Ambulatory blood pressure pattern in resistant hypertension is markedly affected by the time of antihypertensive treatment

Abstract

Listen

Translate article

Patients with resistant hypertension present high prevalence of a non-dipper blood pressure (BP) pattern (<10% decline in the nocturnal relative to the diurnal BP mean) and an associated elevated cardiovascular risk. Recent results indicate that non-dipping is partly related to the absence of 24h therapeutic coverage in patients treated with single morning doses [J Hypertens. 2002;20:1097–1104]. Accordingly, we studied the impact of the time of treatment on the circadian BP pattern in patients with resistant hypertension. We studied 712 patients with resistant hypertension (367 men), 59.2±11.5 years of age. Among them, 309 patients were receiving all their medication upon awakening, and 403 were taken one antihypertensive drug at bedtime. BP was measured at 20-min intervals from 07:00 to 23:00 hours and at 30-min intervals at night for 48 consecutive hours. Physical activity was simultaneously monitored every minute by wrist actigraphy to accurately calculate the diurnal and nocturnal means of BP on a per subject basis. In comparison with patients who received all their medication upon awakening, subjects with one drug before bedtime were characterized by a significant reduction in the 24h mean of systolic and diastolic BP (3.5 and 2.1 mm Hg, respectively; P<0.010). This reduction was much more prominent during nocturnal resting hours (5.8 and 3.3 mm Hg, P<0.001). Accordingly, the day/night BP ratio (nocturnal decline of BP relative to the diurnal mean) was also significantly increased (by 2.6 and 2.8 for systolic and diastolic BP ratio, P<0.001) in patients taken one drug at bedtime. A very high 79.0% of the patients receiving all drugs on awakening were non-dippers. This prevalence was significantly reduced to 52.6% in patients who received one drug at bedtime (P<0.001). In patients with resistant hypertension, pharmacological therapy should take into account when to treat with respect to the rest-activity cycle of each patient, as a function of the therapeutic coverage of the drugs and the baseline circadian BP profile of each patient. This chronotherapeutic approach allows reducing the prevalence of an altered non-dipper BP profile, associated with an increased cardiovascular risk.