Effects of gender and ethnic group on blood pressure control in the elderly.

In order to determine the adequacy of blood pressure treatment in black and white elderly men and women, the authors performed a cross-sectional population survey in Central North Carolina in 1986-1987. Participants included a random sample of noninstitutionalized individuals age 65 years or older. Blacks were oversampled. A health questionnaire was administered, and blood pressure was measured. Of 5,223 eligible persons, 4,162 (80%) participated. Fifty-four percent of subjects were black and 65% were women. Sixteen percent of the study subjects were white men, 30% white women, 19% black men, and 35% black women. The mean age was 73 years. Fifty-three percent had hypertension. Among hypertensives, 80.8% were taking blood pressure medication. Among treated hypertensives, blood pressure was adequately controlled, (measured diastolic blood pressure of 90 mm Hg or lower) in 85.6%. Women were 52% more likely than men and blacks were 40% less likely than whites to exhibit adequate blood pressure control. Older age and smoking were also associated with better blood pressure control. The authors conclude that hypertension is more likely to be controlled in elderly women than men and less likely to be well-controlled in elderly blacks than whites. The choice of antihypertensive agent may also be important. Further investigation is needed into the mechanisms accounting for the observed sex and race differences.

Association of hypertension with beta2- and alpha2c10-adrenergic receptor genotype.

The adrenergic receptors have been implicated in the pathogenesis of essential hypertension. We hypothesized that hypertension is associated with variants at the beta2-adrenergic receptor locus and at one of the alpha2-adrenergic receptor loci. In unrelated individuals, we measured untreated blood pressure and characterized each subject as hypertensive or normotensive. We then used genomic DNA to identify beta2- and alpha2c10-adrenergic receptor restriction fragment length polymorphisms. In 175 subjects (49 percent with hypertension, 55 percent black), both hypertension and race were associated with genotype at the beta2 locus (chi2 for hypertension = 11, P = .004, chi2 for race = 8.8, P = .012). The association with hypertension persisted in each race group separately (blacks only: chi2 = 9.6, P = .008; whites only; chi2 = 14.2, P = .001). This association persisted in a logistic model that controlled for race (P = .01). Genotype was also significantly associated with baseline systolic, diastolic, and mean arterial blood pressures (P = .05, .01, and .02, respectively). These data suggest that the beta2-adrenergic receptor gene is a candidate gene for hypertension in blacks and whites. We also genotyped subjects at the alpha2-adrenergic receptor coded on chromosome 10. There was no association between hypertension and genotype at the alpah2c10 locus in the total group or in blacks, but there was significant association in whites (chi2 = 6.7, P = .03). These data suggest that the beta2- and alph2c10-adrenergic receptor genes may contribute, in a race-specific manner, to the inheritance of essential hypertension. Linkage studies in related individuals are needed to confirm these findings.