Impact of leptin levels upon left ventricular structural abnormalities in non insulin dependent diabetics

ABSTRACT

Non-insulin-dependent diabetes mellitus adversely affects left ventricular [LV] structure. Recent studies have showed that leptin increases in insulin-resistant states, such as obesity and hypertension. The levels of plasma leptin have been found to be associated with LV myocardial growth. This study aimed to assess fasting serum leptin concentrations in the type 2 diabetic patients and to find the correlation between fasting serum leptin concentrations and the LV structural changes in the type 2 diabetic patients. Twenty four type 2 diabetic patients aged 51.1 +/- 7.2 years with LV structural changes defined as fasting plasma glucose >/= 126mg/di. Twenty four type 2 diabetic patients without LV structural changes, aged 47.6 +/- 9.0 years, were the controls. The following LV structural parameters were assessed by Two-dimensional echocardiography left ventricular end-diastolic [LVEDD], left ventricular end-systolic diameter [LVESD], interventricular septal thick-ness [IVST], left ventricular posterior wall thickness [PWT], relative wall thickness [RWT] and left ventricular mass index [LVMI]. Left atrium [LA] and aortic root [Ao] dimensions were also assessed. Fasting serum leptin and insulin, fasting blood sugar [FBS] and glycosylated hemoglobin [HbAlc] were assessed. The correlations of leptin to LV structural parameters were statistically analyzed. Body mass index [BMI], FBS and fasting serum concentrations of leptin and insulin were significantly greater in the case patients than in the controls. Three were statistically significant differences between groups in all echocardiographic parameters apart from LVEDD, LVESD, RWT, LA and AO. In the case group, Leptin was positively correlated with FBS and insulin. Also, a significant correlation was found between serum leptin and the following echocardiographic parameters PWT, IVST, SWT and LVME in the case group. Hyperleptinemia in type 2 diabetic patients with LV structural changes and the association of leptin with indexes of LV structure may reflect its role in the development of myocardial wall thickening in non-insulin dependent diabetes mellitus