P210 ASSOCIATION BETWEEN FOLLOW-UP BLOOD PRESSURE AND BLOOD PRESSURE CONTROL: A META-REGRESSION ANALYSIS

Abstract

Background: Blood pressure (BP) control is typically defined as BP values under certain thresholds, most commonly <140/90 mmHg – but there is widespread uncertainty about how mean BP is related to BP control, and what mean BP is required to achieve BP control in 80% of patients. Objective: To assess the association between follow-up mean systolic BP (SBP) and BP control from randomised clinical trials (RCTs). Methods: We systematically searched multiple databases for relevant RCTs. We included double-blind individual RCTs (iRCTs) of adults with hypertension, randomised to BP-lowering drugs from five major antihypertensive classes for ≥2 to ≤ 26 weeks, and which reported data for follow-up mean SBP and BP control (clinic BP <140/90 mmHg) at the last follow-up visit. We also included cluster RCTs (cRCTs), of adults with hypertension, randomised to any BP-lowering intervention, for any duration. The association between follow-up mean SBP and BP control at the last follow-up visit was assessed using a linear regression model. The coefficient was interpreted as the increase in percentage of patients with BP control for every 1 mmHg decrease in follow-up mean SBP. Results: Seventy iRCTs (45,836 participants) and 36 cRCTs (28,154 participants) were included. Each 1 mmHg decrease in follow-up mean SBP was associated with about 2% improvement in BP control in both iRCTs and cRCTs (R2= 78% and 76%, respectively). This finding was broadly consistent in the subgroups of BP-lowering drug classes, baseline SBP categories, and pre-trial BP-lowering treatment status in iRCTs, and country income and baseline SBP categories in cRCTs. Mean SBP levels of 125, 130, and 135 mmHg were associated with BP control rates of 78%, 67%, and 55%, respectively, in iRCTs and 80%, 68%, and 56% in cRCTs. Conclusion: Mean SBP levels of 125 mmHg are required for achieving BP control of <140/90 mmHg in about 80% of the patients. These findings should inform clinical care, guideline recommendations and hypertension control programs.