Effects of rosiglitazone on plasma brain natriuretic peptide levels and myocardial performance index in patients with type 2 diabetes mellitus
Thiazolidinediones (TZD) have become a powerful tool for lowering insulin resistance. The problem of cardiovascular adverse events including fluid retention and risk of heart failure should be well known and recognised. We aimed to evaluate the long-term effects of rosiglitazone on cardiac function and fluid dynamics. Forty-six type 2 diabetic patients were randomised to treatment with rosiglitazone or metformin or to a control group. There are no significant differences between the groups in the duration of diabetes, HbA1c, plasma brain natriuretic peptide (BNP) levels, body mass index and myocardial performance indexes (MPIs) before the treatment. After three and six months all these parameters were repeated. Rosiglitazone increased plasma BNP levels and worsened MPIs 3 months after the start of treatment. Also left ventricular end-systolic volume increased and weight gain was observed. But these results were statistically non-significant (all p>0.05). When we continued rosiglitazone treatment to six months the increase in BNP levels became soft and statistically significant improvements were seen in MPIs (p<0.01). Also left ventricular end-systolic volume decreased significantly (p=0.004) and weight gain was stopped. In patients with type 2 diabetes, TZD treatment might have slight adverse effects on ventricular contractility and fluid dynamics at the beginning of the therapy. However, these changes seem to stabilise in the long term.