Jennifer Madans

Are Racial and Ethnic Minorities Less Willing to Participate in Health Research

Background It is widely claimed that racial and ethnic minorities, especially in the US, are less willing than non-minority individuals to participate in health research. Yet, there is a paucity of empirical data to substantiate this claim. Methods and Findings We performed a comprehensive literature search to identify all published health research studies that report consent rates by race or ethnicity. We found 20 health research studies that reported consent rates by race or ethnicity. These 20 studies reported the enrollment decisions of over 70,000 individuals for a broad range of research, from interviews to drug treatment to surgical trials. Eighteen of the twenty studies were single-site studies conducted exclusively in the US or multi-site studies where the majority of sites (i.e., at least 2/3) were in the US. Of the remaining two studies, the Concorde study was conducted at 74 sites in the United Kingdom, Ireland, and France, while the Delta study was conducted at 152 sites in Europe and 23 sites in Australia and New Zealand. For the three interview or non-intervention studies, African-Americans had a nonsignificantly lower overall consent rate than non-Hispanic whites (82.2% versus 83.5%; odds ratio [OR] = 0.92; 95% confidence interval [CI] 0.84–1.02). For these same three studies, Hispanics had a nonsignificantly higher overall consent rate than non-Hispanic whites (86.1% versus 83.5%; OR = 1.37; 95% CI 0.94–1.98). For the ten clinical intervention studies, African-Americans overall consent rate was nonsignificantly higher than that of non-Hispanic whites (45.3% versus 41.8%; OR = 1.06; 95% CI 0.78–1.45). For these same ten studies, Hispanics had a statistically significant higher overall consent rate than non-Hispanic whites (55.9% versus 41.8%; OR = 1.33; 95% CI 1.08–1.65). For the seven surgery trials, which report all minority groups together, minorities as a group had a nonsignificantly higher overall consent rate than non-Hispanic whites (65.8% versus 47.8%; OR = 1.26; 95% CI 0.89–1.77). Given the preponderance of US sites, the vast majority of these individuals from minority groups were African-Americans or Hispanics from the US. Conclusions We found very small differences in the willingness of minorities, most of whom were African-Americans and Hispanics in the US, to participate in health research compared to non-Hispanic whites. These findings, based on the research enrollment decisions of over 70,000 individuals, the vast majority from the US, suggest that racial and ethnic minorities in the US are as willing as non-Hispanic whites to participate in health research. Hence, efforts to increase minority participation in health research should focus on ensuring access to health research for all groups, rather than changing minority attitudes.

Risk Factors for Hip Fracture in White Men: The NHANES I Epidemiologic Follow‐up Study

This prospective population‐based study assessed predictors of hip fracture risk in white men. Participants were members of the Epidemiologic Follow‐up Study cohort of the First National Health and Nutrition Examination Survey, a nationally representative sample of noninstitutionalized civilians who were followed for a maximum of 22 years. A cohort of 2879 white men (2249 in the nutrition and weight‐loss subsample, 1437 in the bone density subsample) aged 45–74 years at baseline (1971–1975) were observed through 1992. Ninety‐four percent of the original cohort were successfully traced. Hospital records and death certificates were used to identify a total of 71 hip fracture cases (61 in the nutrition and weight‐loss subsample, 26 in the bone‐density subsample). Among the factors evaluated were age at baseline, previous fractures other than hip, body mass index, smoking status, alcohol consumption, nonrecreational physical activity, weight loss from maximum, calcium intake, number of calories, protein consumption, chronic disease prevalence, and phalangeal bone density. The risk adjusted relative risk (RR) of hip fracture was significantly associated with presence of one or more chronic conditions (RR = 1.91, 95% confidence interval [CI] = 1.19–3.06), weight loss from maximum ≥ 10% (RR = 2.27, 95% CI 1.13–4.59), and 1 SD change in phalangeal bone density (RR = 1.73, 95% CI 1.11–2.68). No other variables were significantly related to hip fracture risk. Although based on a small number of cases, this is one of the first prospective studies to relate weight loss and bone density to hip fracture risk in men.

Diabetes mellitus, coronary heart disease incidence, and death from all causes in African American and European American women: The NHANES I epidemiologic follow-up study.

Few data are available on risk for coronary heart disease in African American women with diabetes mellitus, a well-established coronary risk factor in European American women. This study tests the hypothesis that medical history of diabetes predicts coronary heart disease incidence in African American women in a national cohort. Participants in the NHANES I Epidemiologic Follow-up Study in this analysis were 1035 African American and 5732 European American women aged 25-74 years without a history of coronary heart disease. Average follow-up for survivors was 19 years (maximum 22 years). Risk of incident coronary heart disease by baseline diabetes status was estimated. Proportional hazards analyses for African American women aged 25-74 revealed significant associations of coronary heart disease risk with diabetes after adjusting for age (RR = 2.40; 95% CI, 1.58-3.64, P < 0.01). After adjusting for age, smoking, and low education, there was an elevated risk in diabetics age 25-74 (RR = 2. 34; 95% CI, 1.54-3.56, P < 0.01); this association did not differ significantly from that for European American women. Excess coronary incidence in African American compared to European American women aged 25-64 was statistically explained by controlling for diabetes history, age, education, and smoking but only partly explained by age and diabetes history. In African American women aged 25-74, diabetes was also associated with increased coronary heart disease, cardiovascular, and all-cause mortality. The population attributable risk of coronary heart disease incidence associated with a medical history of diabetes was 8.7% in African American women and 6.1% in European American women. Medical history of diabetes was a significant predictor of coronary heart disease incidence and mortality in African American women and explained some of the excess coronary incidence in younger African American compared to European American women.

Body fat distribution and hypertension incidence in women and men. The NHANES I Epidemiologic Follow-up Study

OBJECTIVE: To test the hypothesis that an elevated ratio of subscapular to triceps skinfold thickness (SFR), one measure of truncal obesity, is associated with increased incidence of essential hypertension.DESIGN: Data from the NHANES I Epidemiologic Follow-up Study (NHEFS) were analyzed.SUBJECTS: A cohort of 4303 women and 2579 men with complete data who were normotensive at baseline in 1971–1975.MEASUREMENTS: Incidence of hypertension, blood pressure 160/95u2005mmu2005Hg or greater or on blood pressure medication at follow-up in 1982–1984.RESULTS: There was a statistically significant increase in risk of hypertension over approximately 10u2005y follow-up in white women aged 25–74u2005y with SFR in the fifth compared to the first quintile independent of age and body mass index (BMI) (relative risk=1.52, 95% confidence interval 1.13–2.06, P=0.006). The association was somewhat diminished after controlling for baseline blood pressure, change in BMI and other risk variables. An even stronger association was seen for subscapular skinfold and hypertension incidence. In white men aged 25–74u2005y, a significant association of high SFR with age-, BMI-adjusted risk of hypertension was seen (RR=1.41, 95% CI 1.01–1.96, P=0.04). Data for black women or black men failed to reveal significant variation in hypertension risk among quintiles of SFR or subscapular skinfold except in black women with low baseline BMI.CONCLUSIONS: Data from NHEFS confirm the association of higher truncal obesity with increased incidence of hypertension in white women. Further studies are needed, especially in larger samples of black women.

The relation between fish consumption, death from all causes, and incidence of coronary heart disease: the NHANES I Epidemiologic Follow-up Study

1 time/week (adjusted relative risk 0.85, 95% CI 0.68-1.06). Similar but nonsignificant trends were seen in white and black women, but not black men. In white men, risk of noncardiovascular death but not cardiovascular death was also significantly reduced in those consuming fish once or more a week. No consistent association of fish consumption and coronary heart disease incidence or mortality was seen. White men consuming fish once a week had significantly lower risk of death over a 22-year follow-up than those never consuming fish. This was mostly attributable to reductions in death from noncardiovascular causes. Similar patterns, though not significant, were seen in women. Further studies are needed to confirm these findings and to elucidate mechanisms for the effect of fish consumption on noncardiovascular mortality.

Bone mineral density and mortality in women and men: the NHANES I epidemiologic follow-up study.

PURPOSEnWe sought to assess the long-term association of bone mineral density with total, cardiovascular, and non-cardiovascular mortality.nnnMETHODSnThe First National Health and Nutrition Examination Survey data were obtained from a nationally representative sample of non-institutionalized civilians. A cohort aged 45 through 74 years at baseline (1971-1975) was observed through 1992. Subjects were followed for a maximum of 22 years. Included in the analyses were 3501 white and black subjects. Death certificates were used to identify a total of 1530 deaths.nnnRESULTSnResults were evaluated to determine the relative risk for death per 1 SD lower bone mineral density, after controlling for age at baseline, smoking status, alcohol consumption, history of diabetes, history of heart disease, education, body mass index, recreational physical activity, and blood pressure medication. Bone mineral density showed a significant inverse relationship to mortality in white men and blacks, but did not reach significance in white women. Based on 1 SD lower bone mineral density, the relative risk for white men was 1.16 (95% confidence interval (CI), 1.07-1.26, p<.01), while for white women the relative risk was 1.10 (95% CI, 0.99-1.23, p=.07), and in blacks the relative risk was 1.22 (95% CI, 1.05-1.42, p<.01). Bone mineral density was also associated with non-cardiovascular mortality in all three race-gender groups. An association between bone mineral density and cardiovascular mortality was found only in white men.nnnCONCLUSIONSnBone mineral density is a significant predictor of death from all causes (white men, blacks), cardiovascular (white men only) and other causes combined, in whites and blacks.

Body fat distribution, obesity, overweight and stroke incidence in women and men--the NHANES I Epidemiologic Follow-up Study.

OBJECTIVE: To test the hypothesis that an elevated ratio of subscapular to triceps skinfold thickness (SFR), a measure of truncal obesity, is associated with increased incidence of stroke independent of overweight.DESIGN: Data from the NHANES I Epidemiologic Follow-up Study were analyzed.SUBJECTS: A cohort of 3652 women and 3284 men with complete data who had no history of stroke at baseline in 1971–1975.MEASUREMENTS: Incidence of stroke diagnosed at hospital discharge or death during the follow-up period through 1992; triceps and subscapular skinfold thickness (SSF) and body mass index (BMI) at baseline.RESULTS: In a complex relationship, higher SFR was associated with a mildly but significantly increased incidence of stroke only in white male former smokers. In white men, SSF showed a U-shaped association with stroke risk. In white men, stroke risk was elevated in the top quartile of BMI only in never smokers. In black women, stroke risk was significantly elevated in the bottom compared to the top quartile of BMI. No significant associations were seen in white women or black men.CONCLUSIONS: In white men, SSF showed a U-shaped association with stroke risk, which was elevated in the top quartile of BMI only in never smokers. Surprisingly, stroke risk was elevated in black women with the lowest BMI. More studies of these associations are needed, especially in black women.

Bone Mineral Density and Stroke

Background and Purpose— We sought to assess the long-term predictive usefulness of bone mineral density (BMD) for stroke incidence and stroke mortality. Methods— The First National Health and Nutrition Examination Survey data were obtained from a nationally representative sample of noninstitutionalized civilians. A cohort of 3402 white and black subjects 45 through 74 years of age at baseline (1971 to 1975) was observed through 1992. Hospital records and death certificates were used to identify a total of 416 new stroke cases. Results— Results were evaluated to determine the relative risk (RR) for stroke per 1-SD decrease in BMD, after controlling for age at baseline, smoking status, alcohol consumption, history of diabetes, history of heart disease, education, body mass index, recreational physical activity, and blood pressure medication. In Cox proportional-hazards analyses, incidence of stroke was not associated with a decrease in BMD in any of the 3 race-sex groups: white men (RR, 1.01; 95% CI, 0.86 to 1.19;P =0.88), white women (RR, 1.13; 95% CI, 0.93 to 1.38;P =0.21), or blacks (RR, 0.93; 95% CI, 0.72 to 1.21;P =0.60). No association between BMD and stroke mortality was found (RR, 1.03; 95% CI, 0.86 to 1.23;P =0.77). Conclusions— In a large national study, no significant associations of BMD and stroke incidence or mortality were found for whites or blacks.

REGIONAL VARIATION IN ISCHEMIC HEART DISEASE INCIDENCE

This study examines the relationship between cardiovascular risk factors and regional variation in IHD incidence among white males 55-74 years of age from the NHANES I Epidemiologic Followup Study. The age-adjusted IHD incidence rate was lowest in the west (31.3 per 1000 persons years of followup). The rates in the northeast, midwest, and south were similar and so they were combined into one region, the non-west, with a rate of 42.4. Differences in risk factors (smoking, educational level, hypertension, serum cholesterol, diabetes mellitus, and body mass index) did not explain the regional differences in IHD incidence. After adjusting for baseline risk factors using proportional hazards model, the risk of IHD incidence was still 38% higher in the non-west compared to the west. However, the effect of hypertension, diabetes, and body mass index on IHD incidence varied by region.

The development and testing of a module on child functioning for identifying children with disabilities on surveys. I: Background

This is the first of three papers that will document the development of a survey module on child functioning developed by UNICEF in collaboration with the Washington Group on Disability Statistics (WG), and demonstrate - both conceptually and through test results - the strengths of that module compared with alternative tools for identifying children with disabilities in household surveys. This first paper in the series sets the background and reviews the literature leading to the development of the UNICEF/WG Child Functioning Module (CFM) and presents the WG Short Set of questions (WG-SS) and the Ten Question Screening Instrument (TQSI) as precursors, outlining some of their shortcomings and how the UNICEF/WG CFM was designed to meet those challenges. Subsequent articles will summarize results from the cognitive and field testing of the CFM including comparisons with results derived from the TQSI and the WG-SS.