Opposite effects of insulin-like molecules and leptin in coronary heart disease of type 2 diabetes: Preliminary data

Abstract

Introduction Leptin and insulin have been reported to be risk factors for coronary heart disease (CHD) in the general population, but their role in type 2 diabetes still remains unclear. Materials and methods The role of leptin and insulin upon CHD in type 2 diabetes was assessed in 154 patients, aged 31–77 years, who were treated with oral anti-diabetic agents. Multivariate logistic regression analyses were used with CHD (an established history of CHD or an abnormal treadmill test) as dependent, and leptin, insulin and potential confounders as independent variables. Results Endogenous insulin was significantly associated with CHD in a model controlling for gender, age, duration of diabetes, body mass index, smoking and leptin (Odds ratio 1.45 per decile, 95% confidence interval 1.11–1.90). Improving control for confounding by replacing body mass index by subcutaneous fat (CT-measured at the L4–L5 level) and height in this model, resulted in a significant negative association between leptin and CHD (OR 0.60, 95% CI 0.37–0.96). Discussion Leptin might have a beneficial effect on CHD in type 2 diabetes, probably by counteracting the effect of insulin-like molecules or insulin resistance. The effect was elucidated only after careful control for confounding by subcutaneous fat, the main source of leptin production.