Masked Hypertension, Urinary Albumin Excretion Rate, and Echocardiographic Parameters in Putatively Normotensive Type 2 Diabetic Patients

OBJECTIVE: To evaluate the impact of masked hypertension in normotensive type 2 diabetic patients on microvascular complications and echocardiographic parameters. RESEARCH DESIGN AND METHODS: A cross-sectional study was conducted in 135 normotensive patients with type 2 diabetes. Patients underwent urinary albumin excretion rate (UAER) measurement, echocardiography, and 24-h ambulatory blood pressure monitoring (ABPM). Patients with increased daytime blood pressure levels (> or = 135/85 mmHg) were classified as having masked hypertension. RESULTS: The prevalence of masked hypertension was 30% (n = 41). Normotensive and masked hypertensive subjects, based on ambulatory blood pressure, were not different in terms of age, diabetes duration, smoking status, BMI, waist circumference, serum creatinine, glycemic, or lipid profiles. The office systolic blood pressure was higher in those with masked hypertension (127.8 +/- 7.5 vs. 122.9 +/- 10.2 mmHg, P = 0.003) than in the normotensive group. UAER also was increased in the group with masked hypertension (21.3 microg/min range 2.5-1,223.5 vs. 8.1 microg/min 1.0-1,143.0, P = 0.001), as was the interventricular septum (1.01 +/- 0.15 vs. 0.94 +/- 0.13 cm, P = 0.015) and posterior wall (0.96 +/- 0.12 vs. 0.90 +/- 0.10 cm, P = 0.006) thickness. After adjustments for diabetes duration, sex, smoking, LDL cholesterol, and A1C values, all associations were sustained for daytime systolic blood pressure but not for office systolic blood pressure. CONCLUSIONS: Type 2 diabetic patients with masked hypertension have higher UAER as well as enlargement of ventricular walls compared with the normotensive patients, according to ABPM. Therefore, ABPM is important to identify this high-risk group so as to be able to take interventionist measures.