Usefulness of home blood pressure measurement in the morning in type 2 diabetic patients.

Recently, repeated home blood pressure (HBP) measurements in the morning for a long period have been shown to have a stronger predictive power for mortality in patients with hypertension than occasional casual/clinic blood pressure (CBP) measurements. We studied whether HBP in the morning in type 2 diabetic patients is useful for prediction of diabetic complications. The occurrence of diabetic complications (nephropathy, retinopathy, coronary heart disease [CHD], and cerebrovascular disease [CVD]) were examined in relation to morning HBP as well as to CBP in 170 type 2 diabetic patients treated with antidiabetic and antihypertensive drugs. Blood pressure was measured at the clinic during the day and at home after awakening in the morning. Clinic hypertension (CH) and morning hypertension (MH) were defined as systolic blood pressure (SBP) > or =130 mmHg and/or diastolic blood pressure (DBP) > or =85 mmHg. The relation of CH and MH to the prevalence of these events was examined. There were no significant differences in the prevalence of nephropathy, retinopathy, CHD, and CVD between the two groups with (n = 131) and without CH (n = 39), whereas the prevalences of these events in the patients with MH (n = 97) were significantly higher (P < 0.05) than in those without MH (n = 73). The prevalence of nephropathy was highly associated with systolic MH. Elevations of HBP in the morning in diabetic patients are strongly related to microvascular and macrovascular complications, especially nephropathy. It is concluded that the control of MH may prevent vascular complications in type 2 diabetic patients.