RELATIONSHIP BETWEEN METABOLIC SYNDROME, TIME OF TREATMENT AND BLOOD PRESSURE NON-DIPPING PROFILE IN ESSENTIAL HYPERTENSION: PP.3.112

Abstract

Objectives: There is a strong association between metabolic syndrome (MS) and increased cardiovascular risk. Moreover, non-dipping (<10% sleep-time relative blood pressure (BP) decline) has also been linked to increased cardiovascular morbidity and mortality. Several studies have documented that non-dipping is partly related to the absence of 24 h therapeutic coverage in hypertensive subjects treated with single morning doses. Accordingly, we investigated the association between MS, time of treatment and the circadian BP pattern in essential hypertension. Methods: We studied 3352 non-diabetic treated hypertensive patients (1576 men), 53.7 ± 13.1 years of age. Among them, 2056 were ingesting all their antihypertensive medication upon awakening and 1296 were taken medication at bedtime. BP was measured every 20-min from 07:00 to 23:00 h and every 30-min at night for 48 h. Blood and urine tests were performed within the same week before starting BP monitoring. Results: MS was present in 52.6% of the subjects. The prevalence of a non-dipper BP profile was significantly higher in subjects with MS (52.0 vs. 39.5% in subjects without MS, P < 0.001). Non-dipping was significantly more prevalent among subjects receiving all medication on awakening (56.8%) than among those receiving medication at bedtime (29.1%; P < 0.001 between groups). Subjects with MS had significantly higher uric acid (6.0 vs. 5.3 mg/dl, P < 0.001), fibrinogen (331 vs. 315 mg/dl, P < 0.001), and erythrocyte sedimentation rate (14.8 vs. 12.4 mm, P < 0.001). Non-dipping was significantly associated to the presence of MS and treatment on awakening in a multiple logistic regression model adjusted by other significant confounding factors, including age, serum creatinine, erythrocyte sedimentation rate, and cigarette smoking. The single most relevant factor in the definition of MS associated to non-dipping was diminished HDL-cholesterol. Conclusions: This study documents a significant increase of a blunted nocturnal BP decline in treated hypertensive subjects with MS. Bedtime treatment significantly reduces the prevalence of an altered non-dipper BP profile, associated with an increased cardiovascular risk, while providing higher BP control and improved metabolic profile in essential hypertension.