Microalbuminuria in Patients with Non-Insulin-dependent Diabetes Mellitus Relates to Nocturnal Systolic Blood Pressure

PURPOSE: Microalbuminuria predicts early mortality in non-insulin-dependent-diabetes mellitus patients (NIDDM). Our objective in the present study was to compare and assess the relationship between 24-hour, day and nocturnal ambulatory blood pressure (BP) and urinary albumin excretion rate (UAE) in microalbuminuric and normoalbuminuric NIDDM and in normal control subjects. PATIENTS AND METHODS: In the present cross-sectional study, 24 hour ambulatory BP (daytime BP and nocturnal BP) and HbA1c were compared in microalbuminuric (n = 10) and nonmicroalbuminuric NIDDM patients (n = 10) and in nondiabetic controls (n = 9). None of the patients were taking antihypertensive agents. RESULTS: In the microalbuminuric group, whereas 24 hour and daytime systolic BP differed significantly from control values (P<0.025 and P<0.05 respectively), there was no difference between diabetic groups. However, nocturnal systolic BP in the microalbuminuric group was significantly higher than in the normoalbuminuric diabetic patients (139 vs. 125) (P<0.05) and a significant difference was also found between the NIDDM patients and the control group (139, 125 vs. 114) (P<0.025). In multiple regression analysis, only nocturnal systolic BP showed a significant relationship with UAE (P<0.05). CONCLUSIONS: We suggest that the higher nocturnal systolic blood pressure seen in our microalbuminuric NIDDM patients may contribute to the increased morbidity in this group.