ABSTRACT
OBJECTIVES: To compare, according to blood pressure (BP) categories, 10-year trends in BP measurements in nonhypertensive subjects and the relative risk of developing hypertension. DESIGN: Population study. BP was recorded as the average of two measures taken on a single occasion with a mercury sphygmomanometer and the auscultation method. SETTING: Residents of La Plata, aged 15 to 64 years. PARTICIPANTS: The study was based on randomly chosen individuals who, during a previous survey in 1985, were 15 to 64 years old and whose BP was below 140/90 mmHg. They were grouped according to sex and BP categories. Random age- and sex-stratified sampling of 151 men and 193 women was performed. Categories were high normal BP, optimal BP (as defined by the fifth report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure) and normal but not optimal BP defined as BP 120 to 129/80 to 84 mmHg. RESULTS: BP increased in all categories; this increase was significant (P < 0.01) except for diastolic BP in women with high normal BP. BP increases were higher in optimal BP subjects and lower in high normal BP subjects (P < 0.01 for women and not significant for men). The relative risk of developing hypertension in high normal BP subjects was triple that in optimal BP subjects (P < 0.01). CONCLUSIONS: Increases in BP observed in optimal BP subjects stress the importance of monitoring BP changes and recommending primary prevention in the whole population.
