Abstract
The aim of this study was to evaluate the effects of barnidipine+losartan compared with telmisartan+hydrochlorothiazide on several parameters of insulin sensitivity in patients with hypertension and type 2 diabetes mellitus. We enrolled 148 normocholesterolemic patients with mild-to-moderate hypertension and type 2 diabetes mellitus. Patients were treated with barnidipine, 20 mg day(-1), in combination with losartan, 100 mg day(-1), or with telmisartan+hydrochlorothiazide, 80/12.5 mg day(-1), for 6 months. We assessed blood pressure (BP) on a monthly basis; additionally, blood samples were collected to assess, at baseline and after 6 months, the following parameters: fasting plasma glucose; glycated hemoglobin; fasting plasma insulin; HOMA index; and some adipocytokines, such as adiponectin (ADN), resistin, leptin, visfatin and vaspin. Patients were also subjected to an euglycemic hyperinsulinemic clamp to assess the M value and glucose infusion rate to ascertain their insulin sensitivity. One hundred and forty-one patients completed the study. The BP was reduced in both groups, although the reduction was greater with barnidipine+losartan (P<0.001 vs. baseline and P<0.01 vs. telmisartan+hydrochlorothiazide). Barnidipine+losartan increased the M value and glucose infusion rate during the euglycemic hyperinsulinemic clamp (P<0.05 vs. baseline and vs. telmisartan+hydrochlorothiazide). With respect to the levels of adipocytokines, ADN was increased (P<0.05), and resistin and leptin were reduced from baseline with barnidipine+losartan (P<0.05 vs. baseline), but they were not reduced with telmisartan+hydrochlorothiazide. Visfatin and vaspin were reduced by barnidipine+losartan compared with baseline (P<0.05). The adipocytokine levels obtained with barnidipine+losartan were significantly better than those obtained with telmisartan+hydrochlorothiazide (P<0.05 for all parameters). In addition to providing a greater BP reduction, barnidipine+losartan improved the insulin sensitivity, as assessed by an euglycemic hyperinsulinemic clamp, and improved some of the adipocytokines related to insulin resistance.