Rosiglitazone lowers C-reactive protein levels in hypertensive type 2 diabetic patients

Abstract

Accumulating data indicate that thiazolidinediones (TZD) present beneficial effects for the cardiovascular system beyond glycemic control, such as triglyceride reduction, HDL-cholesterol elevation and decrease in plasminogen activator inhibitor-1 levels. The aim of this study was to determine the effect of rosiglitazone on C-reactive protein, an inflammation marker associated with an increased risk for cardiovascular disease, in patients with hypertension and Type 2 diabetes. A total of 40 Type 2 diabetic subjects, already on 15 mg glibenclamide daily, but with a poor glycemic control, were included in the study. Patients had either established hypertension, poorly controlled under antihypertensive treatment, or newly diagnosed mild hypertension without medication. In 20 of the subjects rosiglitazone 4 mg daily was added-on therapy for 26 weeks, while the rest remained only with the preexisting treatment to serve as control group. At baseline and the end of the study subjects gave blood samples where high sensitive C-reactive protein (hs-CRP) was measured with the use of a latex-enhanced immunonephelometric method. At the end of the study, rosiglitazone treatment was associated with a significant reduction in hs-CRP levels versus baseline (from 0.53±0.11 to 0.39±0.12 mg/dL, P<0.05). In contrast, no significant change in hs-CRP levels was observed in the control group (from 0.49±0.19 to 0.56±0.09 mg/dL, P=0.18). Between-groups comparison revealed also a significant difference for hs-CRP (P<0.05). If the rosiglitazone group is divided in subgroups of men (n=9) and women (n=11), or patients with (n=10) and without (n=10) preexisting antihypertensive treatment, a downward trend in hs-CRP levels is still observed in the subgroups, but the reduction is significant only in that of patients without antihypertensive treatment. Treatment of hypertensive Type 2 diabetic patients with rosiglitazone resulted in a significant reduction of hs-CRP levels. This finding indicates that rosiglitazone possibly exerts a vasculoprotective action, which may be important for this type of patients, who are in high risk for atherosclerotic complications.