S-37-3: NIGHTTIME AND DAYTIME HOME BLOOD PRESSURE AND THE CARDIOVASCULAR DISEASE INCIDENCE IN TREATMENT-RESISTANT HYPERTENSION

Abstract

Introduction: Individuals with treatment-resistant hypertension (TRH) often concurrently have obesity, diabetes, or sleep apnea, conditions that confer a high risk of cardiovascular disease (CVD) and are related to nocturnal hypertension. We therefore hypothesized that nighttime home BP may be a superior predictor of CVD events compared to daytime home BP in patients with TRH. Methods: We conducted the present study of 297 patients with TRH, which was defined as uncontrolled office BP (≧140/90 mmHg) with using three classes of medications including diuretics or using ≧4 classes of medications with controlled or uncontrolled BP levels. The patients were among the original 2,545 outpatients in the J-HOP (Japan Morning Surge-Home Blood Pressure) Nocturnal BP study, a nationwide practitioner-based study of nighttime home BP monitoring (HBPM), and underwent consecutive 14-day daytime (morning and evening) HBPM and nighttime HBPM using a device programmed to take nighttime BP measurements at 2:00, 3:00, and 4:00 a.m. (one measurement at each time point, for a total of three readings). The primary CVD outcome during the follow-up period was defined as the development of coronary artery disease, stroke, aortic dissection, or heart failure hospitalization. Result: The mean age of the 297 patients was 65.2 ± 10.5 years; 50.8% were male, and the mean number of antihypertensive medication classes was 3.6 ± 0.6. During a mean follow-up of 6.5 years, 41 CVD events occurred. The primary CVD outcome occurred more frequently in the group of patients with both uncontrolled nighttime home BP (≧120/70 mmHg) and uncontrolled daytime home BP (≧135/85 mmHg) (Figure). The model performance assessed by the C-statistic tended to be improved by adding nighttime home SBP to the base model including confounding factors and office SBP (C-statistic [95%CI], 0.712 [0.652, 0.830] to 0.748 [0.686, 0.851], P = 0.078) and to the model that included the base model and daytime home SBP (C-statistic, 0.714 [0.660, 0.835] to 0.747 [0.702, 0.857], P = 0.065). Adding daytime home SBP did not improve the performance of the base model (C-statistic, 0.712 [0.652, 0.830] to 0.714 [0.660, 0.835], P = 0.872). Conclusion: Our results indicate that nighttime BP measured by the home BP device was associated with an increased risk of CVD events even after adjustment for the daytime home BP level in patients with TRH.