SYSTOLIC BLOOD-PRESSURE TRENDS IN US ADULTS BETWEEN 1960 AND 1980 - INFLUENCE OF ANTIHYPERTENSIVE DRUG-THERAPY

Recent blood pressure trends reflect progress in hypertension control, but prevalent drug therapy precludes direct estimation of the compone nt due to primary prevention. In data gathered on persons aged 35-74 y ears in three successive US health examination surveys (1960-1980), sy stolic blood pressure levels assuming no drug therapy were imputed by reassigning blood pressure to the upper end of the distribution for re spondents reporting use of antihypertensive medication. Blood pressure was partitioned into four ordinal categories based on weighted percen tiles of the 1960-1962 distributions for 35- to 44-year-old males and females who reported no use of antihypertensive medication. Cumulative legit models (alpha = 0.01) were used to estimate age- and sex-specif ic trends for blacks and whites within two strata (<25 or greater than or equal to 25) of body mass index (BMI) (weight (kg)/height (m)(2)). Before imputation, systolic blood pressure decreased between 1960 and 1980; after imputation, significant decreases remained only in 35- to 44-year-olds. Strong associations of black race and BMI greater than or equal to 25 with higher blood pressures were present in models with and without drug therapy. Thus, according to the models, there has be en little progress in decreasing racial or BMI-related blood pressure differentials, Above the age of 44 years, blood pressure trends were l argely attributable to medication use. In contrast, data for 35- to 44 -year-olds suggest progress in primary prevention.