Vascular endothelial functions, carotid intima-media thickness, and soluble CD40 ligand levels in dipper and nondipper essential hypertensive patients

Abstract

Objective: The lack of nocturnal decline in blood pressure (BP) is associated with an increase in cardiovascular events. Soluble CD40 ligand (sCD40L) is involved in the pathogenesis of risk factor-related vascular damage. The purpose of this study was to examine the relationship between vascular endothelial functions, carotid intima-media thickness (cIMT), plasma sCD40L levels and circadian BP profile in patients with essential hypertension.

Material and methods: The study population consisted of 81 essential hypertensive out-patients. BP dipping was defined as a night-to-day systolic and diastolic decrease >or=10%. Forty-seven dipper and 34 nondipper patients were compared. High sensitivity C-reactive protein (hs-CRP), sCD40L and urinary albumin were measured. Brachial artery flow-mediated dilatation (FMD) and cIMT was compared between the groups.

Results: sCD40L level (3.28 +/- 2.08 and 2.30 +/- 1.99 ng/ml, respectively, P = 0.036) and urinary albumin concentration (36.7 +/- 20.1 and 23 +/- 29.7 mg/l, respectively, P < 0.0001) were higher in nondippers than in dippers. Serum hs-CRP levels were not significantly different. FMD was found higher in dippers than nondippers (11.8 +/- 3.9% and 6.6 +/- 2.2%, respectively, P < 0.0001). The average cIMT was significantly higher in nondippers than dippers (0.928 +/- 0.060 Vs. 0.734 +/- 0.134 mm; P < 0.0001).

Conclusions: Nondipper patern has an additional negative effect on endothelial functions in hypertensive patients. Nondippers have enhanced sCD40L levels, which may contribute to their increased susceptibility to develop vascular damage.