Regular alcohol drinkng is a determinant of masked morning hypertension detected by home blood pressure monitoring in medicated hypertensive patients with well-controlled clinic blood pressure: The Jichi Morning Hypertension Research (J-MORE) study

Morning blood pressure (BP) level may play an important role in the pathogenesis of cardiovascular events; however, morning BP detected by home BP monitoring may remain uncontrolled in medicated hypertensive patients even when clinic BP is well controlled (masked morning hypertension: MMHT). We studied the determinants of MMHT in stably medicated hypertensive outpatients. In the Jichi Morning Hypertension Research (J-MORE) study, 969 consecutive hypertensive outpatients were recruited by 43 doctors in 32 different institutes. They had been under stable antihypertensive medication status at least for 3 months. Clinic BP was measured on 2 different days and self-measured BP monitoring was conducted twice consecutively in the morning and evening for 3 days. Four-hundred and five patients had well-controlled clinic BP (systolic BP [SBP]<140 mmHg and diastolic BP [DBP]<90 mmHg). Among them, 246 patients (60.7%) had MMHT (morning SBP≥135 mmHg and/or DBP≥85 mmHg). Compared with the patients with normal clinic BP and morning BP, the patients with MMHT had a significantly higher prevalence of regular alcohol drinkers (35.0% vs. 23.3%, p=0.012), a significantly higher number of antihypertensive drug classes (1.83±0.82 vs. 1.66±0.84, p=0.04) and a significantly higher clinic BP level (SBP: 130.4±7.6 mmHg vs. 127.8±8.4 mmHg, p=0.001; DBP: 75.5±7.6 mmHg vs. 73.6±7.6 mmHg, p=0.013). In logistic regression analysis, independent determinants for MMHT were regular alcohol drinking (odds ratio [OR]: 1.76; 95% confidence interval [CI]: 0.99-3.12; p=0.05) and higher-normal clinic BP (130/85 mmHg<clinic SBP/DBP<140/90 mmHg) (OR: 1.60; 95% CI: 1.05-2.44; p=0.03) after adjustment for confounding factors. The patients who both drank alcohol regularly and had a higher-normal clinic BP had 2.71 times higher risk for MMHT than those who did not drink alcohol regularly and had a relatively lower-normal clinic BP (<130/85 mmHg) (p<0.01). In conclusion, regular alcohol drinking is an independent determinant for MMHT detected by home BP monitoring in medicated hypertensive patients with well-controlled clinic BP.