Ambulatory blood pressure and urinary albumin excretion in diabetic (non–insulin-dependent and insulin-dependent) hypertensive patients: Relationships at baseline and after treatment by the angiotensin converting enzyme inhibitor trandolapril

Abstract

The aim of the present study was to examine the relationships between ambulatory blood pressure (ABPM) and urinary albumin excretion (UAE) in diabetic (non–insulin dependent [NIDDM] and insulin-dependent [IDDM]) hypertensives at baseline and after treatment by an angiotensin converting enzyme (ACE) inhibitor. After a 3-week placebo period, patients were treated for 16 weeks with trandolapril, 2 to 4 mg/day. The UAE and blood pressure (mercury sphygmomanometer and 24-h ABPM) were measured at baseline and repeated on trandolapril. Predictive factors of abnormal UAE (24-h UAE ≥30 mg) were determined using univariate and multivariate analysis (logistic regression). Predictors of UAE decrease were also searched. One hundred seventy-one patients entered the analysis. Baseline office BP was 164 ± 14/97 ± 6 mm Hg and 24-h BP was 142 ± 17/83 ± 10 mm Hg. Seventy-four patients (43%) had UAE ≥30 mg. Independent risk factors for abnormal UAE were nighttime diastolic BP (odds ratio [OR] = 4.1, confidence interval [CI] = 2.0 to 8.6, P = .0001), diabetes duration (OR = 2.4, CI = 1.1 to 5.0, P = .025), and presence of retinopathy (OR = 3.2, CI = 1.0 to 10.0, P = .047). Conversely, office BP level was not significantly related to UAE. On treatment, office BP levels decreased to 143 ± 13/82 ± 8 mm Hg ( P < .0001) and 24-h BP levels to 134 ± 17/78 ± 9 mm Hg ( P < .0001). In the abnormal UAE group, UAE significantly decreased from 76 to 50 mg/day ( P = .006). After treatment, independent predictive factors of abnormal UAE were: on-drug fasting plasma glucose (OR = 3.5, CI = 1.7 to 7.4, P = .0009) and on-drug nighttime diastolic BP (OR = 3.5, CI = 1.7 to 7.4, P = .001). The only predictor of UAE decrease was a 24-h systolic BP decrease (OR = 2.3, CI = 1.3 to 4.3, P = .007). We conclude that in diabetic hypertensives with abnormal UAE, trandolapril exhibited a sustained 24-h antihypertensive effect and provided a consistent reduction of microalbuminuria. This study confirmed the superiority of ABPM over clinical BP to predict target organ damage.