Sleep-time ambulatory blood pressure as a novel therapeutic target for cardiovascular risk reduction

Diagnosis of hypertension and clinical decisions regarding its treatment are typically based upon daytime clinic blood pressure (BP) measurements, occasionally supplemented by wake-time patient self-assessment. Yet, correlation between BP level and target organ damage, cardiovascular disease (CVD) risk, and long-term prognosis is higher for ambulatory BP monitoring (ABPM) measurements. Numerous studies consistently reveal CVD events are better predicted by the asleep than awake or 24 h BP means. In addition, when the asleep BP mean is adjusted by the awake mean, only the former is a significant independent predictor of outcome. Endogenous circadian rhythms explain statistically and clinically significant ingestion time differences in efficacy, duration of action, safety and/or effects on the daily BP pattern of most hypertension medications and their combinations. Bedtime versus morning-time ingestion of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, independent of drug terminal half-life, both better reduces asleep BP and normalizes the daily BP profile into a more normal dipper pattern. The recently completed prospective outcome MAPEC Study verifies therapeutic restoration of the normal sleep-time BP decline, a novel therapeutic goal most effectively achieved by ingestion of the entire daily dose of ⩾ 1 conventional hypertension medications at bedtime, best decreases CVD morbidity and mortality. Our findings indicate around-the-clock ABPM is a clinical necessity to accurately detect abnormal sleep-time BP and assess CVD risk, and that hypertension ought to be managed by a bedtime therapeutic strategy, preferably one including medication that antagonizes the activities and actions of the renin-angiotensin-aldosterone system.