison study of ezetimibe 10 mg added to ongoing statin compared with doubling the dose of ongoing statin. Adult Taiwanese hypercholesterolemic patients not at optimal LDL-C levels with previous statin treatment were randomized (N = 83) to ongoing statin + ezetimibe (simvastatin, atorvastatin or pravastatin + ezetimibe at doses of 20/10, 10/10 or 20/10 mg) or doubling the dose of ongoing statin (simvastatin 40 mg, atorvastatin 20 mg or pravastatin 40 mg) for 8 weeks. Percent change in total cholesterol, LDL-C, high-density lipoprotein cholesterol (HDL-C) and triglycerides, and specified safety parameters were assessed at 4 and 8 weeks.
Results
At 8 weeks, patients treated with statin + ezetimibe experienced significantly greater reductions compared with doubling the statin dose in LDL-C (26.2% vs 17.9%, p = 0.0026) and total cholesterol (20.8% vs 12.2%, p = 0.0003). Percentage of patients achieving treatment goal was greater for statin + ezetimibe (58.6%) vs doubling statin (41.2%), but the difference was not statistically significant (p = 0.1675). The safety and tolerability profiles were similar between treatments.
Conclusion
Ezetimibe added to ongoing statin therapy resulted in significantly greater lipid-lowering compared with doubling the dose of statin in Taiwanese patients with hypercholesterolemia. Studies to assess clinical outcome benefit are ongoing.
Trial registration
Registered at ClinicalTrials.gov: NCT00652327
doi:10.1186/1756-0500-5-251
PMCID: PMC3403927  PMID: 22621316
Ezetimibe; Simvastatin; Atorvastatin; Pravastatin
25.  Anti-Angiogenic and Anti-Inflammatory Effects of Statins: Relevance to Anti-Cancer Therapy 
Current cancer drug targets  2005;5(8):579-594.
Angiogenesis is indispensable for the growth of solid tumors and angiogenic factors are also involved in the progression of hematological malignancies. Targeting the formation of blood vessels is therefore regarded as a promising strategy in cancer therapy. Interestingly, besides demonstration of some beneficial effects of novel anti-angiogenic compounds, recent data on the activity of already available drugs point to their potential application in anti-angiogenic therapy. Among these are the statins, the inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A reductase. Statins are very efficient in the treatment of hypercholesterolemia in cardiovascular disorders; however, their effects are pleiotropic and some are not directly related to the inhibition of cholesterol synthesis. Some reports particularly highlight the pro-angiogenic effects of statins, which are caused by low, nanomolar concentrations and are regarded as beneficial for the treatment of cardiovascular diseases. On the other hand, the anti-angiogenic activities, observed at micromolar concentrations of statins, may be of special significance for cancer therapy. Those effects are caused by the inhibition of both proliferation and migration and induction of apoptosis in endothelial cells. Moreover, the statin-mediated inhibition of vascular endothelial growth factor synthesis, the major angiogenic mediator, may contribute to the attenuation of angiogenesis.
It has been suggested that the anti-cancer effect of statins can be potentially exploited for the cancer therapy. However, several clinical trials aimed at the inhibition of tumor growth by treatment with very high doses of statins did not provide conclusive data. Herein, the reasons for those outcomes are discussed and the rationale for further studies is presented.
PMCID: PMC1391922  PMID: 16375664
Vascular endothelial growth factor; 3-hydroxy-3-methylglutaryl-coenzyme A reductase; nitric oxide; heme oxygenase; apoptosis; endothelium; atherosclerosis; hypercholesterolemia; bFGF = Basic fibroblast growth factor; EGF = Epidermal growth factor; eNOS = Endothelial nitric oxide synthase; EPCs = Endothelial progenitor cells; FPP = Farnesylpyrophosphate; GGPP = Geranylgeranyl pyrophosphate; HGM-CoA reductase = 3-hydroxy-3-methylglutaryl-coenzyme A reductase; HMEC-1 = Human microvascular endothelial cells-1; HUVEC = Human umbilical vein endothelial cells; HO-1 = Heme oxygenase-1; IL-8 = Interleukin 8; LPC = Lysophosphatidylcholine; MAPK = Mitogen activated protein kinase; MCP-1 = Monocyte chemotactic protein-1; MMPs = Metalloproteinases; oxLDL = Oxidized low density lipoprotein; PDGF-BB = Platelet-derived growth factor-BB; PI 3-K = Phosphatidylinositol -3-kinase; TGF = Transforming growth factor; TNF = Tumor necrosis factor; UPA = Urokinase plasminogen activator; VEGF = Vascular endothelial growth factor

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