Middle-aged African Americans Research Articles

Weight change among self-reported dieters and non-dieters in white and African American men and women.

Few studies have examined the association between dieting and weight change in general population and results have been inconsistent. To the best of our knowledge, no such study has been done in middle-aged African Americans. We examined 10,554 white and African American men and women who were participants in the Atherosclerosis Risk in Communities (ARIC) Study and attended examinations between 1986 and 1994. We found that the prevalence of dieting in white women, white men, African American women, and African American men was 6.5, 2.3, 3.5, and 0.9%, respectively. After controlling for the covariates, the difference in the mean annual weight gain between dieters and nondieters was 0.61, 0.46, and 0.59 kg/year among white women, white men, and African American women, respectively. In conclusion, in this cohort of white men and women and African American women aged 45-64 years, self-reported dieting was associated with a larger mean annual weight gain than non-dieting over a period of 6 years.

Incident type 2 diabetes mellitus in African American and white adults: the Atherosclerosis Risk in Communities Study.

Although the excess prevalence of type 2 diabetes mellitus in African Americans is well established, few studies have compared incident diabetes in African American and white persons. To compare risk of incident diabetes in African American vs white adults and to identify explanatory factors for racial disparities. Prospective cohort study using baseline data collected from 1986 to 1989 from the ongoing Atherosclerosis Risk in Communities (ARIC) Study, with 9 years of follow-up. A total of 2646 African American and 9461 white adults aged 45 to 64 years without diabetes at baseline, sampled from 4 US communities. Incident type 2 diabetes, ascertained by self-report of physician diagnosis, use of diabetes medications, or fasting glucose level of at least 7.0 mmol/L (126 mg/dL), compared among white and African American subjects and by presence of potentially modifiable risk factors. Diabetes incidence per 1000 person-years was about 2.4-fold greater in African American women (25.1 [95% confidence interval [CI], 22.4-28.1] vs 10.4 [95% CI, 9.4-11.4]) and about 1.5-fold greater in men (23.4 [95% CI, 19.9-27.2] vs 15.9 [95% CI, 14.6-17.2]) than in their white counterparts (P<.001). Results from proportional hazards regression models indicated that racial differences in potentially modifiable risk factors, particularly adiposity, accounted for 47.8% of the excess risk in African American women but accounted for little excess risk in African American men. Compared with their white counterparts, African American men and women had higher blood pressures before diabetes onset (diastolic blood pressure difference=5.6 mm Hg in women and 8.4 mm Hg in men; P=.005). Our data indicate that compared with their white counterparts, middle-aged African Americans are at greater risk of developing type 2 diabetes and have higher blood pressure prior to development of diabetes. In women, almost 50% of this excess risk might be related to potentially modifiable factors.

Social heterogeneity in smoking among African Americans.

This study assessed the effects of sociodemographic variables on the smoking behavior of African Americans. Data for 14,397 African-American respondents (18-64 years old) to the National Health Interview Survey in the years 1990 through 1993 were examined in multivariate models. Age was the strongest predictor of smoking, and men were at least 1.75 times as likely as women to be smokers (P < .001). The Year 2000 goal of an 18% prevalence rate among African-American adults may not be attained without major community interventions focusing on male and middle-aged African Americans.

Seven-year incidence of hypertension in a cohort of middle-aged African Americans and whites.

Many studies have suggested that African Americans have a higher prevalence of hypertension than whites. The authors conducted a prospective study of hypertension incidence from 1987-1988 to 1994-1995 in 140 African American and 237 white adults aged 30 to 54 years at baseline. The study participants were screened for participation in the Trials of Hypertension Prevention, phase 1, an 18-month lifestyle modification intervention trial aimed at lowering blood pressure, at the Baltimore Clinical Center. Baseline age, blood pressure, body mass index, and heart rate were similar in the two groups. Compared with whites, however, African Americans had a lower percentage of men, college graduates, and households with an income > or = $40,000 per year. African Americans also had lower mean urinary sodium to creatinine ratio and potassium to creatinine ratio, but a similar sodium to potassium ratio. The incidence of hypertension (blood pressure > or = 160/95 mm Hg and/or taking antihypertensive medication) over 7 years of follow-up was nearly identical: 25.7% in African Americans and 25.3% in whites. Baseline age, gender, blood pressure, and heart rate were all associated with the incidence of hypertension. Even after adjustment for these covariables, the risk of hypertension was not higher in African Americans compared with whites. These results indicate that middle-aged African Americans and whites have a similar risk of developing hypertension given the same age, initial blood pressure, and body mass index at baseline.

RELATIONSHIPS BETWEEN BLOOD PRESSURE AND DIETARY NUTRIENTS IN AFRICAN-AMERICAN AND CAUCASIAN FEMALES

343 Incidence of hypertension in African-Americans (AA) is nearly double that in Caucasians (CAU). The effect of dietary nutrients on blood pressure (BP) in either/both races is unclear. The purpose of this study was to determine the relationship between BP and dietary nutrients in normotensive, middle-aged AA and CAU females. Resting systolic (SBP), diastolic (DBP) and mean arterial pressure (MAP) were measured in 15 AA females (38.9 yr.; wt. 71.2 kg, 37.5%fat) and in 21 CAU females (42 yr.; wt. 62.0 kg; 31%fat). Three-day diet records were used to determine daily nutrient intakes. T-tests were used to determine differences in variables between the races. Pearson correlations were used to determine the relationships between BP and dietary variables for all subjects and within races. BP measures did not statistically differ between the races, however SBP and MAP were physiologically higher (≥ 5 mmHG) in the AA females. Nutrient intakes did not differ between the races except for K+ and Ca++ which were higher (p<0.05) in the Caucasians. SBP, DBP and MAP were positiviely correlated (r≥0.45; p≤0.05) with fat(g),%dietary fat and negatively correlated (r≤-0.5;p≤0.02) with%CHO in the CAU females and similarly in all 36 subjects. However, no such correlations were observed in the AA females. These data indicate that the relationship between BP and intakes of fat and CHO differ between normotensive AA and CAU females. Thus, future research should consider race as a factor in designing dietary interventions to address BP.

Development of the multiple metabolic syndrome in the ARIC cohort: Joint contribution of insulin, BMI, and WHR

PURPOSE: The natural history of the multiple metabolic syndrome (MMS) and its predictors has rarely been addressed in population samples. This study evaluated the predictive role of fasting serum insulin, body mass index (BMI), and waist-to-hip ratio (WHR) on the development of incident MMS components (diabetes, hypertension, and dyslipidemias) over the course of three years. METHODS: The study population comprised the cohort of middle-aged African American and European American men and women of the Atherosclerosis Risk in Communities Study (1987–1992), RESULTS: Among 6113 individuals free of MMS components at baseline, high insulin (> 14 μU/ ml) was independently predictive of the development of one or more MMS components (OR: 1.5, 95% CI: 1.2–1.8), as was a BMI ⩾ 30 (OR:1.7, 95% CI:1.4–2.0), and a high WHR (> 0.98) (OR:1.5, 95% CI: 1.3–1.8) adjusting statistically for age, gender, and ethnicity/center. These associations were markedly stronger for combinations of MMS components (two or more) than for isolated components. CONCLUSIONS: The findings confirm earlier reports on the predictive role of insulin, BMI, and WHR, and suggest that these antecedent factors may be integral to the development of combinations of disorders, i.e., the particular clustering identified as the MMS.

Can We Prevent End-Stage Renal Disease due to Hypertension or to Diabetes Mellitus?

In the United States, there are about 200 000 patients with end-stage renal disease (ESRD) who either are being treated by long-term dialysis or have a functioning kidney transplant. Over 40 000 new patients need to start such renal replacement therapy each year. Two thirds of this ESRD is now due to two treatable systemic diseases. Because it is more common, type II diabetes mellitus causes more ESRD than type I, and causes it in older patients. The other main cause, hypertensive nephrosclerosis, causes ESRD mainly in older whites, whereas it is an important cause of ESRD in young adult and middle-aged African Americans. See also pp 3079 and 3085. The prevalence of ESRD is significantly higher in African Americans for all causes except congenital ones such as polycystic disease.1-3The black:white ratio for ESRD due to hypertensive nephrosclerosis approaches 20:1 in the age group 25 to 45 years.