Maximum home blood pressure and cardiovascular outcomes in patients with type 2 diabetes: KAMOGAWA-HBP study

Objective: The maximum blood pressure was reported as a possible marker of organ damage. We previously showed that maximum home blood pressure was significantly associated with development of diabetic nephropathy. In the same cohort of patients with diabetes as in the previous study, this study aimed to evaluate the prognostic blood pressure values for the onset of first cardiovascular events. Methods: This retrospective cohort study included 1082 patients with type 2 diabetes (47.0% female, median age 65.0) without a history of macrovascular complications. Blood pressure measurements were performed in triplicates every morning and evening for 14 consecutive days from the start of the study. Cox hazards model was used to evaluate the risk of primary endpoint, which was defined as the onset of first major cardiovascular event. Results: The primary endpoint occurred in 119 patients (incidence rate, 15.7/1000 person-years) during an average of 7.0-year follow-up. The adjusted hazard ratios (95% confidence interval [CI]) of maximum morning systolic blood pressure (SBP) and maximum evening SBP for cardiovascular events were 1.12 (1.01-1.24) and 1.19 (1.07-1.31), respectively, adjusted by sex, duration of diabetes, body mass index, hemoglobin A1c, low density lipoprotein cholesterol, smoking status, and use of antihypertensive medications. The cutoff values of maximum blood pressure for the events were 150 mmHg in the morning (hazard ratio, 1.73; 95% CI, 1.07-2.81) and 157 mmHg in the evening (hazard ratio, 2.30; 95% CI, 1.46-3.61), using the Youden's index. Conclusion: Maximum home blood pressure is a predictor of subsequent cardiovascular events in patients with type 2 diabetes.