Usefulness of home blood pressure measurement in the morning in patients with type 2 diabetes: long-term results of a prospective longitudinal study.

Previous cross-sectional studies have demonstrated that blood pressure measurements at home (HBP) in the morning display stronger predictive power for micro- and macrovascular complications in type 1 and 2 diabetic patients than casual/clinic blood pressure (CBP) measurements. This longitudinal study investigated which of these measurements offers stronger predictive power for outcomes over 6 years. At baseline, 400 Japanese patients with type 2 diabetes were classified as hypertensive or normotensive based on HBP and CBP measurements. Mean (+/-SD) survey duration of all patients was 42.1 +/- 20.0 months (range, 3-72 months). Primary and secondary endpoints were death and new, worsened, or improved micro- and macrovascular events, respectively. Differences in outcomes for each endpoint between hypertensive and normotensive patients in each group were analyzed using survival curves from Kaplan-Meier analysis and log-rank testing. Associated risk factors related to outcomes were assessed using Cox proportional hazards modeling. On the basis of HBP, cumulative events of death and new or worsened microvascular diseases were significantly higher in hypertensive patients than in normotensive patients. On the basis of CBP, no significant differences were identified. New or worsened macrovascular events were significantly higher in hypertensive patients than in normotensive patients on the basis of both HBP and CBP. One associated risk factor was morning hypertension. A longitudinal study of type 2 diabetic patients demonstrated that elevated HBP in the morning is predictive of micro- and macrovascular complications.