To determine whether 3-hydroxy-3-methylglutaryl coenzyme A inhibitors (statins) are associated with a decreased risk of colorectal cancer.
The population included 159,219 postmenopausal women enrolled in the Women’s Health Initiative in which 2000 pathologically confirmed cases of colorectal cancer were identified during an average of 10.7 (S.D. 2.9) years. Information on statins was collected at baseline and years 1, 3, 6, and 9. Self- and interviewer-administered questionnaires were used to collect information on other risk factors. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated by the use of Cox proportional hazards regression to evaluate the relationship between statin use and risk. Statistical tests were two-sided.
Statins were used by 12,030 (7.6%) women at baseline. The annualized colorectal cancer rate was 0.13% among users and 0.12% among nonusers. The multivariable adjusted HR for users versus nonusers was 0.99 (95% confidence interval [CI], 0.83–1.20, p=.95), and 0.79 (95% CI, 0.56–1.11) for users of ≥3 years. In the multivariable adjusted time-dependent model, the HR for lovastatin was 0.62 (95% CI, 0.39–0.99). There was no effect of tumor location, stage or grade.
There was a reduction in colorectal cancer risk associated with lovastatin and a non-significant association with longer duration of use.
Colorectal Cancer; Statins; Cancer Risk; Cohort Study
The side-effects associated with androgen deprivation therapy (ADT) include weight gain, dyslipidemia, and insulin resistance. As cataracts have been linked to these metabolic abnormalities, an increased risk of cataract may be another adverse consequence of ADT use.
Using data from the Surveillance, Epidemiology and End Results-Medicare database, we estimated risk of cataract associated with ADT among 65,852 prostate-cancer patients. ADT treatment was defined as at least one dose of a gonadotropin-releasing hormone agonist or orchiectomy within 6 months after prostate cancer diagnosis. The outcome measure was a first claim of cataract diagnosis identified in Medicare claim files. Cox regression was used to estimate hazard ratios (HR) for the effects of ADT treatment, controlling for confounders.
Gonadotropin-releasing hormone agonist use was associated with a modest increase in cataract incidence (HR 1.09, 95% confidence interval 1.06–1.12). rchiectomy was also associated with an increased risk of cataract among men with no history of cataract prior to prostate cancer diagnosis (HR 1.26, 95% confidence interval 1.07–1.47).
In the first systematic investigation of the association between ADT and cataract, our results suggest an elevation in the incidence of cataract among ADT users. Further study, preferably prospective in design, is needed to provide additional evidence to support or refute these findings.
Epidemiology; GnRH Agonist; Lens Opacities; Orchiectomy; Prostate Cancer; SEER-Medicare
The mucosa of the small intestine encompasses about 90% of the luminal surface area of the digestive system, but only 2% of the total annual gastrointestinal cancer incidence in the United States.
The remarkable contrast in age-standardized cancer incidence between the small and large intestine has been reviewed with respect to the cell type patterns, demographic features, and molecular characteristics of neoplasms.
Particularly noteworthy is the predominance of adenocarcinoma in the colon, which exceeds 98% of the total incidence by cell type, in contrast to that of 30% to 40% in the small intestine, resulting in an age-standardized ratio of rates exceeding 50-fold. The prevalence of adenomas and carcinomas is most prominent in the duodenum and proximal jejunum. The positive correlation in global incidence rates of small and large intestinal neoplasms and the reciprocal increases in risk of second primary adenocarcinomas suggest that there are common environmental risk factors. The pathophysiology of Crohn inflammatory bowel disease and the elevated risk of adenocarcinoma demonstrate the significance of the impaired integrity of the mucosal barrier and of aberrant immune responses to luminal indigenous and potentially pathogenic microorganisms.
In advancing a putative mechanism for the contrasting mucosal susceptibilities of the small and large intestine, substantial differences are underscored in the diverse taxonomy, concentration and metabolic activity of anaerobic organisms, rate of intestinal transit, changing pH, and the enterohepatic recycling and metabolism of bile acids. Experimental and epidemiologic studies are cited that suggest that the changing microecology, particularly in the colon, is associated with enhanced metabolic activation of ingested and endogenously formed procarcinogenic substrates.
Cancer Epidemiology; Molecular Biology; Neuroendocrine Tumor; Adenocarcinoma; Non-Hodgkin Lymphoma; Gastrointestinal Stromal Tumor; Crohn Disease; Celiac Disease; Microbial Flora; Bile Acid Metabolism
To investigate and quantify the impact of moderate lead exposure on students' ability to score at the “proficient” level on end-of-grade standardized tests.
We compared the scores of 3757 fourth grade students from Milwaukee, Wisconsin, on the Wisconsin Knowledge and Concepts Exam (WKCE). The sample consisted of children with a blood lead test before age 3 years that was either unquantifiable at the time of testing (<5 μg/dL) or in the range of moderate exposure (10–19 μg/dL).
After controlling for gender, poverty, English language learner status, race/ethnicity, school disciplinary actions, and attendance percentage, results showed a significant negative effect of moderate lead exposure on academic achievement for all 5 subtests of the WKCE. Test score deficits owing to lead exposure were equal to 22% of the interval between student categorization at the “proficient” or “basic” levels in Reading, and 42% of the interval in Mathematics.
Children exposed to amounts of lead before age 3 years that are insufficient to trigger intervention under current policies in many states are nonetheless at a considerable educational disadvantage compared with their unexposed peers 7 to 8 years later. Exposed students are at greater risk of scoring below the proficient level, an outcome with serious negative consequences for both the student and the school.
Lead poisoning; Lead exposure; Childhood; School; Testing; Environmental pollutants; Environmental pollution; Environmental policy
To examine whether menarcheal age was inversely associated with CVD mortality in Singaporean Chinese women.
34,022 Chinese women aged 45–74 at enrollment (1993–1998), with complete data on study variables, were followed prospectively through 2009 for primary cause of death due to CVD, including coronary heart disease (CHD) and cerebrovascular disease (CERE). Hazard ratios (HRs) for CVD mortality were computed across menarcheal age categories and adjusted for potential confounders and BMI.
Over 460,374 person-years of follow-up, 1,852 women died from CVD; 998 of them from CHD and 557 from CERE. There was a significant interaction between menarcheal age and smoking (p<0.05). In nonsmokers, menarcheal age was inversely associated with risk for CVD and CHD mortality. HRs (and 95% CI) for CVD mortality across menarcheal age categories (≤12, 13–14, 15–16, ≥17) were: 1.06 (0.87–1.29), 1 (referent), 0.89 (0.79–1.00), and 0.80 (0.69–0.93), respectively (ptrend<0.001); HRs for CHD mortality were: 1.06 (0.80–1.34), 1 (referent), 0.76 (0.65–0.90), and 0.72 (0.58–0.88), respectively (ptrend<0.001). In nonsmokers there was no association between menarcheal age and CERE mortality. Among smokers, menarcheal age was not associated with CVD, CHD or CERE mortality.
Menarcheal age was inversely associated with risk of CVD mortality in nonsmoking Chinese women.
Menarche; Cardiovascular Diseases; Coronary Heart Disease; Stroke; Cohort Studies
Recall Bias; Correlation Coefficient; Overweight; Elderly; Body Mass Index
Associations of adiponectin and leptin and their ratio with BMI and HOMA-IR have been investigated in different ethnic groups but variability in both assays and statistical methods have made cross-study comparisons difficult. We examined associations among these variables across four ethnic groups in a single study.
Adiponectin and leptin were measured in a subset of MESA participants. We calculated associations (using both partial correlations and adjusted linear regression) in each ethnic group and then compared the magnitude of these associations across groups.
After excluding individuals with type 2 diabetes there were 714 White, 219 Chinese, 332 African American, and 405 Hispanic individuals, in the study sample. Associations of BMI with adiponectin and leptin differed significantly (P < 0.05) across the ethnic groups in regression analyses, while associations of HOMA-IR with adiponectin and leptin did not differ across ethnic groups. The leptin to adiponectin ratio was not associated with a greater amount of adiposity or HOMA-IR variance than leptin or adiponectin in any ethnic group.
Given the consistency of HOMA-IR and adipokine associations, the differing means of adiponectin and leptin across ethnic groups may help to explain ethnic differences in mean insulin resistance.
To determine the role of type, timing, and cumulative childhood hardships on age at menarche in a prospective cohort study.
Longitudinal analysis of 4,524 female participants of the National Child Development Study cohort (1958 – 2003). Six types of childhood hardships were identified with a factor analysis methodology: financial, family dysfunction, caregiver low interest in education, lack of supportive caregiving, neglectful environment, and family structure disruption. Paternal absence/low involvement in childhood was an a priori hardship. Retrospective reports of abuse in childhood were explored in relation to age at menarche, also. Generalized logit regression analyses explored the impact of type, timing, and cumulative hardships on age at menarche (≤11, 12–13, ≥14 years).
Cumulative childhood hardships were associated with a graded increase in risk for later menarche with adjusted OR [AOR] of 1.37 (95%CI: 1.10, 1.70), 1.50 (95%CI: 1.18, 1.91), and 1.58 (95%CI: 1.29, 1.92) among those with 2, 3, and ≥4 adversities, respectively. More than 2 hardships in early life had the strongest association with late menarche (AOR=2.32, 95%CI: 1.12, 4.80). Sexual abuse was most strongly associated with early menarche (AOR=2.60, 95%CI: 1.40, 4.81).
Cumulative childhood hardships increased risk for later age at menarche. Child abuse was associated with both early and late menarche, although associations varied by type of abuse. Critical period of exposure, type, and chronicity of hardships demonstrate varying degrees of influence on age at menarche.
adversity; birth cohort; child abuse; hardship; life course; menarche; socioeconomic status
Despite growing popularity of Propensity Score (PS) methods used in ethnic disparities studies, many researchers lack clear understanding of when to use PS in place of conventional regression models. One such scenario is presented here: when the relationship between ethnicity and primary care utilization is confounded with and modified by socioeconomic status. Here, standard regression fails to produce an overall disparity estimate, whereas PS methods can through the choice of a reference sample (RS) to which the effect estimate is generalized.
Using data from the National Alcohol Surveys, ethnic disparities between white and Hispanics in access to primary care were estimated using PS methods (PS stratification and weighting), standard logistic regression, and the marginal effects from logistic regression models incorporating effect modification.
Whites, Hispanics and combined white/Hispanic samples were used separately as the RS. Two strategies utilizing PS generated disparities estimates different from those from standard logistic regression, but similar to marginal ORs from logistic regression with ethnicity by covariate interactions included in the model.
When effect modification is present, PS estimates are comparable to marginal estimates from regression models incorporating effect modification. The estimation process requires a-priori hypotheses to guide selection of the RS.
Propensity Scores; multivariable regression; marginal effect; confounding; effect modification; reference sample; disparity
Disparities in the receipt of angiography and subsequent coronary revascularization have not been well-studied.
We estimated prevalence ratios and 95% confidence intervals (PR, 95% CI) for the association between neighborhood-level income (nINC) and receipt of angiography; and among those undergoing angiography, receipt of revascularization procedures, among 9,941 hospitalized myocardial infarction patients under epidemiologic surveillance by the Atherosclerosis Risk in Communities (ARIC) Study (1993–2002).
In analyses by tertile of nINC controlling for age, study community, gender, and year, compared to whites from high nINC areas, blacks from low nINC (0.60, 0.54–0.66) and medium nINC (0.70, 0.60–0.78) areas, as well as whites from low nINC areas (0.83, 0.75–0.91) were less likely to receive angiography, while blacks from high nINC and whites from medium nINC areas were not. Associations were attenuated, but persisted, after controlling for event severity, medical history, receipt of Medicaid, and hospital type. Compared to high nINC whites, blacks were less likely, and whites were as likely, to undergo cardiac revascularization, given receipt of an angiogram.
Black and lower nINC patients were less likely to undergo angiography than were whites and those from higher nINC areas. Among those receiving angiography, race, but not nINC, gradients persisted.
social class; angiography; healthcare disparities
To identify population groups that are most susceptible to obesity-related health conditions at young age.
For this population-based cross-sectional study, measured weight and height, diagnosis, laboratory, and drug prescription information were extracted from electronic medical records of 1,819,205 patients aged 20–39 years enrolled in two integrated health plans in California 2007–2009.
Overall, 29.9% of young adults were obese. Extreme obesity (BMI ≥ 40 kg/m2) was observed in 6.1% of women and 4.5% of men. The adjusted relative risk for diabetes, hypertension, dyslipidemia, and the metabolic syndrome increased sharply for those individuals with a BMI ≥ 40, with the sharpest increase in the adjusted relative risk for hypertension and metabolic syndrome. The association between weight class and dyslipidemia, hypertension and metabolic syndrome but not diabetes was stronger among 20.0–29.9 year olds compared to 30.0–39.9 year olds (p for interaction: <0.05). For example, compared to their normal weight counterparts of the same age group, young adults with a BMI of 40.0–49.9, 50.0–59.9, and ≥60 kg/m2 had a relative risk for hypertension of 11.73, 19.88, and 30.47 (95%-CI 26.39–35.17) at age 20–29 years, and 9.31, 12.41, and 15.43 (95%-CI 14.32–16.63) at age 30–39 years.
While older individuals were more likely to be extremely obese, the association between obesity-related health conditions was stronger in younger individuals. Hispanics and Blacks are also more likely to be obese, including extreme obesity, putting them at an elevated risk for premature cardiovascular disease and some cancers relative to non-Hispanic whites.
Obesity; Type 2 Diabetes Mellitus; Hypercholesterolemia; Metabolic Syndrome X; Hypertension; Young Adult
The current study describes how the excess mortality risk associated with depression translates into specific causes of death occurring during a 40-year follow-up period, with focus on deaths related to injuries, cardiovascular diseases, and cancer.
Data comes from a cross-sectional survey (Community Mental Health Epidemiology Study) conducted in the early 1970s in Washington County, Maryland. Random sampling for the survey resulted in 2762 interviews. For the current analyses, baseline depressed mood was linked to current participant vital status through the use of death certificate records.
The relative subdistribution hazards for cardiovascular deaths (3.08 (1.74–5.45)) and fatal injuries (4.63 (1.76–12.18)) were significant over the entire 40-year period for young adults (18–39 years old at baseline). The relative subdistribution hazard for cardiovascular deaths during the first 15 years of follow-up was pronounced in elderly (≥ 65 years) males (2.99 (1.67–5.37)). There were no significant associations between depressed mood and cancer deaths.
Individuals in the general community with depressed mood may be at increased risk of deaths due to cardiovascular disease and injury, even several decades after exposure assessment. Young adults with depressed mood appear to be particularly vulnerable to these associations.
Depression; depressive symptoms; death; mortality; cardiovascular diseases; wounds and injury
We modeled the age-related trajectory of glucose and determined if cardiorespiratory fitness altered the trajectory in a cohort of men from the Aerobics Center Longitudinal Study.
10,092 men free of diagnosed diabetes, CVD, and cancer, aged 20 to 90 years, completed from 2 to 21 health examinations between 1977 and 2005. Cardiorespiratory fitness was measured by a maximal treadmill exercise test and normalized for age. The covariates included waist circumference, hypertension, elevated cholesterol, smoking behavior and physical activity.
Linear mixed models regression analysis showed that fasting glucose increased at a linear rate with aging. Glucose increased at a yearly rate of 0.17 mg/dL (95% confidence interval: 0.16, 0.19). Fitness had little influence on the aging glucose trajectory below age 35, but significantly influenced the trend after age 35 (P for interaction <0.001). The aging-related glucose increases in low fit men (0.25 mg/dL per year) was higher than average fit (0.15 mg/dL per year) and high fit (0.13 mg/dL per year) men.
The aging-related glucose increases in low fit men was nearly double that of high fit men. Our results may suggest that it is possible to delay the age-related glucose impairment through increasing one’s fitness.
Fasting glucose; aging; physical fitness
Oxidative damage has been implicated in carcinogenesis. We hypothesized that elevated systemic oxidative status would be associated with later occurrence of colorectal adenomatous polyps, a precursor of colorectal cancer.
We examined the prospective association between four systemic markers of oxidative status and colorectal adenomatous polyps within a non-diabetic sub-cohort of the Insulin Resistance Atherosclerosis Study (IRAS) (n=425). Urine samples were collected from 1992–1994 and colorectal adenomas prevalence were assessed in 2002–2004. Oxidative status markers were assessed, which included four F2-isoprostanes (F2-IsoPs) from the classes III and IV: iPF2α-III, 2,3-dinor-iPF2α-III (a metabolite of iPF2α-III), iPF2α-VI, and 8,12-iso-iPF2α-VI. All biomarkers were quantified using liquid chromatography–tandem mass spectrometry. Prospective associations were assessed using multivariate logistic regression analysis.
The adjusted ORs (95% CIs) for occurrence of colorectal adenomatous polyps and scaled to 1 SD of F2-IsoP distribution were 1.16 (0.88–1.50), 0.88 (0.63–1.17), 1.04 (0.80–1.34), and 1.16 (0.90–1.48) for iPF2α-III, iPF2α-VI, 8,12-iso-iPF2α-VI, and 2,3-dinor-iPF2α-III, respectively.
The lack of association between F2-IsoPs and adenomatous polyps does not support the hypothesis that elevated oxidative status is associated with colorectal adenomatous polyp occurrence during a 10-year period of follow-up.
oxidative stress; biomarkers; F2-isoprostanes; adenomatous polyps; adenoma; colorectal cancer; epidemiology
In a prospective prenatal cohort study, we examined associations of second trimester and cord plasma 25-hydroxyvitamin D (25[OH]D) with small-for-gestational age (SGA), and the extent to which vitamin D might explain black/white differences in SGA.
We studied 1067 white and 236 black mother-infant pairs recruited from 8 obstetrical offices early in pregnancy in Massachusetts. We analyzed 25(OH)D levels using an immunoassay and performed multivariable logistic models to estimate the odds of SGA by category of 25(OH)D level.
Mean (standard deviation [SD]) second trimester 25(OH)D level was 60 nmol/L (21) and was lower for black (46 nmol/L ) than white (62 nmol/L ) women. 59 infants were SGA (4.5%) and more black than white infants were SGA (8.5% vs. 3.7%). The odds of SGA were higher with maternal 25(OH)D levels <25 vs. ≥25 nmol/L (adjusted odds ratio [OR] 3.17; 95% confidence interval [CI]:1.16, 8.63). The increased odds of SGA among black vs. white participants decreased from an OR of 2.04(1.04, 4.04) to 1.68(0.82, 3.46) after adjusting for 25(OH)D.
Second trimester 25(OH)D levels <25 nmol/L were associated with higher odds of SGA. Our data raise the possibility that Vitamin D status may contribute to racial disparities in SGA.
Vitamin D; Infant; Small for Gestational Age; African Continental Ancestry Group; Health Status Disparities; Pregnancy
We hypothesize that lower street connectivity increases the risk of incident lower-body functional limitations (LBFL) among urban African Americans aged 49–65 years.
This population-based cohort was interviewed in-home. Five items measuring LBFL were obtained at baseline and after 3 years. Participants were considered to have LBFL if they reported difficulty on at least 2 of the 5 tasks. Census-tract street connectivity was measured as the ratio of the number of street intersections to the maximum possible number of intersections.
Of 563 subjects with zero or one LBFL at baseline, 109 (19.4 %) experienced two or more LBFL at the 3-year follow-up. Adjusted logistic regression showed that persons who lived in census tracts with the lowest quartile of street connectivity were 3.45 times (95% confidence interval: 1.21 – 9.78) more likely to develop two or more LBFL than those who lived in census tracts with the highest quartile of street connectivity independent of other important environmental factors.
Areas with low street connectivity appear to be an independent contributor to the risk of incident LBFL in middle-aged African Americans.
Disparity; Built environment; Disability; Neighborhood
Intimate partner violence, a prevalent stressor for women, may influence cardiovascular disease risk. We estimated the association between intimate partner violence and development of hypertension, an important risk factor for cardiovascular disease, using data on intimate partner violence in the Nurses’ Health Study II cohort.
Intimate partner violence measures included adult lifetime physical and sexual partner violence and the Women’s Experiences with Battering Scale, which ascertained women’s subjective experience of recent emotional abuse. Physician-diagnosed hypertension was self-reported on biennial questionnaires. We used Cox proportional hazards models to estimate the association between report of intimate partner violence in 2001 and incidence of hypertension from 2001 through 2007.
Of 51,434 included respondents, 22% reported being physically hurt and 10% reported being forced into sexual activities at some point in adulthood by an intimate partner. After adjustment for confounders, physical and sexual abuse were not associated with hypertension. However, women reporting the most severe emotional abuse had a 24% increased rate of hypertension (hazard ratio=1.24; 95% confidence interval: 1.02, 1.53) when compared to women unexposed to emotional abuse.
Hypertension risk appears to be elevated in the small number of women recently exposed to severe emotional abuse.
Domestic violence; spouse abuse; battered women; cardiovascular diseases; hypertension
Epidemiologists have long contributed to policy efforts to address health disparities. Three examples illustrate how epidemiologists have addressed health disparities in the U.S. and abroad through a “social determinants of health” lens.
To identify examples of how epidemiologic research has been applied to reduce health disparities, we queried epidemiologists engaged in disparities research in the U.S., Canada, and New Zealand, and drew upon the scientific literature.
Resulting examples covered a wide range of topic areas. Three areas selected for their contributions to policy were: 1) epidemiology's role in definition and measurement, 2) the study of housing and asthma, and 3) the study of food policy strategies to reduce health disparities. While epidemiologic research has done much to define and quantify health inequalities, it has generally been less successful at producing evidence that would identify targets for health equity intervention. Epidemiologists have a role to play in measurement and basic surveillance, etiologic research, intervention research, and evaluation research. However, our training and funding sources generally place greatest emphasis on surveillance and etiologic research. Conclusions: The complexity of health disparities requires better training for epidemiologists to effectively work in multidisciplinary teams. Together we can evaluate contextual and multilevel contributions to disease and study intervention programs in order to gain better insights into evidenced-based health equity strategies.
Health Status Disparities; Healthcare Disparities; Minority Health; Epidemiology; Policy; Socioeconomic Factors
Childhood obesity is a serious public health problem, resulting from energy imbalance (when the intake of energy is greater than the amount of energy expended through physical activity). Numerous health authorities have identified policy interventions as promising strategies for creating population-wide improvements in physical activity. This case study focuses on energy expenditure through physical activity (with a particular emphasis on school-based physical education [PE]). Policy-relevant evidence for promoting physical activity in youth may take numerous forms including epidemiologic data and other supporting evidence (e.g., qualitative data). The implementation and evaluation of school PE interventions leads to a set of lessons related to epidemiology and evidence-based policy. These include the need to: 1) enhance the focus on external validity, 2) develop more policy-relevant evidence based on “natural experiments,” 3) understand that policymaking is political, 4) better articulate the factors that influence policy dissemination, 5) understand the real world constraints when implementing policy in school environments, and 6) build transdisciplinary teams for policy progress. The issues described in this case study provide leverage points for practitioners, policy makers, and researchers as they seek to translate epidemiology to policy.
Anecdotal evidence suggests that patient compliance with colonoscopy is poorer with Monday procedures and better during winter months since “there is not much else to do”. We examined patients’ compliance to scheduled out-patient endoscopy by time of the day, days of the week and seasons of the year.
We included 2,873 patients who were scheduled for endoscopy from September 2009 to August 2010. Compliant patients were those who showed up for their procedures while non-compliant patients were those who did not show up, without canceling or rescheduling their procedures up to 24 hours prior to their scheduled procedures. We used logistic regression models to evaluate the association between the timing of the scheduled procedure and compliance.
574 (20%) patients did not show up. There was no difference in compliance by time of day of the procedures. However, when compared with patients scheduled for procedures on Monday, there was a trend towards improved adherence as the week progressed, becoming significant on Friday (OR=1.46; 95%CI: 1.06–2.00). There was also better compliance in the warmer months.
Non-compliance with out-patient endoscopy is substantial among underserved populations with limited predictive pattern of compliance by the timing of the procedures.
Endoscopy; colonoscopy; adherence; cancer disparities; epidemiology
We assessed the impact of wasting on survival in tuberculosis patients using precise height-normalized lean tissue mass index (LMI) estimated by bioelectrical impedance analysis and body mass index (BMI).
In a retrospective cohort study, 747 adult pulmonary tuberculosis patients who were screened for HIV and nutritional status were followed for survival.
Of 747 patients, 310 had baseline wasting by BMI (kg/m2) and 103 by LMI (kg/m2). Total deaths were 105. Among men with reduced BMI, risk of death was 70% higher (hazard ratio (HR) = 1.7, 95% CI 1.03, 2.81) than in men with normal BMI. Survival did not differ by LMI among men (HR = 1.1; 95% CI: 0.5, 2.9). In women, both the BMI and LMI were associated with survival. Among women with reduced BMI, risk of death was 80% higher (HR = 1.8; 95% CI: 0.9, 3.5) than in women with normal BMI; risk of death was 5-fold higher (HR = 5.0; 95% CI: 1.6, 15.9) for women with low LMI compared to women with normal LMI.
Wasting assessed by reduced BMI is associated with an increased risk for death among both men and women whereas reduced LMI is among women with tuberculosis.
Tuberculosis; survival; wasting; lean tissue mass index; body mass index; bioelectrical impedance analysis
Increasing evidence suggests that altered immunity and chronic inflammation play a key role in the etiology of many malignancies, but the underlying biological mechanisms involved remain unclear. Systemic markers of immunity may not represent the clinically relevant, site-specific immune response, whereas tissue-based markers may more accurately reflect the local immunologic mechanisms by which precursor lesions develop into cancer. Tissues are often only available in individuals with disease. Previous studies have measured tumor-infiltrating lymphocytes to predict prognosis and survival, but it can be challenging to use tissue-based markers to study the natural history of cancer due to limitations with regard to temporality, the availability of appropriate comparison groups, and other epidemiologic issues. In this commentary, we discuss several epidemiologic study design and study population considerations to address these issues, including the strengths and limitations of using tissue-based markers to study immune response and cancer development. We also discuss how the use of tissue-based immune markers fits into the greater context of molecular epidemiology, which encompasses multiple technologies and techniques, and how implementation of tissue-based immune markers will provide an increased understanding of site-specific biological mechanisms involved in carcinogenesis.
This focus group study describes motivators and barriers to participation in the Mayo Mammography Health Study (MMHS), a large-scale longitudinal study examining the causal association of breast density with breast cancer, involving completion of a survey, providing access to a residual blood sample for genetic analyses, and sharing their results from a screening mammogram. These women would then be followed long-term for breast cancer incidence and mortality.
48 Women participated in six focus groups, four with MMHS non-respondents (N=27), and two with MMHS respondents (N=21). Major themes were summarized using content analysis. Social Cognitive Theory (SCT) was used as a framework for interpretation of the findings.
Barriers to participation among MMHS non-respondents were: 1) lack of confidence in their ability to fill out the survey accurately (self-efficacy); 2) lack of perceived personal connection to the study or value of participation (expectancies); and 3) fear related to some questions about perceived cancer risk and worry/concern (emotional coping responses). Among MMHS respondents, personal experience with cancer was reported as a primary motivator for participation (expectancies).
Application of a theoretical model such as SCT to the development of a study recruitment plan could be used to improve rates of study participation and provide a reproducible and evolvable strategy.
Focus groups; participation; epidemiology; recruitment; social cognitive theory; breast cancer; mammography; qualitative
HIV/AIDS surveillance data are critical for monitoring epidemic trends, but can mask dynamic sub-epidemics, especially in vulnerable populations that under-utilize HIV testing. In this case study, we describe community-based epidemiologic data among injection drug users (IDU) and female sex workers (FSWs) in two northern Mexico-US Border States that identified an emerging HIV epidemic and generated a policy response.
We draw from quantitative and qualitative cross-sectional and prospective epidemiologic studies and behavioral intervention studies among IDUs and FSWs in Tijuana, Baja California and Ciudad Juarez, Chihuahua.
Recognition that the HIV epidemic on Mexico’s northern border was already well established in subgroups where it had been presumed to be insignificant was met with calls for action and enhanced prevention efforts from researchers, NGOs and policy makers.
Successful policies and program outcomes included expansion of needle exchange programs, a nation-wide mobile HIV prevention program targeting marginalized populations, a successful funding bid from the Global Fund for HIV, TB and Malaria to scale up targeted HIV prevention programs and the establishment of binational training programs on prevention of HIV and substance use. We discuss how epidemiologic data informed HIV prevention policies and suggest how other countries may learn from Mexico’s experience.
HIV; AIDS; surveillance; policy; Mexico; US border; epidemiology; injection drug use; sex work
We tested whether experiencing the stressful event of a home mortgage foreclosure was associated with depressive symptomatology.
Data derive from a cohort study of 662 new mothers in the Life-course Influences on Fetal Environment (LIFE) Study. Eligibility included age 18-45 Black/African American mothers who had just given birth to a singleton baby. Mothers enrolled June 2009 to December 2010 were interviewed immediately after giving birth. Our outcome measure was depressive symptoms based on the Center for Epidemiologic Studies-Depression Scale, dichotomized to measure severe depressive symptomatology during the week prior to the interview.
8% of the sample experienced foreclosure in the past 2 years. Covariate-adjusted Poisson regression models showed that women experiencing a recent foreclosure had 1.76 times higher risk for severe depressive symptoms during the week prior to birth compared to women not experiencing foreclosure (95%CI: 1.25 to 2.47, p=.001); foreclosure was also associated with higher excess absolute risk for depressive symptoms (adjusted risk difference =0.173, 95%CI: 0.044 to 0.301, p=.008).
Women who have recently experienced foreclosure are at risk for severe depressive symptoms. The mental health needs of pregnant women experiencing foreclosure or other housing stressors should be considered in clinical practice.
housing; depressive symptoms; childbirth