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

Abstract

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 (Ն135/85 mmHg) were classified as having masked hypertension.RESULTS -The prevalence of masked hypertension was 30% (n ϭ 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 Ϯ 7.5 vs. 122.9 Ϯ 10.2 mmHg, P ϭ 0.003) than in the normotensive group. UAER also was increased in the group with masked hypertension (21.3 g/min [range 2.5-1,223.5] vs. 8.1 g/min [1.0 -1,143.0], P ϭ 0.001), as was the interventricular septum (1.01 Ϯ 0.15 vs. 0.94 Ϯ 0.13 cm, P ϭ 0.015) and posterior wall (0.96 Ϯ 0.12 vs. 0.90 Ϯ 0.10 cm, P ϭ 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. Diabetes Care 30:1255-1260, 2007H ypertension is a major risk factor for the development and progression of chronic complications in type 2 diabetes (1,2). Blood pressure evaluation over a 24-h ambulatory blood pressure monitoring (ABPM) period correlates better with outcomes than ordinary office blood pressure measurements in both hypertensive subjects (3) and the general population (4). In addition, systolic ambulatory blood pressure is associated with the urinary albumin excretion rate (UAER), even in normoalbuminuric type 2 diabetic patients (5). The ABPM also allows the analysis of other blood pressure parameters, otherwise not documented by the office blood pressure evaluation, such as nocturnal dipping patterns, presence of white-coat hypertension, blood pressure loads, and a novel subgroup of patients with masked hypertension (6).Masked hypertension is defined by elevated mean daytime blood pressure levels at 24-h ABPM (blood pressure Ն135/85 mmHg) in office normotensive individuals (blood pressure Ͻ140/90 mmHg). In a population-based study, it was detected in 9% of the individuals tested (7). Before the ABPM became available, these patients were not detected and were believed to have the same risk for cardiovascular events as the normotensive population. However, e...

Abnormalities in ambulatory blood pressure monitoring in hypertensive patients with diabetes

“…Prevalence of masked hypertension in series evaluating normotensive patients with diabetes was 25-50% [19][20][21][22] or 440% in diabetic hypertensives showing adequate control of BP. 23 These studies have shown that masked hypertension conferred unfavorable outcomes, thus evaluation of ambulatory BP may be indicated in normotensive diabetic patients 21 and in hypertensive cases with controlled office BP.…”

Masked nocturnal hypertension—a novel marker of risk in type 2 diabetes

“…Despite this, in previous investigations of the prevalence of masked hypertension in diabetes, the definition of masked hypertension has been restricted to out-of-clinic BP values obtained during the awake part of the day, using either self-measured BP [1,2] or ambulatory BP [3,4,13]. We report for the first time the prevalence of MNHT in type 2 diabetes, and conclude that it is more common than masked day-time hypertension and identifies more accurately the patients at elevated risk for macrovascular complications of diabetes.…”

“…In type 2 diabetes, masked hypertension-defined as normal blood pressure when measured in the clinic but elevated BP when measured out of the clinic during the awake part of the day-is associated with an increased prevalence of retinopathy, nephropathy and coronary heart disease [1] and with target organ damage [2][3][4]. However, it is not known whether masked nocturnal hypertension (MNHT)-defined as normal BP when measured in the clinic but elevated BP when measured away from the clinic during the night-is a more useful tool for the identification of patients at high risk than masked hypertension.…”

Blood pressure responses to exercise in type II diabetes mellitus patients with masked hypertension

“…1 Patients with MH may have exaggerated BP response to ordinary daily stressors, with physical exercise being one possible trigger. The results of this cross-sectional study showed that type II diabetic patients with MH have an exaggerated BP response to exercise, which may confer an increased cardiovascular risk.…”

“…1,2 MH has been observed in 30% of office normotensive type II DM patients and is associated with higher urinary albumin excretion rate and increased left ventricular mass in comparison with patients with normal BP levels at both the office and ABPM. 1 Patients with MH may have exaggerated BP response to ordinary daily stressors, with physical exercise being one possible trigger. Therefore, the aim of this study was to evaluate the response of BP during exercise in normotensive and MH type II DM patients.…”