Blood pressure means rather than nocturnal dipping pattern are related to complications in Type 2 diabetic patients

Aim To determine whether systolic and diastolic blood pressure (BP) means, during ambulatory BP monitoring (ABPM), are more strongly correlated with microvascular complications and echocardiographic structural alterations than night-time/daytime (N/D) BP ratio. Methods A cross-sectional study was conducted in 270 Type 2 diabetes mellitus (DM) outpatients who underwent clinical and laboratory investigations, urinary albumin excretion rate (UAER) determination, echocardiography, office and 24-h ABPM (Spacelabs 90207). Results UAER, after multivariate adjustments, was associated with office BP (systolic: R-a(2) 0.162, P < 0.001; diastolic: R-a(2) 0.124, P < 0.001) and ABPM (24-h systolic: R-a(2) 0.195, P < 0.001; 24-h diastolic: R-a(2) 0.197, P < 0.001) but not with N/D BP ratios (systolic: R-a(2) 0.062, P = 0.080; diastolic: R-a(2) 0.063, P = 0.069). Similar results were observed for echocardiographic parameters. The presence of retinopathy was associated only with night-time BP values [systolic means: odds ratio (OR) 1.13, 95% confidence interval (CI) 1.03-1.24 and diastolic means: OR 1.21, CI 1.04-1.40 and N/D diastolic BP ratio > 0.90, OR 3.21, CI 1.65-6.25]. UAER and echocardiographic structural alterations had more consistent correlations of a greater magnitude with systolic BP means than with N/D BP ratios. The nocturnal BP values appear to be more relevant for diabetic retinopathy. BP measurement in patients with Type 2 DM should take into account the 24-h period rather than focusing on a specific time span of BP homeostasis.