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1.  Autosomal-dominant Alzheimer's disease: a review and proposal for the prevention of Alzheimer's disease 
Autosomal-dominant Alzheimer's disease has provided significant understanding of the pathophysiology of Alzheimer's disease. The present review summarizes clinical, pathological, imaging, biochemical, and molecular studies of autosomal-dominant Alzheimer's disease, highlighting the similarities and differences between the dominantly inherited form of Alzheimer's disease and the more common sporadic form of Alzheimer's disease. Current developments in autosomal-dominant Alzheimer's disease are presented, including the international Dominantly Inherited Alzheimer Network and this network's initiative for clinical trials. Clinical trials in autosomal-dominant Alzheimer's disease may test the amyloid hypothesis, determine the timing of treatment, and lead the way to Alzheimer's disease prevention.
PMCID: PMC3109410  PMID: 21211070
2.  United States Private-Sector Physicians and Pharmaceutical Contract Research: A Qualitative Study 
PLoS Medicine  2012;9(7):e1001271.
Jill Fisher and Corey Kalbaugh describe their findings from a qualitative research study evaluating the motivations of private-sector physicians conducting contract research for the pharmaceutical industry.
There have been dramatic increases over the past 20 years in the number of nonacademic, private-sector physicians who serve as principal investigators on US clinical trials sponsored by the pharmaceutical industry. However, there has been little research on the implications of these investigators' role in clinical investigation. Our objective was to study private-sector clinics involved in US pharmaceutical clinical trials to understand the contract research arrangements supporting drug development, and specifically how private-sector physicians engaged in contract research describe their professional identities.
Methods and Findings
We conducted a qualitative study in 2003–2004 combining observation at 25 private-sector research organizations in the southwestern United States and 63 semi-structured interviews with physicians, research staff, and research participants at those clinics. We used grounded theory to analyze and interpret our data. The 11 private-sector physicians who participated in our study reported becoming principal investigators on industry clinical trials primarily because contract research provides an additional revenue stream. The physicians reported that they saw themselves as trial practitioners and as businesspeople rather than as scientists or researchers.
Our findings suggest that in addition to having financial motivation to participate in contract research, these US private-sector physicians have a professional identity aligned with an industry-based approach to research ethics. The generalizability of these findings and whether they have changed in the intervening years should be addressed in future studies.
Please see later in the article for the Editors' Summary.
Editors' Summary
Before a new drug can be used routinely by physicians, it must be investigated in clinical trials—studies that test the drug's safety and effectiveness in people. In the past, clinical trials were usually undertaken in academic medical centers (institutes where physicians provide clinical care, do research, and teach), but increasingly, clinical trials are being conducted in the private sector as part of a growing contract research system. In the US, for example, most clinical trials completed in the 1980s took place in academic medical centers, but nowadays, more than 70% of trials are conducted by nonacademic (community) physicians working under contract to pharmaceutical companies. The number of private-sector nonacademic physicians serving as principal investigators (PIs) for US clinical trials (the PI takes direct responsibility for completion of the trial) increased from 4,000 in 1990 to 20,250 in 2010, and research contracts for clinical trials are now worth more than USṩ11 billion annually.
Why Was This Study Done?
To date, there has been little research on the implications of this change in the conduct of clinical trials. Academic PIs are often involved in both laboratory and clinical research and are therefore likely to identify closely with the science of trials. By contrast, nonacademic PIs may see clinical trials more as a business opportunity—pharmaceutical contract research is profitable to US physicians because they get paid for every step of the trial process. As a result, pharmaceutical companies may now have more control over clinical trial data and more opportunities to suppress negative data through selective publication of study results than previously. In this qualitative study, the researchers explore the outsourcing of clinical trials to private-sector research clinics through observations of, and in-depth interviews with, physicians and other research staff involved in the US clinical trials industry. A qualitative study collects non-quantitative data such as how physicians feel about doing contract research and about their responsibilities to their patients.
What Did the Researchers Do and Find?
Between October 2003 and September 2004, the researchers observed the interactions between PIs, trial coordinators (individuals who undertake many of the trial activities such as blood collection), and trial participants at 25 US research organizations in the southwestern US and interviewed 63 informants (including 12 PIs) about the trials they were involved in and their reasons for becoming involved. The researchers found that private-sector physicians became PIs on industry-sponsored clinical trials primarily because contract research was financially lucrative. The physicians perceived their roles in terms of business rather than science and claimed that they offered something to the pharmaceutical industry that academics do not—the ability to carry out a diverse range of trials quickly and effectively, regardless of their medical specialty. Finally, the physicians saw their primary ethical responsibility as providing accurate data to the companies that hired them and did not explicitly refer to their ethical responsibility to trial participants. One possible reason for this shift in ethical concerns is the belief among private-sector physicians that pharmaceutical companies must be making scientifically and ethically sound decisions when designing trials because of the amount of money they invest in them.
What Do These Findings Mean?
These findings suggest that private-sector physicians participate as PIs in pharmaceutical clinical trials primarily for financial reasons and see themselves as trial practitioners and businesspeople rather than as scientists. The accuracy of these findings is likely to be limited by the small number of PIs interviewed and by the time that has elapsed since the researchers collected their qualitative data. Moreover, these findings may not be generalizable to other regions of the US or to other countries. Nevertheless, they have potentially troubling implications for drug development. By hiring private-sector physicians who see themselves as involved more with the business than the science of contract research, pharmaceutical companies may be able to exert more control over the conduct of clinical trials and the publication of trial results than previously. Compared to the traditional investigatorinitiated system of clinical research, this new system of contract research means that clinical trials now lack the independence that is at the heart of best science practices, a development that casts doubt on the robustness of the knowledge being produced about the safety and effectiveness of new drugs.
Additional Information
Please access these websites via the online version of this summary at
The website is a searchable register of federally and privately supported clinical trials in the US; it provides information about all aspects of clinical trials
The US National Institutes of Health provides information about clinical trials, including personal stories about clinical trials from patients and researchers
The UK National Health Service Choices website has information for patients about clinical trials and medical research, including personal stories about participating in clinical trials
The UK Medical Research Council Clinical Trials Unit also provides information for patients about clinical trials and links to information on clinical trials provided by other organizations
MedlinePlus has links to further resources on clinical trials (in English and Spanish)
PMCID: PMC3404112  PMID: 22911055
3.  The Impact of the Availability of Prevention Studies on the Desire to Undergo Predictive Testing in Persons at-risk for Autosomal Dominant Alzheimer’s Disease 
Contemporary clinical trials  2013;36(1):10.1016/j.cct.2013.07.006.
Persons at-risk for autosomal dominant neurodegenerative diseases provide the opportunity to efficiently test preventive interventions. Only a minority of such persons, however, choose to undergo revealing genetic testing, presenting a challenge to enrollment. Thirty-four preclinical Latinos (n = 26) and non-Latinos at-risk for familial Alzheimer’s disease (FAD) unaware of their genetic status were administered a questionnaire exploring their interest in undergoing revealing genetic testing at baseline and in the context of eligibility for four prevention trials of increasing invasiveness. Forty-four percent of subjects expressed a baseline interest in undergoing revealing testing which increased to 85% in order to be eligible for a study of an oral drug "felt to be very safe.” If there were a 50% chance of receiving placebo, this number dropped to 62% (p = 0.02). For those not interested in a study involving a 50% chance of receiving placebo, a range of 5% to 40% chance of receiving placebo was given as acceptable. For more invasive studies, living in the U.S. (as opposed to Mexico) positively influenced the likelihood of participating. Our data suggests that clinical trial designs in which persons must confront their genetic status prior to enrollment are feasible. Study designs to minimize the likelihood of being placed on placebo or provide the eventual administration of the drug through open-label extensions should be considered.
PMCID: PMC3858206  PMID: 23876673
FAD; pre-symptomatic; genetic; testing; trials; prevention
4.  Tolvaptan in Patients with Autosomal Dominant Polycystic Kidney Disease 
The New England journal of medicine  2012;367(25):2407-2418.
The course of autosomal dominant polycystic kidney disease (ADPKD) is often associated with pain, hypertension, and kidney failure. Preclinical studies indicated that vasopressin V2-receptor antagonists inhibit cyst growth and slow the decline of kidney function.
In this phase 3, multicenter, double-blind, placebo-controlled, 3-year trial, we randomly assigned 1445 patients, 18 to 50 years of age, who had ADPKD with a total kidney volume of 750 ml or more and an estimated creatinine clearance of 60 ml per minute or more, in a 2:1 ratio to receive tolvaptan, a V2-receptor antagonist, at the highest of three twice-daily dose regimens that the patient found tolerable, or placebo. The primary outcome was the annual rate of change in the total kidney volume. Sequential secondary end points included a composite of time to clinical progression (defined as worsening kidney function, kidney pain, hypertension, and albuminuria) and rate of kidney-function decline.
Over a 3-year period, the increase in total kidney volume in the tolvaptan group was 2.8% per year (95% confidence interval [CI], 2.5 to 3.1), versus 5.5% per year in the placebo group (95% CI, 5.1 to 6.0; P<0.001). The composite end point favored tolvaptan over placebo (44 vs. 50 events per 100 follow-up-years, P = 0.01), with lower rates of worsening kidney function (2 vs. 5 events per 100 person-years of follow-up, P<0.001) and kidney pain (5 vs. 7 events per 100 person-years of follow-up, P = 0.007). Tolvaptan was associated with a slower decline in kidney function (reciprocal of the serum creatinine level, −2.61 [mg per milliliter]−1 per year vs. −3.81 [mg per milliliter]−1 per year; P<0.001). There were fewer ADPKD-related adverse events in the tolvaptan group but more events related to aquaresis (excretion of electrolyte-free water) and hepatic adverse events unrelated to ADPKD, contributing to a higher discontinuation rate (23%, vs. 14% in the placebo group).
Tolvaptan, as compared with placebo, slowed the increase in total kidney volume and the decline in kidney function over a 3-year period in patients with ADPKD but was associated with a higher discontinuation rate, owing to adverse events. (Funded by Otsuka Pharmaceuticals and Otsuka Pharmaceutical Development and Commercialization; TEMPO 3:4 number, NCT00428948.)
PMCID: PMC3760207  PMID: 23121377
5.  Clinical and Psychological Characteristics of Initial Cohort of the Dominantly Inherited Alzheimer Network (DIAN) 
Neuropsychology  2013;28(1):10.1037/neu0000030.
To describe clinical, cognitive, and personality characteristics at baseline assessment of 249 participants 19 to 60 years of age in a multinational longitudinal study (DIAN) of autosomal dominant Alzheimer disease (ADAD).
Participants (74% cognitively normal) were from ADAD families with mutations in one of three genes (APP, PSEN1, or PSEN2). Mixed model analyses including family as a random variable and controlling for years from expected time of symptomatic onset of ADAD based on parental age at onset compared three groups (cognitively normal mutation noncarriers, cognitively normal mutation carriers, very mildly impaired mutation carriers).
Global cognitive deficits similar to those observed in late-life sporadic Alzheimer disease (AD) existed in very mild ADAD compared with cognitively normal carriers and noncarriers on all but two measures (Digit Span Backward, Letter Fluency for FAS) of episodic memory, semantic memory, working memory, attention, and speeded visuospatial abilities. Demented individuals were less extraverted, open, and conscientious than cognitively normal participants on the International Personality Item Pool. Differences in the relation between three measures (Logical Memory, Digit Symbol, attention switching) and time to expected age at symptomatic onset indicate that cognitive deficits on some measures can be detected in mutation carriers prior to symptomatic AD and hence should be useful markers in subsequent longitudinal follow-up.
Overall cognitive and personality deficits in very mild ADAD are similar to those seen in sporadic AD. Cognitive deficits also occur in asymptomatic mutation carriers who are closer to the expected time of dementia onset.
PMCID: PMC3877741  PMID: 24219606
Alzheimer disease; early onset; preclinical; cognition; personality
6.  The heart in limb girdle muscular dystrophy 
Heart  1998;79(1):73-77.
Objective—To assess the frequency, nature, and severity of cardiac abnormalities in limb girdle muscular dystrophy, and its relation to age and weakness in various genotypes.
Design—In 26 autosomal dominant, 38 autosomal recessive, and 33 sporadic strictly defined patients with limb girdle muscular dystrophy, cardiac evaluation included history, physical examination, chest x ray, electrocardiography, 24 hour ECG Holter monitoring, and echocardiography. In 35 of the 71 autosomal recessive and sporadic cases muscle biopsies were available for sarcoglycan analysis.
Main results—Dilated cardiomyopathy was present in one autosomal dominant case and in three advanced autosomal recessive or sporadic patients, of whom two were found to have α sarcoglycan deficiency. Two of these three patients and three other cases showed ECG abnormalities known to be characteristic of the dystrophinopathies. A strong association between the absence of α sarcoglycan and the presence of dilated cardiomyopathy was found (p = 0.04). In six autosomal dominant cases there were atrioventricular (AV) conduction disturbances, increasing in severity with age and in concomitant presence of muscle weakness. Pacemaker implantation was necessary in four.
Conclusions—10% of these patients had clinically relevant cardiac abnormalities. In autosomal dominant limb girdle muscular dystrophy one subtype characterised by muscle weakness and AV conduction disturbances is recognised. In the course of autosomal recessive/sporadic limb girdle muscular dystrophy, dilated cardiomyopathy may develop, probably related to deficiency of dystrophin associated proteins.

 Keywords: limb girdle muscular dystrophy;  cardiomyopathy;  AV conduction block;  sarcoglycan
PMCID: PMC1728583  PMID: 9505924
7.  Genetic Heterogeneity in Alzheimer Disease and Implications for Treatment Strategies 
Since the original publication describing the illness in 1907, the genetic understanding of Alzheimer’s disease (AD) has advanced such that it is now clear that it is a genetically heterogeneous condition, the subtypes of which may not uniformly respond to a given intervention. It is therefore critical to characterize the clinical and preclinical stages of AD subtypes, including the rare autosomal dominant forms caused by known mutations in the PSEN1, APP, and PSEN2 genes that are being studied in the Dominantly Inherited Alzheimer Network study and its associated secondary prevention trial. Similar efforts are occurring in an extended Colombian family with a PSEN1 mutation, in APOE ε4 homozygotes, and in Down syndrome. Despite commonalities in the mechanisms producing the AD phenotype, there are also differences that reflect specific genetic origins. Treatment modalities should be chosen and trials designed with these differences in mind. Ideally, the varying pathological cascades involved in the different subtypes of AD should be defined so that both areas of overlap and of distinct differences can be taken into account. At the very least, clinical trials should determine the influence of known genetic factors in post hoc analyses.
PMCID: PMC4162987  PMID: 25217249
Alzheimer’s disease; Genetic; Heterogeneity; Presenilin; Amyloid precursor protein; Apolipoprotein E
8.  Cost-Effectiveness of Tolvaptan in Autosomal Dominant Polycystic Kidney Disease 
Annals of internal medicine  2013;159(6):382-389.
In the Tolvaptan Efficacy and Safety in Management of Autosomal Dominant Polycystic Kidney Disease and its Outcomes (TEMPO) trial, tolvaptan significantly reduced expansion of kidney volume and loss of kidney function.
To determine how benefits observed in the TEMPO trial might relate to longer-term health outcomes such as progression to end-stage renal disease (ESRD) and mortality in addition to its cost-effectiveness.
A decision-analytic model.
Data Sources:
Published literature.
Target Population:
Persons with early Autosomal Dominant Polycystic Kidney Disease (ADPKD).
Time Horizon:
We compared a strategy where patients receive tolvaptan therapy until death, development of ESRD, or liver complications to one where they do not receive tolvaptan.
Outcome Measures:
Median age at ESRD onset, life expectancy, discounted quality-adjusted life years (QALYs) and lifetime costs (in 2010 USD), and incremental cost-effectiveness ratios.
Results of Base Case Analysis:
Tolvaptan prolonged the median age at ESRD onset by 6.5 years and increased life expectancy by 2.6 years. At a drug cost of $5,760 per month, tolvaptan cost $744,100 per QALY gained compared to standard care.
Results of Sensitivity Analysis:
For patients with ADPKD progressing more slowly, tolvaptan’s cost per QALY gained was even higher.
Although the TEMPO trial followed patients for 3 years, our main analysis assumed that the clinical benefits of tolvaptan persisted over patients’ lifetimes.
Conclusions and Relevance:
Assuming that tolvaptan’s benefits persist longer term, the drug may slow progression to ESRD and reduce mortality. However, barring an approximately 95% reduction in the price of tolvaptan, its cost-effectiveness does not compare favorably with many other commonly accepted medical interventions.
PMCID: PMC3981098  PMID: 24042366
autosomal dominant polycystic kidney disease; tolvaptan; cost-effectiveness
9.  Congenital hereditary endothelial dystrophy with progressive sensorineural deafness (Harboyan syndrome) 
Harboyan syndrome is a degenerative corneal disorder defined as congenital hereditary endothelial dystrophy (CHED) accompanied by progressive, postlingual sensorineural hearing loss. To date, 24 cases from 11 families of various origin (Asian Indian, South American Indian, Sephardi Jewish, Brazilian Portuguese, Dutch, Gypsy, Moroccan, Dominican) have been reported. More than 50% of the reported cases have been associated with parental consanguinity. The ocular manifestations in Harboyan syndrome include diffuse bilateral corneal edema occurring with severe corneal clouding, blurred vision, visual loss and nystagmus. They are apparent at birth or within the neonatal period and are indistinguishable from those characteristic of the autosomal recessive CHED (CHED2). Hearing deficit in Harboyan is slowly progressive and typically found in patients 10–25 years old. There are no reported cases with prelinglual deafness, however, a significant hearing loss in children as young as 4 years old has been detected by audiometry, suggesting that hearing may be affected earlier, even at birth. Harboyan syndrome is caused by mutations in the SLC4A11 gene located at the CHED2 locus on chromosome 20p13-p12, indicating that CHED2 and Harboyan syndrome are allelic disorders. A total of 62 different SLC4A11 mutations have been reported in 98 families (92 CHED2 and 6 Harboyan). All reported cases have been consistent with autosomal recessive transmission. Diagnosis is based on clinical criteria, detailed ophthalmological assessment and audiometry. A molecular confirmation of the clinical diagnosis is feasible. A variety of genetic, metabolic, developmental and acquired diseases presenting with clouding of the cornea should be considered in the differential diagnosis (Peters anomaly, sclerocornea, limbal dermoids, congenital glaucoma). Audiometry must be performed to differentiate Harboyan syndrome from CHED2. Autosomal recessive types of CHED (CHED2 and Harboyan syndrome) should carefully be distinguished from the less severe autosomal dominant type CHED1. The ocular abnormalities in patients with Harboyan syndrome may be treated with topical hyperosmolar solutions. However, corneal transplantation (penetrating keratoplasty) represents definitive treatment. Corneal transplantation produces a substantial visual gain and has a relatively good surgical prognosis. Audiometric monitoring should be offered to all patients with CHED2. Hearing aids may be necessary in adolescence.
PMCID: PMC2576053  PMID: 18922146
10.  Low-Density Lipoprotein Apheresis 
Executive Summary
To assess the effectiveness and safety of low-density lipoprotein (LDL) apheresis performed with the heparin-induced extracorporeal LDL precipitation (HELP) system for the treatment of patients with refractory homozygous (HMZ) and heterozygous (HTZ) familial hypercholesterolemia (FH).
Background on Familial Hypercholesterolemia
Familial hypercholesterolemia is a genetic autosomal dominant disorder that is caused by several mutations in the LDL-receptor gene. The reduced number or absence of functional LDL receptors results in impaired hepatic clearance of circulating low-density lipoprotein cholesterol (LDL-C) particles, which results in extremely high levels of LDL-C in the bloodstream. Familial hypercholesterolemia is characterized by excess LDL-C deposits in tendons and arterial walls, early onset of atherosclerotic disease, and premature cardiac death.
Familial hypercholesterolemia occurs in both HTZ and HMZ forms.
Heterozygous FH is one of the most common monogenic metabolic disorders in the general population, occurring in approximately 1 in 500 individuals1. Nevertheless, HTZ FH is largely undiagnosed and an accurate diagnosis occurs in only about 15% of affected patients in Canada. Thus, it is estimated that there are approximately 3,800 diagnosed and 21,680 undiagnosed cases of HTZ FH in Ontario.
In HTZ FH patients, half of the LDL receptors do not work properly or are absent, resulting in plasma LDL-C levels 2- to 3-fold higher than normal (range 7-15mmol/L or 300-500mg/dL). Most HTZ FH patients are not diagnosed until middle age when either they or one of their siblings present with symptomatic coronary artery disease (CAD). Without lipid-lowering treatment, 50% of males die before the age of 50 and 25% of females die before the age of 60, from myocardial infarction or sudden death.
In contrast to the HTZ form, HMZ FH is rare (occurring in 1 case per million persons) and more severe, with a 6- to 8-fold elevation in plasma LDL-C levels (range 15-25mmol/L or 500-1000mg/dL). Homozygous FH patients are typically diagnosed in infancy, usually due to the presence of cholesterol deposits in the skin and tendons. The main complication of HMZ FH is supravalvular aortic stenosis, which is caused by cholesterol deposits on the aortic valve and in the ascending aorta. The average life expectancy of affected individuals is 23 to 25 years. In Ontario, it is estimated that there are 13 to 15 cases of HMZ FH. An Ontario clinical expert confirmed that 9 HMZ FH patients have been identified to date.
There are 2 accepted clinical diagnostic criterion for the diagnosis of FH: the Simon Broome FH Register criteria from the United Kingdom and the Dutch Lipid Network criteria from the Netherlands. The criterion supplement cholesterol levels with clinical history, physical signs and family history. DNA-based-mutation-screening methods permit a definitive diagnosis of HTZ FH to be made. However, given that there are over 1000 identified mutations in the LDL receptor gene and that the detection rates of current techniques are low, genetic testing becomes problematic in countries with high genetic heterogeneity, such as Canada.
The primary aim of treatment in both HTZ and HMZ FH is to reduce plasma LDL-C levels in order to reduce the risk of developing atherosclerosis and CAD.
The first line of treatment is dietary intervention, however it alone is rarely sufficient for the treatment of FH patients. Patients are frequently treated with lipid-lowering drugs such as resins, fibrates, niacin, statins and cholesterol absorption-inhibiting drugs (ezetimibe). Most HTZ FH patients require a combination of drugs to achieve or approach target cholesterol levels.
A small number of HTZ FH patients are refractory to treatment or intolerant to lipid-lowering medication. According to clinical experts, the prevalence of refractory HTZ FH in Ontario is between 1 to 5%. Using the mean of 3%, it is estimated that there are approximately 765 refractory HTZ FH patients in Ontario, of which 115 are diagnosed and 650 are undiagnosed.
Drug therapy is less effective in HMZ FH patients since the effects of the majority of cholesterol-lowering drugs are mediated by the upregulation of LDL receptors, which are often absent or function poorly in HMZ FH patients. Some HMZ FH patients may still benefit from drug therapy, however this rarely reduces LDL-C levels to targeted levels.
Existing Technology: Plasma Exchange
An option currently available in Ontario for FH patients who do not respond to standard diet and drug therapy is plasma exchange (PE). Patients are treated with this lifelong therapy on a weekly or biweekly basis with concomitant drug therapy.
Plasma exchange is nonspecific and eliminates virtually all plasma proteins such as albumin, immunoglobulins, coagulation factors, fibrinolytic factors and HDL-C, in addition to acutely lowering LDL-C by about 50%. Blood is removed from the patient, plasma is isolated, discarded and replaced with a substitution fluid. The substitution fluid and the remaining cellular components of the blood are then returned to the patient.
The major limitation of PE is its nonspecificity. The removal of HDL-C prevents successful vascular remodeling of the areas stenosed by atherosclerosis. In addition, there is an increased susceptibility to infections, and costs are incurred by the need for replacement fluid. Adverse events can be expected to occur in 12% of procedures.
Other Alternatives
Surgical alternatives for FH patients include portocaval shunt, ileal bypass and liver transplantation. However, these are risky procedures and are associated with a high morbidity rate. Results with gene therapy are not convincing to date.
The Technology Being Reviewed: LDL Apheresis
An alternative to PE is LDL apheresis. Unlike PE, LDL apheresis is a selective treatment that removes LDL-C and other atherogenic lipoproteins from the blood while minimally impacting other plasma components such as HDL-C, total serum protein, albumin and immunoglobulins. As with PE, FH patients require lifelong therapy with LDL apheresis on a weekly/biweekly basis with concomitant drug therapy.
Heparin-Induced Extracorporeal LDL Precipitation
Heparin-induced extracorporeal LDL precipitation (HELP) is one of the most widely used methods of LDL apheresis. It is a continuous closed-loop system that processes blood extracorporeally. It operates on the principle that at a low pH, LDL and lipoprotein (a) [Lp(a)] bind to heparin and fibrinogen to form a precipitate which is then removed by filtration. In general, the total duration of treatment is approximately 2 to 3 hours.
Results from early trials indicate that LDL-C concentration is reduced by 65% to 70% immediately following treatment in both HMZ and HTZ FH and then rapidly begins to rise. Typically patients with HTZ FH are treated every 2 weeks while patients with HMZ FH require weekly therapy. Heparin-induced extracorporeal LDL precipitation also produces small transient decreases in HDL-C, however levels generally return to baseline within 2 days. After several months of therapy, long-term reductions in LDL-C and increases in HDL-C have been reported.
In addition to having an impact on plasma cholesterol concentrations, HELP lowers plasma fibrinogen, a risk factor for atherosclerosis, and reduces concentrations of cellular adhesion molecules, which play a role in early atherogenesis.
In comparison with PE, HELP LDL apheresis does not have major effects on essential plasma proteins and does not require replacement fluid, thus decreasing susceptibility to infections. One study noted that adverse events were documented in 2.9% of LDL apheresis treatments using the HELP system compared with 12% using PE. As per the manufacturer, patients must weigh at least 30kgs to be eligible for treatment with HELP.
Regulatory Status
The H.E.L.P.® System (B.Braun Medizintechnologie GmbH, Germany) has been licensed by Health Canada since December 2000 as a Class 3 medical device (Licence # 26023) for performing LDL apheresis to acutely remove LDL from the plasma of 3 high-risk patient populations for whom diet has been ineffective and maximum drug therapy has either been ineffective or not tolerated. The 3 patient groups are as follows:
Functional hypercholesterolemic homozygotes with LDL-C >500 mg/dL (>13mmol/L);
Functional hypercholesterolemic heterozygotes with LDL-C >300 mg/dL (>7.8mmol/L);
Functional hypercholesterolemic heterozygotes with LDL-C >200 mg/dL (>5.2mmol/L) and documented CAD
No other LDL apheresis system is currently licensed in Canada.
Review Strategy
The Medical Advisory Secretariat systematically reviewed the literature to assess the effectiveness and safety of LDL apheresis performed with the HELP system for the treatment of patients with refractory HMZ and HTZ FH. A standard search methodology was used to retrieve international health technology assessments and English-language journal articles from selected databases.
The GRADE approach was used to systematically and explicitly make judgments about the quality of evidence and strength of recommendations.
Summary of Findings
The search identified 398 articles published from January 1, 1998 to May 30, 2007. Eight studies met the inclusion criteria. Five case series, 2 case series nested within comparative studies, and one retrospective review, were included in the analysis. A health technology assessment conducted by the Alberta Heritage Foundation for Medical Research, and a review by the United States Food and Drug Administration were also included.
Large heterogeneity among the studies was observed. Studies varied in inclusion criteria, baseline patient characteristics and methodology.
Overall, the mean acute1 relative decrease in LDL-C with HELP LDL apheresis ranged from 53 to 77%. The mean acute relative reductions ranged as follows: total cholesterol (TC) 47 to 64%, HDL-C +0.4 to -29%, triglycerides (TG) 33 to 62%, Lp(a) 55 to 68% and fibrinogen 56 to 65%.
The mean chronic2 relative decreases in LDL-C and TC with HELP LDL apheresis ranged from 9 to 46% and 5 to 34%, respectively. Familial hypercholesterolemia patients treated with HELP did not achieve the target LDL-C value set by international guidelines (LDL-C < 2.5mmol/L, 100mg/dL). The chronic mean relative increase in HDL-C ranged from 12 to 27%. The ratio of LDL:HDL and the ratio of TC:HDL are 2 measures that have been shown to be important risk factors for cardiac events. In high-risk patients, the recommended target LDL:HDL ratio is less than or equal to 2, and the target TC:HDL ratio is less than 4. In the studies that reported chronic lipid changes, the LDL:HDL and TC:HDL ratios exceeded targeted values.
Three studies investigated the effects of HELP on coronary outcomes and atherosclerotic changes. One noted that twice as many lesions displayed regression in comparison to those displaying progression. The second study found that there was a decrease in Agatston scores3 and in the volume of coronary calcium. The last study noted that 2 of 5 patients showed regression of coronary atherosclerosis, and 3 of the 5 patients showed no change as assessed by a global change score.
Adverse effects were typically mild and transient, and the majority of events were related to problems with vascular access. Of the 3 studies that provided quantitative information, the proportion of adverse events ranged from 2.9 to 5.1%.
GRADE Quality of Evidence
In general, studies were of low quality, i.e., case series studies (Tables 1-3). No controlled studies were identified and no studies directly compared the effectiveness of the HELP system with PE or with diet and drug therapy. Conducting trials with a sufficiently large control group would not have been feasible or acceptable given that HELP represents a last alternative in these patients who are resistant to conventional therapeutic strategies.
A major limitation is that there is limited evidence on the effectiveness and safety of HELP apheresis in HMZ FH patients. However, it is unlikely that better-quality evidence will become available, given that HMZ FH is rare and LDL apheresis is a last therapeutic option for these patients.
Lastly, there is limited data on the long-term effects of LDL apheresis in FH patients. No studies with HELP were identified that examined long-term outcomes such as survival and cardiovascular events. The absence of this data may be attributed to the rarity of the condition, and the large number of subjects and long duration of follow-up that would be needed to conduct such trials.
Homozygous Familial Hypercholesterolemia - Lipid Outcomes
Heterozygous Familial Hypercholesterolemia - Lipid Outcomes
Heterozygous Familial Hypercholesterolemia - Coronary Artery Disease Outcomes
Economic Analysis
A budget-impact analysis was conducted to forecast future costs for PE and HELP apheresis in FH patients. All costs are reported in Canadian dollars. Based on epidemiological data of 13 HMZ, 115 diagnosed HTZ and 765 cases of all HTZ patients (diagnosed + undiagnosed), the annual cost of weekly treatment was estimated to be $488,025, $4,332,227 and $24,758,556 respectively for PE. For HELP apheresis, the annual cost of weekly treatment was estimated to be $1,025,338, $9,156,209 and $60,982,579 respectively. Costs for PE and HELP apheresis were halved with a biweekly treatment schedule.
The cost per coronary artery disease death avoided over a 10-year period in HTZ FH-diagnosed patients was also calculated and estimated to be $37.5 million and $18.7 million for weekly and biweekly treatment respectively, when comparing HELP apheresis with PE and with no intervention. Although HELP apheresis costs twice as much as PE, it helped to avoid 12 deaths compared with PE and 22 deaths compared with no intervention, over a period of 10 years.
Ontario Health System Impact Analysis
Low-density lipoprotein apheresis using the HELP system is currently being funded by the provinces of Quebec and Alberta. The program in Quebec has been in operation since 2001 and is limited to the treatment of HMZ FH patients. The Alberta program is relatively new and is currently treating HMZ FH patients, but it is expanding to include refractory HTZ FH patients.
Low-density lipoprotein apheresis is a lifelong treatment and requires considerable commitment on the part of the patient, and the patient’s family and physician. In addition, the management of FH continues to evolve. With the advent of new more powerful cholesterol-lowering drugs, some HTZ patients may be able to sufficiently control their hypercholesterolemia. Nevertheless, according to clinical experts, HMZ patients will likely always require LDL apheresis.
Given the substantial costs associated with LDL apheresis, treatment has been limited to HMZ FH patients. However, LDL apheresis could be applied to a much larger population, which would include HTZ FH patients who are refractory to diet and drug therapy. HTZ FH patients are generally recruited in a more advanced state, demonstrate a longer natural survival than HMZ FH patients and are older.
For HMZ FH patients, the benefits of LDL apheresis clearly outweigh the risks and burdens. According to GRADE, the recommendation would be graded as strong, with low- to very low-quality evidence (Table 4).
In both HMZ and HTZ FH patients, there is evidence of overall clinical benefit of LDL apheresis from case series studies. Low-density lipoprotein apheresis has several advantages over the current treatment of PE, including decreased exposure to blood products, decreased risk of adverse events, conservation of nonatherogenic and athero-protective components, such as HDL-C and lowering of other atherogenic components, such as fibrinogen.
In contrast to HMZ FH patients, there remains a lot of uncertainty in the social/ethical acceptance of this technology for the treatment of refractory HTZ FH patients. In addition to the substantial costs, it is unknown whether the current health care system could cope with the additional demand. There is uncertainty in the estimates of benefits, risks and burdens. According to GRADE, the recommendation would be graded as weak with low- to very-low-quality evidence (Table 5).
GRADE Recommendation - Homozygous Patients
GRADE of recommendation: Strong recommendation, low-quality or very-low-quality evidence
Benefits clearly outweigh risk and burdens
Case series study designs
Strong, but may change when higher-quality evidence becomes available
GRADE Recommendation - Heterozygous Patients
GRADE of recommendation: Weak recommendation, low-quality or very-low-quality evidence
Uncertainty in the estimates of benefits, risks and burden, which these may be closely balanced
Case series study designs
Very weak; other alternatives may be equally reasonable
PMCID: PMC3377562  PMID: 23074505
11.  Commentary on “A roadmap for the prevention of dementia II. Leon Thal Symposium 2008.” Prevention Trials in Persons At-Risk for Dominantly-Inherited Alzheimer's Disease: Opportunities and Challenges 
Autosomal dominant familial Alzheimer's disease (FAD) of young onset due to alterations in the PSEN1, APP, and PSEN2 genes is a fully-penetrant and devastating condition. As the subsequent development of AD in persons inheriting such genes is essentially certain, the condition provides a unique opportunity to perform informative studies of interventions with potential for preventing the disease. Though feasible, there are many challenges to such an endeavor including the fact that most persons at-risk for FAD do not desire to know their genetic status. Other challenges include the time course over which a preventative treatment would need to be administered and potential limitations to the degree to which the knowledge gained might be validly generalized to the more common late-onset AD. In this paper we discuss issues of study design including power estimates, protocols in which subjects' genetic status is not revealed to them, and the advantage of one-time interventions such as vaccinations. Though addressed in the context of FAD, many of the issues discussed are relevant to other fully-penetrant autosomal dominant degenerative illnesses such as Huntington's disease. We also discuss important next steps including the performance of pre-clinical studies in model systems appropriate for FAD and the recently funded international Dominantly Inherited Alzheimer Network (DIAN). The goals of the DIAN are to characterize the natural history of FAD and to establish the infrastructure that would be required to perform meaningful studies in this rare, widely dispersed, but informative population.
PMCID: PMC2746429  PMID: 19328453
12.  On the heredity of retinitis pigmentosa. 
The aims of this study are: (1) to determine the frequencies of the various genetic forms of retinitis pigmentosa; and (2) to perform segregation analysis on autosomal dominant, autosomal recessive, and X-linked families. The families studied consisted of 2 series of patients at Moorfields Eye Hospital: (1) 426 families seen in the Genetic Clinic; and (2) 289 families seen in the Electrodiagnostic Department. Comparison between the 2 series identified biases of ascertainment, and it was estimated that the combined series included 53% of simplex cases and a minimum of 15% of X-linked families. Segregation analysis of the Genetic Clinic series showed good agreement with expectation in autosomal dominant and X-linked families, but indicated that no more than 70% of all simplex cases were autosomal recessive. The rest of the simplex cases were mildly affected and may represent fresh autosomal dominant mutations, autosomal dominant transmission with reduced penetrance, the heterozygous state of X-linked disease in some of the females, and phenocopies.
PMCID: PMC1039814  PMID: 7093178
13.  MYH9 Genetic Variants Associated With Glomerular Disease: What Is the Role for Genetic Testing? 
Seminars in nephrology  2010;30(4):409-417.
Genetic variation in MYH9, encoding nonmuscle myosin IIA heavy chain, has been associated recently with increased risk for kidney disease. Previously, MYH9 missense mutations have been shown to cause the autosomal-dominant MYH9 (ADM9) spectrum, characterized by large platelets, leukocyte Döhle bodies, and, variably, sensorineural deafness, cataracts, and glomerulopathy. Genetic testing is indicated for familial and sporadic cases that fit this spectrum. By contrast, the MYH9 kidney risk variant is characterized by multiple intronic single nucleotide polymorphisms, but the causative variant has not been identified. Disease associations include human immunodeficiency virus-associated collapsing glomerulopathy, focal segmental glomerulosclerosis, hypertension-attributed end-stage kidney disease, and diabetes-attributed end-stage kidney disease. One plausible hypothesis is that the MYH9 kidney risk variant confers a fragile podocyte phenotype. In the case of hypertension-attributed kidney disease, it remains unclear if the hypertension is a contributing cause or a consequence of glomerular injury. The MYH9 kidney risk variant is strikingly more common among individuals of African descent, but only some will develop clinical kidney disease in their lifetime. Thus, it is likely that additional genes and/or environmental factors interact with the MYH9 kidney risk variant to trigger glomerular injury. A preliminary genetic risk stratification scheme, using 10 single nucleotide polymorphisms, may estimate lifetime risk for kidney disease. Nevertheless, at present, no role has been established for genetic testing as part of personalized medicine, but testing should be considered in clinical studies of glomerular diseases among populations of African descent. Such studies will address critical questions pertaining to MYH9-associated kidney disease, including mechanism, course, and response to therapy.
PMCID: PMC3097395  PMID: 20807613
Focal segmental glomerulosclerosis; HIV-associated nephropathy; hypertensive nephrosclerosis; chronic kidney disease; end-stage kidney disease; African American
14.  Description of familial keloids in five pedigrees: evidence for autosomal dominant inheritance and phenotypic heterogeneity 
BMC Dermatology  2009;9:8.
Familial keloids have been reported, having either autosomal dominant or autosomal recessive inheritance. We wished to determine the inheritance pattern and phenotype of keloids among multigenerational families, as a prelude to a positional mapping strategy to identify candidate genes.
We studied three African American families, one Afro-Caribbean family and one Asian-American family. Phenotyping including assessing all patients for the presence, distribution, and appearance of keloids, together with the timing of keloid onset and provocative factors. The clinical trial was registered at (NCT 00005802).
Age of keloid onset varied considerably within families, but commonly occurred by the second decade. The fraction of affected individuals was 38%, 45%, 62%, 67% and 73% among the five families respectively. Keloid severity and morphology differed within and between families. A novel finding is that certain families manifest keloids in distinct locations, with one family showing an excess of extremity keloids and two families showing an excess of axilla-groin keloids.
Familial keloids appear to most commonly manifest autosomal dominant or semidominant inheritance, and there may be familial patterns of keloid distribution.
PMCID: PMC2724379  PMID: 19638218
15.  The Greig cephalopolysyndactyly syndrome 
The Greig cephalopolysyndactyly syndrome (GCPS) is a pleiotropic, multiple congenital anomaly syndrome. It is rare, but precise estimates of incidence are difficult to determine, as ascertainment is erratic (estimated range 1–9/1,000,000). The primary findings include hypertelorism, macrocephaly with frontal bossing, and polysyndactyly. The polydactyly is most commonly preaxial of the feet and postaxial in the hands, with variable cutaneous syndactyly, but the limb findings vary significantly. Other low frequency findings include central nervous system (CNS) anomalies, hernias, and cognitive impairment.
GCPS is caused by loss of function mutations in the GLI3 transcription factor gene and is inherited in an autosomal dominant pattern. The disorder is allelic to the Pallister-Hall syndrome and one form of the acrocallosal syndrome.
Clinical diagnosis is challenging because the findings of GCPS are relatively non-specific, and no specific and sensitive clinical have been delineated. For this reason, we have proposed a combined clinical-molecular definition for the syndrome. A presumptive diagnosis of GCPS can be made if the patient has the classic triad of preaxial polydactyly with cutaneous syndactyly of at least one limb, hypertelorism, and macrocephaly. Patients with a phenotype consistent with GCPS (but which may not manifest all three attributes listed above) and a GLI3 mutation may be diagnosed definitively with GCPS. In addition, persons with a GCPS-consistent phenotype who are related to a definitively diagnosed family member in a pattern consistent with autosomal dominant inheritance may be diagnosed definitively as well. Antenatal molecular diagnosis is technically straightforward to perform.
Differential diagnoses include preaxial polydactyly type 4, the GCPS contiguous gene syndrome, acrocallosal syndrome, Gorlin syndrome, Carpenter syndrome, and Teebi syndrome.
Treatment of the disorder is symptomatic, with plastic or orthopedic surgery indicated for significant limb malformations.
The prognosis for typically affected patients is excellent. There may be a slight increase in the incidence of developmental delay or cognitive impairment. Patients with large deletions that include GLI3 may have a worse prognosis.
The Article is a work of the United States Government. Title 17 U.S.C 5 105 provides that copyright protection is not available for any work of the United States Government in the United States. The United States hereby grants to anyone a paid-up, nonexclusive, irrevocable worldwide license to reproduce, prepare derivative works, distribute copies to the public and perform publicly and display publicly the work, and also retains the nonexclusive right to do all of the above for or on behalf of the United States.
PMCID: PMC2397380  PMID: 18435847
The Lancet. Neurology  2012;11(12):1048-1056.
We previously detected functional brain imaging abnormalities in young adults at genetic risk for late-onset Alzheimer’s disease (AD). Here, we sought to characterize structural and functional magnetic resonance imaging (MRI), cerebrospinal fluid (CSF), and plasma biomarker abnormalities in young adults at risk for autosomal dominant early-onset AD. Biomarker measurements were characterized and compared in presenilin 1 (PSEN1) E280A mutation carriers and non-carriers from the world’s largest known autosomal dominant early-onset AD kindred, more than two decades before the carriers’ estimated median age of 44 at the onset of mild cognitive impairment (MCI) and before their estimated age of 28 at the onset of amyloid-β (Aβ) plaque deposition.
Biomarker data for this cross-sectional study were acquired in Antioquia, Colombia between July and August, 2010. Forty-four participants from the Colombian Alzheimer’s Prevention Initiative (API) Registry had structural MRIs, functional MRIs during associative memory encoding/novel viewing and control tasks, and cognitive assessments. They included 20 mutation carriers and 24 non-carriers, who were cognitively normal, 18-26 years old and matched for their gender, age, and educational level. Twenty of the participants, including 10 mutation carriers and 10 non-carriers, had lumbar punctures and venipunctures. Primary outcome measures included task-dependent hippocampal/parahippocampal activations and precuneus/posterior cingulate deactivations, regional gray matter reductions, CSF Aβ1-42, total tau and phospho-tau181 levels, and plasma Aβ1-42 levels and Aβ1-42/Aβ1-40 ratios. Structural and functional MRI data were compared using automated brain mapping algorithms and AD-related search regions. Cognitive and fluid biomarkers were compared using Mann-Whitney tests.
The mutation carrier and non-carrier groups did not differ significantly in their dementia ratings, neuropsychological test scores, or proportion of apolipoprotein E (APOE) ε4 carriers. Compared to the non-carriers, carriers had higher CSF Aβ1-42 levels (p=0·008), plasma Aβ1-42 levels (p=0·01), and plasma Aβ1-42/Aβ1-40 ratios (p=0·001), consistent with Aβ1-42 overproduction. They also had greater hippocampal/parahippocampal activations (as low as p=0·008, after correction for multiple comparisons), less precuneus/posterior cingulate deactivations (as low as p=0·001, after correction), less gray matter in several regions (p-values <0·005, uncorrected, and corrected p=0·008 in the parietal search region), similar to findings in the later preclinical and clinical stages of autosomal dominant and late-onset AD.
Young adults at genetic risk for autosomal dominant AD have functional and structural MRI abnormalities, along with CSF and plasma biomarker findings consistent with Aβ1-42 over-production. While the extent to which the underlying brain changes are progressive or developmental remain to be determined, this study demonstrates the earliest known biomarker changes in cognitively normal people at genetic risk for autosomal dominant AD.
Banner Alzheimer’s Foundation, Nomis Foundation, Anonymous Foundation, Forget Me Not Initiative, Boston University Department of Psychology, Colciencias (1115-408-20512, 1115-545-31651), National Institute on Aging (R01 AG031581, P30 AG19610, UO1 AG024904, RO1 AG025526, RF1AG041705), National Institute of Neurological Disorders and Stroke (F31-NS078786) and state of Arizona.
PMCID: PMC4181671  PMID: 23137948
Alzheimer’s disease; biomarkers; preclinical; early-onset; dominantly inherited; MRI; functional MRI; cerebrospinal fluid; plasma; presenilin E280A mutation; amyloid; tau; genetics; prevention
17.  Genetic basis of limb-girdle muscular dystrophies: the 2014 update 
Acta Myologica  2014;33(1):1-12.
Limb-girdle muscular dystrophies (LGMD) are a highly heterogeneous group of muscle disorders, which first affect the voluntary muscles of the hip and shoulder areas. The definition is highly descriptive and less ambiguous by exclusion: non-Xlinked, non-FSH, non-myotonic, non-distal, nonsyndromic, and non-congenital. At present, the genetic classification is becoming too complex, since the acronym LGMD has also been used for a number of other myopathic disorders with overlapping phenotypes. Today, the list of genes to be screened is too large for the gene-by-gene approach and it is well suited for targeted next generation sequencing (NGS) panels that should include any gene that has been so far associated with a clinical picture of LGMD. The present review has the aim of recapitulating the genetic basis of LGMD ordering and of proposing a nomenclature for the orphan forms. This is useful given the pace of new discoveries. Thity-one loci have been identified so far, eight autosomal dominant and 23 autosomal recessive. The dominant forms (LGMD1) are: LGMD1A (myotilin), LGMD1B (lamin A/C), LGMD1C (caveolin 3), LGMD1D (DNAJB6), LGMD1E (desmin), LGMD1F (transportin 3), LGMD1G (HNRPDL), LGMD1H (chr. 3). The autosomal recessive forms (LGMD2) are: LGMD2A (calpain 3), LGMD2B (dysferlin), LGMD2C (γ sarcoglycan), LGMD2D (α sarcoglycan), LGMD2E (β sarcoglycan), LGMD2F (δ sarcoglycan), LGMD2G (telethonin), LGMD2H (TRIM32), LGMD2I (FKRP), LGMD2J (titin), LGMD2K (POMT1), LGMD2L (anoctamin 5), LGMD2M (fukutin), LGMD2N (POMT2), LGMD2O (POMTnG1), LGMD2P (dystroglycan), LGMD2Q (plectin), LGMD2R (desmin), LGMD2S (TRAPPC11), LGMD2T (GMPPB), LGMD2U (ISPD), LGMD2V (Glucosidase, alpha ), LGMD2W (PINCH2).
PMCID: PMC4021627  PMID: 24843229
Limb-girdle muscular dystrophies; LGMD; NGS
18.  Cholinesterase Inhibitors in Mild Cognitive Impairment: A Systematic Review of Randomised Trials 
PLoS Medicine  2007;4(11):e338.
Mild cognitive impairment (MCI) refers to a transitional zone between normal ageing and dementia. Despite the uncertainty regarding the definition of MCI as a clinical entity, clinical trials have been conducted in the attempt to study the role of cholinesterase inhibitors (ChEIs) currently approved for symptomatic treatment of mild to moderate Alzheimer disease (AD), in preventing progression from MCI to AD. The objective of this review is to assess the effects of ChEIs (donepezil, rivastigmine, and galantamine) in delaying the conversion from MCI to Alzheimer disease or dementia.
Methods and Findings
The terms “donepezil”, “rivastigmine”, “galantamine”, and “mild cognitive impairment” and their variants, synonyms, and acronyms were used as search terms in four electronic databases (MEDLINE, EMBASE, Cochrane, PsycINFO) and three registers: the Cochrane Collaboration Trial Register, Current Controlled Trials, and Published and unpublished studies were included if they were randomized clinical trials published (or described) in English and conducted among persons who had received a diagnosis of MCI and/or abnormal memory function documented by a neuropsychological assessment. A standardized data extraction form was used. The reporting quality was assessed using the Jadad scale. Three published and five unpublished trials met the inclusion criteria (three on donepezil, two on rivastigmine, and three on galantamine). Enrolment criteria differed among the trials, so the study populations were not homogeneous. The duration of the trials ranged from 24 wk to 3 y. No significant differences emerged in the probability of conversion from MCI to AD or dementia between the treated groups and the placebo groups. The rate of conversion ranged from 13% (over 2 y) to 25% (over 3 y) among treated patients, and from 18% (over 2 y) to 28% (over 3 y) among those in the placebo groups. Only for two studies was it possible to derive point estimates of the relative risk of conversion: 0.85 (95% confidence interval 0.64–1.12), and 0.84 (0.57–1.25). Statistically significant differences emerged for three secondary end points. However, when adjusting for multiple comparisons, only one difference remained significant (i.e., the rate of atrophy in the whole brain).
The use of ChEIs in MCI was not associated with any delay in the onset of AD or dementia. Moreover, the safety profile showed that the risks associated with ChEIs are not negligible. The uncertainty regarding MCI as a clinical entity raises the question as to the scientific validity of these trials.
A systematic review of trials of cholinesterase inhibitors for preventing transition of mild cognitive impairment (MCI) to dementia, conducted by Roberto Raschetti and colleagues, found no difference between treatment and control groups and concluded that uncertainty regarding the definition of MCI casts doubts on the validity of such trials.
Editors' Summary
Worldwide, more than 24 million people have dementia, a group of brain disorders characterized by an irreversible decline in memory, problem solving, communication, and other “cognitive” functions. The commonest form of dementia is Alzheimer disease (AD). The risk of developing AD increases with age—AD is rare in people younger than 65 but about half of people over 85 years old have it. The earliest symptom of AD is usually difficulty in remembering new information. As the disease progresses, patients may become confused and have problems expressing themselves. Their behavior and personality can also change. In advanced AD, patients need help with daily activities like dressing and eating, and eventually lose their ability to recognize relatives and to communicate. There is no cure for AD but a class of drugs called “cholinesterase inhibitors” can sometimes temporarily slow the worsening of symptoms. Three cholinesterase inhibitors—donepezil, rivastigmine, and galantamine—are currently approved for use in mild-to-moderate AD.
Why Was This Study Done?
Some experts have questioned the efficacy of cholinesterase inhibitors in AD, but other experts and patient support groups have called for these drugs to be given to patients with a condition called mild cognitive impairment (MCI) as well as to those with mild AD. People with MCI have memory problems that are more severe than those normally seen in people of their age but no other symptoms of dementia. They are thought to have an increased risk of developing AD, but it is not known whether everyone with MCI eventually develops AD, and there is no standardized way to diagnose MCI. Despite these uncertainties, several clinical trials have investigated whether cholinesterase inhibitors prevent progression from MCI to AD. In this study, the researchers have assessed whether the results of these trials provide any evidence that cholinesterase inhibitors can prevent MCI progressing to AD.
What Did the Researchers Do and Find?
The researchers conducted a systematic review of the medical literature to find trials that had addressed this issue, which met criteria that they had defined clearly in advance of their search. They identified three published and five unpublished randomized controlled trials (studies in which patients randomly receive the test drug or an inactive placebo) that investigated the effect of cholinesterase inhibitors on the progression of MCI. The researchers obtained the results of six of these trials—four examined the effect of cholinesterase inhibitors on the conversion of MCI to clinically diagnosed AD or dementia (the primary end point); all six examined the effect of the drugs on several secondary end points (for example, individual aspects of cognitive function). None of the drugs produced a statistically significant difference (a difference that is unlikely to have happened by chance) in the probability of progression from MCI to AD. The only statistically significant secondary end point after adjustment for multiple comparisons (when many outcomes are considered, false positive results can occur unless specific mathematical techniques are used to prevent this problem) was a decrease in the rate of brain shrinkage associated with galantamine treatment. More patients treated with cholinesterase inhibitors dropped out of trials because of adverse effects than patients given placebo. Finally, in the one trial that reported all causes of deaths, one participant who received placebo and six who received galantamine died.
What Do These Findings Mean?
These findings suggest that the use of cholinesterase inhibitors is not associated with any delay in the onset of clinically diagnosed AD or dementia in people with MCI. They also show that the use of these drugs has no effect on most surrogate (substitute) indicators of AD but that the risks associated with their use are not negligible. However, because MCI has not yet been clearly defined as a clinical condition that precedes dementia, some (even many) of the patients enrolled into the trials that the researchers assessed may not actually have had MCI. Thus, further clinical trials are needed to clarify whether cholinesterase inhibitors can delay the progression of MCI to dementia, but these additional trials should not be done until the diagnosis of MCI has been standardized.
Additional Information.
Please access these Web sites via the online version of this summary at
An essay by Matthews and colleagues, in the October 2007 issue of PLoS Medicine, discusses how mild cognitive impairment is currently diagnosed
The US Alzheimer's Association provides information about all aspects of Alzheimer disease, including fact sheets on treatments for Alzheimer disease and on mild cognitive impairment
The UK Alzheimer's Society provides information for patients and caregivers on all aspects of dementia, including drug treatments and mild cognitive impairment
The UK charity DIPEx provides short video clips of personal experiences of care givers of people with dementia
PMCID: PMC2082649  PMID: 18044984
19.  A novel COL4A1 gene mutation results in autosomal dominant non-syndromic congenital cataract in a Chinese family 
BMC Medical Genetics  2014;15:97.
Almost one-third of congenital cataracts are primarily autosomal dominant disorders, which are also called autosomal dominant congenital cataract, resulting in blindness and clouding of the lens. The purpose of this study was to identify the disease-causing mutation in a Chinese family affected by bilateral, autosomal dominant congenital cataract.
The detection of candidate gene mutation and the linkage analysis of microsatellite markers were performed for the known candidate genes. Molecular mapping and cloning of candidate genes were used in all affected family members to screen for potential genetic mutations and the mutation was confirmed by single enzyme digestion.
The proband was diagnosed with isolated, congenital cataract without the typical clinical manifestations of cataract, which include diabetes, porencephaly, sporadic intracerebral hemorrhage, and glomerulopathy. A novel mutation, c.2345 G > C (Gly782Ala), in exon 31 of the collagen type IV αlpha1 (COL4A1) gene, which encodes the collagen alpha-1(IV) chain, was found to be associated with autosomal dominant congenital cataract in a Chinese family. This mutation was not found in unaffected family members or in 200 unrelated controls. Sequence analysis confirmed that the Gly782 amino acid residue is highly conserved.
The novel mutation (c.2345 G > C) of the COL4A1 gene is the first report of a non-syndromic, autosomal dominant congenital cataract, thereby highlighting the important role of type IV collagen in the physiological and optical properties of the lens.
PMCID: PMC4236509  PMID: 25124159
Type IV collagen; COL4A1; Non-syndromic congenital cataract
20.  Differences in Reporting of Analyses in Internal Company Documents Versus Published Trial Reports: Comparisons in Industry-Sponsored Trials in Off-Label Uses of Gabapentin 
PLoS Medicine  2013;10(1):e1001378.
Using documents obtained through litigation, S. Swaroop Vedula and colleagues compared internal company documents regarding industry-sponsored trials of off-label uses of gabapentin with the published trial reports and find discrepancies in reporting of analyses.
Details about the type of analysis (e.g., intent to treat [ITT]) and definitions (i.e., criteria for including participants in the analysis) are necessary for interpreting a clinical trial's findings. Our objective was to compare the description of types of analyses and criteria for including participants in the publication (i.e., what was reported) with descriptions in the corresponding internal company documents (i.e., what was planned and what was done). Trials were for off-label uses of gabapentin sponsored by Pfizer and Parke-Davis, and documents were obtained through litigation.
Methods and Findings
For each trial, we compared internal company documents (protocols, statistical analysis plans, and research reports, all unpublished), with publications. One author extracted data and another verified, with a third person verifying discordant items and a sample of the rest. Extracted data included the number of participants randomized and analyzed for efficacy, and types of analyses for efficacy and safety and their definitions (i.e., criteria for including participants in each type of analysis). We identified 21 trials, 11 of which were published randomized controlled trials, and that provided the documents needed for planned comparisons. For three trials, there was disagreement on the number of randomized participants between the research report and publication. Seven types of efficacy analyses were described in the protocols, statistical analysis plans, and publications, including ITT and six others. The protocol or publication described ITT using six different definitions, resulting in frequent disagreements between the two documents (i.e., different numbers of participants were included in the analyses).
Descriptions of analyses conducted did not agree between internal company documents and what was publicly reported. Internal company documents provide extensive documentation of methods planned and used, and trial findings, and should be publicly accessible. Reporting standards for randomized controlled trials should recommend transparent descriptions and definitions of analyses performed and which study participants are excluded.
Please see later in the article for the Editors' Summary
Editors' Summary
To be credible, published research must present an unbiased, transparent, and accurate description of the study methods and findings so that readers can assess all relevant information to make informed decisions about the impact of any conclusions. Therefore, research publications should conform to universally adopted guidelines and checklists. Studies to establish whether a treatment is effective, termed randomized controlled trials (RCTs), are checked against a comprehensive set of guidelines: The robustness of trial protocols are measured through the Standard Protocol Items for Randomized Trials (SPIRIT), and the Consolidated Standards of Reporting Trials (CONSORT) statement (which was constructed and agreed by a meeting of journal editors in 1996, and has been updated over the years) includes a 25-point checklist that covers all of the key points in reporting RCTs.
Why Was This Study Done?
Although the CONSORT statement has helped improve transparency in the reporting of the methods and findings from RCTs, the statement does not define how certain types of analyses should be conducted and which patients should be included in the analyses, for example, in an intention-to-treat analysis (in which all participants are included in the data analysis of the group to which they were assigned, whether or not they completed the intervention given to the group). So in this study, the researchers used internal company documents released in the course of litigation against the pharmaceutical company Pfizer regarding the drug gabapentin, to compare between the internal and published reports the reporting of the numbers of participants, the description of the types of analyses, and the definitions of each type of analysis. The reports involved studies of gabapentin used for medical reasons not approved for marketing by the US Food and Drug Administration, known as “off-label” uses.
What Did the Researchers Do and Find?
The researchers identified trials sponsored by Pfizer relating to four off-label uses of gabapentin and examined the internal company protocols, statistical analysis plans, research reports, and the main publications related to each trial. The researchers then compared the numbers of participants randomized and analyzed for the main (primary) outcome and the type of analysis for efficacy and safety in both the internal research report and the trial publication. The researchers identified 21 trials, 11 of which were published RCTs that had the associated documents necessary for comparison.
The researchers found that in three out of ten trials there were differences in the internal research report and the main publication regarding the number of randomized participants. Furthermore, in six out of ten trials, the researchers were unable to compare the internal research report with the main publication for the number of participants analyzed for efficacy, because the research report either did not describe the primary outcome or did not describe the type of analysis. Overall, the researchers found that seven different types of efficacy analyses were described in the protocols, statistical analysis plans, and publications, including intention-to-treat analysis. However, the protocol or publication used six different descriptions for the intention-to-treat analysis, resulting in several important differences between the internal and published documents about the number of patients included in the analysis.
What Do These Findings Mean?
These findings from a sample of industry-sponsored trials on the off-label use of gabapentin suggest that when compared to the internal research reports, the trial publications did not always accurately reflect what was actually done in the trial. Therefore, the trial publication could not be considered to be an accurate and transparent record of the numbers of participants randomized and analyzed for efficacy. These findings support the need for further revisions of the CONSORT statement, such as including explicit statements about the criteria used to define each type of analysis and the numbers of participants excluded from each type of analysis. Further guidance is also needed to ensure consistent terminology for types of analysis. Of course, these revisions will improve reporting only if authors and journals adhere to them. These findings also highlight the need for all individual patient data to be made accessible to readers of the published article.
Additional Information
Please access these Web sites via the online version of this summary at
For more information, see the CONSORT statement website
The EQUATOR Network website is a resource center for the good reporting of health research studies and has more information about the SPIRIT initiative and the CONSORT statement
PMCID: PMC3558476  PMID: 23382656
21.  Ghost Authorship in Industry-Initiated Randomised Trials 
PLoS Medicine  2007;4(1):e19.
Ghost authorship, the failure to name, as an author, an individual who has made substantial contributions to an article, may result in lack of accountability. The prevalence and nature of ghost authorship in industry-initiated randomised trials is not known.
Methods and Findings
We conducted a cohort study comparing protocols and corresponding publications for industry-initiated trials approved by the Scientific-Ethical Committees for Copenhagen and Frederiksberg in 1994–1995. We defined ghost authorship as present if individuals who wrote the trial protocol, performed the statistical analyses, or wrote the manuscript, were not listed as authors of the publication, or as members of a study group or writing committee, or in an acknowledgment. We identified 44 industry-initiated trials. We did not find any trial protocol or publication that stated explicitly that the clinical study report or the manuscript was to be written or was written by the clinical investigators, and none of the protocols stated that clinical investigators were to be involved with data analysis. We found evidence of ghost authorship for 33 trials (75%; 95% confidence interval 60%–87%). The prevalence of ghost authorship was increased to 91% (40 of 44 articles; 95% confidence interval 78%–98%) when we included cases where a person qualifying for authorship was acknowledged rather than appearing as an author. In 31 trials, the ghost authors we identified were statisticians. It is likely that we have overlooked some ghost authors, as we had very limited information to identify the possible omission of other individuals who would have qualified as authors.
Ghost authorship in industry-initiated trials is very common. Its prevalence could be considerably reduced, and transparency improved, if existing guidelines were followed, and if protocols were publicly available.
Of 44 industry-initiated trials, there was evidence of ghost authorship in 33, increasing to 40 when a person qualifying for authorship was acknowledged rather than appearing as an author.
Editors' Summary
Original scientific findings are usually published in the form of a “paper”, whether it is actually distributed on paper, or circulated via the internet, as this one is. Papers are normally prepared by a group of researchers who did the research and are then listed at the top of the article. These authors therefore take responsibility for the integrity of the results and interpretation of them. However, many people are worried that sometimes the author list on the paper does not tell the true story of who was involved. In particular, for clinical research, case histories and previous research has suggested that “ghost authorship” is commonplace. Ghost authors are people who were involved in some way in the research study, or writing the paper, but who have been left off the final author list. This might happen because the study “looks” more credible if the true authors (for example, company employees or freelance medical writers) are not revealed. This practice might hide competing interests that readers should be aware of, and has therefore been condemned by academics, groups of editors, and some pharmaceutical companies.
Why Was This Study Done?
This group of researchers wanted to get an idea of how often ghost authorship happened in medical research done by companies. Previous studies looking into this used surveys, whereby the researchers would write to one author on each of a group of papers to ask whether anyone else had been involved in the work but who was not listed on the paper. These sorts of studies typically underestimate the rate of ghost authorship, because the main author might not want to admit what had been going on. However, the researchers here managed to get access to trial protocols (documents setting out the plans for future research studies), which gave them a way to investigate ghost authorship.
What Did the Researchers Do and Find?
In order to investigate the frequency and type of ghost authorship, these researchers identified every trial which was approved between 1994 and 1995 by the ethics committees of Copenhagen and Frederiksberg in Denmark. Then they winnowed this group down to include only the trials that were sponsored by industry (pharmaceutical companies and others), and only those trials that were finished and published. The protocols for each trial were obtained from the ethics committees and the researchers then matched up each protocol with its corresponding paper. Then, they compared names which appeared in the protocol against names appearing on the eventual paper, either on the author list or acknowledged elsewhere in the paper as being involved. The researchers ended up studying 44 trials. For 31 of these (75% of them) they found some evidence of ghost authorship, in that people were identified as having written the protocol or who had been involved in doing statistical analyses or writing the manuscript, but did not end up listed in the manuscript. If the definition of authorship was made narrower, and “ghost authorship” included people qualifying for authorship who were mentioned in the acknowledgements but not the author list, the researchers' estimate went up to 91%, that is 40 of the 44 trials. For most of the trials with missing authors, the ghost was a statistician (the person who analyzes the trial data).
What Do These Findings Mean?
In this study, the researchers found that ghost authorship was very common in papers published in medical journals (this study covered a broad range of peer-reviewed journals in many medical disciplines). The method used in this paper seems more reliable than using surveys to work out how often ghost authorship happens. The researchers aimed to define authorship using the policies set out by a group called the International Committee of Medical Journal Editors (ICMJE), and the findings here suggest that the ICMJE's standards for authorship are very often ignored. This means that people who read the published paper cannot always accurately judge or trust the information presented within it, and competing interests may be hidden. The researchers here suggest that protocols should be made publicly available so that everyone can see what trials are planned and who is involved in conducting them. The findings also suggest that journals should not only list the authors of each paper but describe what each author has done, so that the published information accurately reflects what has been carried out.
Additional Information.
Please access these Web sites via the online version of this summary at
Read the Perspective by Liz Wager, which discusses these findings in more depth
The International Committee of Medical Journal Editors (ICMJE) is a group of general medical journal editors who have produced general guidelines for biomedical manuscripts; their definition of authorship is also described
The Committee on Publication Ethics is a forum for editors of peer-reviewed journals to discuss issues related to the integrity of the scientific record; the Web site lists anonymized problems and the committee's advice, not just regarding authorship, but other types of problems as well
Good Publication Practice for Pharmaceutical Companies outlines common standards for publication of industry-sponsored medical research, and some pharmaceutical companies have agreed to these
PMCID: PMC1769411  PMID: 17227134
22.  Spastic paraplegia gene 7 in patients with spasticity and/or optic neuropathy 
Brain  2012;135(10):2980-2993.
Mutations in the spastic paraplegia 7 (SPG7) gene encoding paraplegin are responsible for autosomal recessive hereditary spasticity. We screened 135 unrelated index cases, selected in five different settings: SPG7-positive patients detected during SPG31 analysis using SPG31/SPG7 multiplex ligation-dependent probe amplification (n = 7); previously reported ambiguous SPG7 cases (n = 5); patients carefully selected on the basis of their phenotype (spasticity of the lower limbs with cerebellar signs and/or cerebellar atrophy on magnetic resonance imaging/computer tomography scan and/or optic neuropathy and without other signs) (n = 24); patients with hereditary spastic paraparesis referred consecutively from attending neurologists and the national reference centre in a diagnostic setting (n = 98); and the index case of a four-generation family with autosomal dominant optic neuropathy but no spasticity linked to the SPG7 locus. We identified two SPG7 mutations in 23/134 spastic patients, 21% of the patients selected according to phenotype but only 8% of those referred directly. Our results confirm the pathogenicity of Ala510Val, which was the most frequent mutation in our series (65%) and segregated at the homozygous state with spastic paraparesis in a large family with autosomal recessive inheritance. All SPG7-positive patients tested had optic neuropathy or abnormalities revealed by optical coherence tomography, indicating that abnormalities in optical coherence tomography could be a clinical biomarker for SPG7 testing. In addition, the presence of late-onset very slowly progressive spastic gait (median age 39 years, range 18–52 years) associated with cerebellar ataxia (39%) or cerebellar atrophy (47%) constitute, with abnormal optical coherence tomography, key features pointing towards SPG7-testing. Interestingly, three relatives of patients with heterozygote SPG7 mutations had cerebellar signs and atrophy, or peripheral neuropathy, but no spasticity of the lower limbs, suggesting that SPG7 mutations at the heterozygous state might predispose to late-onset neurodegenerative disorders, mimicking autosomal dominant inheritance. Finally, a novel missense SPG7 mutation at the heterozygous state (Asp411Ala) was identified as the cause of autosomal dominant optic neuropathy in a large family, indicating that some SPG7 mutations can occasionally be dominantly inherited and be an uncommon cause of isolated optic neuropathy. Altogether, these results emphasize the clinical variability associated with SPG7 mutations, ranging from optic neuropathy to spastic paraplegia, and support the view that SPG7 screening should be carried out in both conditions.
PMCID: PMC3470714  PMID: 23065789
SPG7; hereditary spastic paraparesis; optic neuropathy; cerebellar atrophy, optical coherence tomography
23.  Autosomal dominant polycystic kidney disease with diffuse proliferative glomerulonephritis - an unusual association: a case report and review of the literature 
Autosomal dominant polycystic kidney disease is an inherited disorder that is characterized by the development and growth of cysts in the kidneys and other organs. Urinary protein excretion is usually less than 1 g/24 hours in autosomal dominant polycystic kidney disease, and an association of nephrotic syndrome with this condition is considered rare. There are only anecdotal case reports of autosomal dominant polycystic kidney disease associated with nephrotic syndrome, with focal segmental glomerulosclerosis being the most commonly reported histopathological diagnosis. Nephrotic-range proteinuria in the presence of autosomal dominant polycystic kidney disease, with or without an accompanying decline in renal function, should be investigated by open renal biopsy to exclude coexisting glomerular disease. To the best of our knowledge, this is the first case of autosomal dominant polycystic kidney disease with histologically proven diffuse proliferative glomerulonephritis presenting with nephrotic-range proteinuria. No other reports of this could be found in a global electronic search of the literature.
Case presentation
We report the case of a 35-year-old Indo-Aryan man with autosomal dominant polycystic kidney disease associated with nephrotic syndrome and a concomitant decline in his glomerular filtration rate. Open renal biopsy revealed diffuse proliferative glomerulonephritis. An accurate diagnosis enabled us to manage him conservatively with a successful outcome, without the use of corticosteroid which is the standard treatment and the drug most commonly used to treat nephrotic syndrome empirically.
Despite the reluctance of physicians to carry out a renal biopsy on patients with autosomal dominant polycystic kidney disease, our case supports the idea that renal biopsy is needed in patients with polycystic kidney disease with nephrotic-range proteinuria to make an accurate diagnosis. It also illustrates the importance of open renal biopsy in planning appropriate treatment for patients with autosomal dominant polycystic kidney disease with nephrotic-range proteinuria. The treatment for various histological subtypes leading to nephrotic syndrome is different, and in this modern era we should practice evidence-based medicine and should avoid empirical therapy with its associated adverse effects.
PMCID: PMC2873454  PMID: 20429898
24.  Surgery Versus Epilation for the Treatment of Minor Trichiasis in Ethiopia: A Randomised Controlled Noninferiority Trial 
PLoS Medicine  2011;8(12):e1001136.
In this randomized, non-inferiority trial, Saul Rajak et al compare epilation and surgery for the management of minor trichiasis in Ethiopia, the country with the most cases of trachomatous trichiasis.
Trachomatous trichiasis can cause corneal damage and visual impairment. WHO recommends surgery for all cases. However, in many regions surgical provision is inadequate and patients frequently decline. Self-epilation is common and was associated with comparable outcomes to surgery in nonrandomised studies for minor trichiasis (
Methods and Findings
1,300 individuals with minor trichiasis from Amhara Regional State, Ethiopia were recruited and randomly assigned (1∶1) to receive trichiasis surgery or epilation. The epilation group were given new forceps and epilation training. The surgical group received trichiasis surgery. Participants were examined every 6 months for 2 years by clinicians masked to allocation, with 93.5% follow-up at 24 months. The primary outcome measure (“failure”) was ≥five lashes touching the eye or receiving trichiasis surgery during 24 months of follow-up, and was assessed for noninferiority with a 10% prespecified noninferiority margin. Secondary outcomes included number of lashes touching, time to failure, and changes in visual acuity and corneal opacity.
Cumulative risk of failure over 24 months was 13.2% in the epilation group and 2.2% in the surgical group (risk difference = 11%). The 95% confidence interval (8.1%–13.9%) includes the 10% noninferiority margin. Mean number of lashes touching the eye was greater in the epilation group than the surgery group (at 24 months 0.95 versus 0.09, respectively; p<0.001); there was no difference in change in visual acuity or corneal opacity between the two groups.
This trial was inconclusive regarding inferiority of epilation to surgery for the treatment of minor trichiasis, relative to the prespecified margin. Epilation had a comparable effect to surgery on visual acuity and corneal outcomes. We suggest that surgery be performed whenever possible but epilation be used for treatment of minor trichiasis patients without access to or declining surgery.
Trial registration NCT00522912
Please see later in the article for the Editors' Summary
Editors' Summary
About 40 million people are affected at any one time by active trachoma, an infectious eye disease caused by the bacterium Chlamydia trachomatis. Trachoma, which is responsible for more than 3% of the world's blindness, mostly affects people living in rural areas in developing countries where there are water shortages, poor personal hygiene, and crowded living conditions. C. trachomatis is spread through contact with infected eye secretions or with contaminated towels or clothes, and by flies. Recurrent infections with C. trachomatis during childhood cause inflammation of the lining of the eye lid (chronic conjunctival inflammation), which can lead to conjunctival scarring. If this scarring is severe, the eyelids turn inwards and the eye lashes rub across the eye's surface (the cornea). This condition—trachomatous trichiasis—is extremely painful. Patients describe the pain like having thorns scraping their eyes when they blink. If left untreated, trichiasis can lead to irreversible corneal opacities and visual impairment.
Why Was This Study Done?
The SAFE strategy—surgery for trichiasis, antibiotics for infection, and facial cleanliness and environmental improvements to reduce transmission—aims to control trachoma in countries where it is common. Unfortunately, current surgical activity is only keeping up with new cases of trichiasis; it is not clearing the backlog. The reasons for this treatment gap are complex but in many regions surgical provision is inadequate. Moreover, although the World Health Organization recommends surgery for all cases of trachomatous trichiasis, people with minor trichiasis (only a few eyelashes touching the cornea) often decline surgery, preferring to pull out their eyelashes (epilation), an intervention that has to be repeated when the eyelashes regrow. In this randomized, noninferiority trial, the researchers compare epilation and surgery for the management of minor trichiasis in Ethiopia, the country with the most cases of trachomatous trichiasis. In a randomized trial, randomly chosen groups of patients are given different treatments for a disease and then followed to compare the outcomes of these interventions. A noninferiority trial investigates whether one treatment is not worse than another treatment.
What Did the Researchers Do and Find?
The researchers randomly assigned 1,300 Ethiopians with minor trichiasis to receive surgery or to be given epilation training and good quality epilation forceps. The primary trial outcome was “failure”—five or more lashes touching the eye or receiving trichiasis surgery during the 24-month follow-up period. The researchers decided in advance that epilation would be deemed noninferior to surgery if its failure rate was less than 10% greater than that of surgery (a noninferiority margin of 10%). Secondary outcomes included the number of lashes touching the eye and changes in visual acuity and corneal opacity. The cumulative risk of failure over 24 months was 13.2% in the epilation group and 2.2% in the surgical group, a difference of 11%. The 95% confidence interval for this difference was 8.1%–13.9%. That is, there was a 95% probability that the true failure rate lay within this range. The mean number of lashes touching the eye at 24 months was 0.95 and 0.09 in the epilation and surgery groups, respectively, a significant difference (that is, a difference unlikely to have occurred by chance). Finally, the changes in visual acuity or corneal opacity during the trial were similar in the two groups.
What Do These Findings Mean?
Because the 95% confidence interval for the difference in failure rate of the two interventions included the preset inferiority margin, these findings provide no evidence that epilation is noninferior to surgery for the management of minor trichiasis. That is, statistically speaking, this trial is inconclusive. Thus, if one were to consider only the primary clinical outcome when deciding whether to include epilation in the management of mild trichiasis, one would reject it because this trial indicates that surgery is better than epilation at preventing lashes touching the eye. However, epilation had a comparable effect to surgery on visual acuity and corneal opacity changes and, importantly, in real life, surgical services are likely to remain unacceptable, unavailable, inaccessible, or prohibitively expensive for many people with trachomatous trichiasis in the medium term. The researchers suggest, therefore, that surgery should be performed for minor trachomatous trichiasis whenever possible but that epilation should be considered when surgery is not available or is declined by the patient.
Additional Information
Please access these Web sites via the online version of this summary at 10.1371/journal.pmed.1001136.
An accompanying PLoS Medicine Research Article by Saul Rajak et al. describes another randomized trial undertaken by these researchers that compares the use of absorbable and silk sutures for the surgical treatment of trachomatous trichiasis in Ethiopia
The World Health Organization has information on trachoma (in several languages), including details of the Alliance for Global Elimination of Trachoma by the year 2020 (GET 2020) and a personal story about blinding trachoma
The UK National Health Service Choices web site also provides information on trachoma
Orbis, an international nonprofit organization devoted to blindness prevention and treatment in developing countries, provides information about trachoma
The International Trachoma Initiative provides detailed personal story about trichiasis surgery in Ethiopia information about trachoma and a personal story about trichiasis surgery in Ethiopia
The Global Atlas of Trachoma is an open-access resource on the geographical distribution of trachoma
Light for the World is a nonprofit organization dedicated to ensuring the rights of persons with disabilities in developing countries, including people in Ethiopia with trachoma
PMCID: PMC3236738  PMID: 22180731
PLoS Medicine  2009;6(9):e1000144.
Joseph Ross and colleagues examine publication rates of clinical trials and find low rates of publication even following registration in
Background is a publicly accessible, Internet-based registry of clinical trials managed by the US National Library of Medicine that has the potential to address selective trial publication. Our objectives were to examine completeness of registration within and to determine the extent and correlates of selective publication.
Methods and Findings
We examined reporting of registration information among a cross-section of trials that had been registered at after December 31, 1999 and updated as having been completed by June 8, 2007, excluding phase I trials. We then determined publication status among a random 10% subsample by searching MEDLINE using a systematic protocol, after excluding trials completed after December 31, 2005 to allow at least 2 y for publication following completion. Among the full sample of completed trials (n = 7,515), nearly 100% reported all data elements mandated by, such as intervention and sponsorship. Optional data element reporting varied, with 53% reporting trial end date, 66% reporting primary outcome, and 87% reporting trial start date. Among the 10% subsample, less than half (311 of 677, 46%) of trials were published, among which 96 (31%) provided a citation within of a publication describing trial results. Trials primarily sponsored by industry (40%, 144 of 357) were less likely to be published when compared with nonindustry/nongovernment sponsored trials (56%, 110 of 198; p<0.001), but there was no significant difference when compared with government sponsored trials (47%, 57 of 122; p = 0.22). Among trials that reported an end date, 75 of 123 (61%) completed prior to 2004, 50 of 96 (52%) completed during 2004, and 62 of 149 (42%) completed during 2005 were published (p = 0.006).
Reporting of optional data elements varied and publication rates among completed trials registered within were low. Without greater attention to reporting of all data elements, the potential for to address selective publication of clinical trials will be limited.
Please see later in the article for the Editors' Summary
Editors' Summary
People assume that whenever they are ill, health care professionals will make sure they get the best available treatment. But how do clinicians know which treatment is most appropriate? In the past, clinicians used their own experience to make treatment decisions. Nowadays, they rely on evidence-based medicine—the systematic review and appraisal of the results of clinical trials, studies that investigate the efficacy and safety of medical interventions in people. However, evidence-based medicine can only be effective if all the results from clinical trials are published promptly in medical journals. Unfortunately, the results of trials in which a new drug did not perform better than existing drugs or in which it had unwanted side effects often remain unpublished or only appear in the public domain many years after the drug has been approved for clinical use by the US Food and Drug Administration (FDA) and other governmental bodies.
Why Was This Study Done?
The extent of this “selective” publication, which can impair evidence-based clinical practice, remains unclear but is thought to be substantial. In this study, the researchers investigate the problem of selective publication by systematically examining the extent of publication of the results of trials registered in, a Web-based registry of US and international clinical trials. was established in 2000 by the US National Library of Medicine in response to the 1997 FDA Modernization Act. This act required preregistration of all trials of new drugs to provide the public with information about trials in which they might be able to participate. Mandatory data elements for registration in initially included the trial's title, the condition studied in the trial, the trial design, and the intervention studied. In September 2007, the FDA Amendments Act expanded the mandatory requirements for registration in by making it necessary, for example, to report the trial start date and to report primary and secondary outcomes (the effect of the intervention on predefined clinical measurements) in the registry within 2 years of trial completion.
What Did the Researchers Do and Find?
The researchers identified 7,515 trials that were registered within after December 31, 1999 (excluding phase I, safety trials), and whose record indicated trial completion by June 8, 2007. Most of these trials reported all the mandatory data elements that were required by before the FDA Amendments Act but reporting of optional data elements was less complete. For example, only two-thirds of the trials reported their primary outcome. Next, the researchers randomly selected 10% of the trials and, after excluding trials whose completion date was after December 31, 2005 (to allow at least two years for publication), determined the publication status of this subsample by systematically searching MEDLINE (an online database of articles published in selected medical and scientific journals). Fewer than half of the trials in the subsample had been published, and the citation for only a third of these publications had been entered into Only 40% of industry-sponsored trials had been published compared to 56% of nonindustry/nongovernment-sponsored trials, a difference that is unlikely to have occurred by chance. Finally, 61% of trials with a completion date before 2004 had been published, but only 42% of trials completed during 2005 had been published.
What Do These Findings Mean?
These findings indicate that, over the period studied, critical trial information was not included in the registry. The FDA Amendments Act should remedy some of these shortcomings but only if the accuracy and completeness of the information in is carefully monitored. These findings also reveal that registration in does not guarantee that trial results will appear in a timely manner in the scientific literature. However, they do not address the reasons for selective publication (which may be, in part, because it is harder to publish negative results than positive results), and they are potentially limited by the methods used to discover whether trial results had been published. Nevertheless, these findings suggest that the FDA, trial sponsors, and the scientific community all need to make a firm commitment to minimize the selective publication of trial results to ensure that patients and clinicians have access to the information they need to make fully informed treatment decisions.
Additional Information
Please access these Web sites via the online version of this summary at
PLoS Medicine recently published two related articles on selected publication by Ida Sim and colleagues and by Lisa Bero and colleagues and an editorial discussing the FDA Amendments Act provides information about the US National Institutes of Health clinical trial registry, including background information about clinical trials, and a fact sheet detailing the requirements of the FDA Amendments Act 2007 for trial registration
The US Food and Drug Administration provides further information about drug approval in the US for consumers and health care professionals
PMCID: PMC2728480  PMID: 19901971

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