Background: We aimed to assess blood pressure (BP) parameters during follow-up that can help identify normotensive middle-aged adults with increased risk for the development of subsequent hypertension.
Methods: We studied 7,724 normotensive subjects who were followed-up in a tertiary outpatient clinic. BP values were obtained at each yearly follow-up visit for 3 consecutive years. The following systolic blood pressure (SBP) parameters among the 3 visits were assessed as independent predictors for the development of subsequent hypertension: mean SBP value, baseline (first visit) value, maximum SBP value, and most recent (last visit) SBP value.
Results: Mean age of study subjects was 48.43±9.74 years, and 73% were males. A total 1159 (15%) subjects developed hypertension during a mean follow-up of 65±37.25 months. Multivariate Cox proportional regression analysis, with comparison of model fit, showed that the mean SBP value during the 3 follow-up visits was the most powerful predictor for the development of subsequent hypertension (HR=10% risk increase per each 1 mmHg increment in mean SBP [p<0.001]), whereas single-point assessments, including baseline, maximum, and most recent SBP values, were less strongly associated with the development of subsequent hypertension. Consistently, Kaplan-Meier survival analysis showed that increased tertiles of mean follow-up SBP were significantly associated with corresponding increased rates of subsequent hypertension (Figure).
Conclusion: Long-term assessment of mean blood pressure values during follow-up provides incremental prognostic information for the development of subsequent hypertension to single-point measurements in normotensive middle-aged adults.
