Masked hypertension, nocturnal blood pressure and retinopathy in normotensive patients with type 1 diabetes

Aim: To analyze the prevalence of masked hypertension and its possible association with microvascular complications in patients with type 1 diabetes (T1D). Methods: A cross-sectional study was conducted in 188 consecutive normotensive patients at the office with T1D without renal replacement therapy or previous renal transplant. All patients were assessed regarding the presence of diabetic retinopathy (DR) (direct and indirect fundoscopy), urinary albumin excretion rate (immunoturbidimetry), and ambulatory blood pressure monitoring (ABPM) (Spacelabs 90207). Results: Masked hypertension was observed in 14 (13.6%) out of 103 clinical normotensive patients and in 7.4% of the entire cohort. Twenty-three percent of patients with clinical normotension had masked nocturnal hypertension. DR was associated with night systolic and diastolic BP [OR of each S mmHg change 1.41 (95%CI: 1.09-1.83, P = 0.009) and 1.40 (95%CI: 1.02-1.93, P = 0.04), respectively] and with masked nocturnal hypertension [OR: 3.23 (95%CI: 1.29-8.11, P = 0.01)]. Conclusions: In T1D patients with clinic BP < 130/80 mmHg, masked hypertension and especially masked nocturnal hypertension are present. Normotensive patients with nocturnal BP > 120/70 mmHg have higher presence of DR, and only will be identified through ABPM. (C) 2009 Elsevier Ireland Ltd. All rights reserved.