The Change of Plasma Ghrelin and Leptin Levels by the Development of Type 2 Diabetes Mellitus in Patients With Alcohol Dependence

Background: There have been lots of studies about the relationship between chronic use of alcohol and the development of type 2 diabetes mellitus (T2DM). Chronic use of alcohol can be affected by the altered level of ghrelin and leptin which regulate food-seeking behavior having similar mechanism of controlling alcohol-craving behavior. Those peptides are known to be correlated with T2DM. Ghrelin and leptin also have been regarded as possible regulators of glucose metabolism and insulin function. Hence, there is the possibility that ghrelin and leptin can be related with deteriorated pathophysiology of T2DM in alcoholic patients. Methods: Patients with alcohol dependence diagnosed by Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) underwent an 75 g oral glucose-tolerance test (OGTT), to classify them to normal glucose tolerance (NGT, n = 52), pre-diabetes including impaired glucose tolerance (IGT), impaired fasting glucose level (IFG) and combination of IGT and IFG (Pre-DM, n = 26) and T2DM (n = 24) groups. Fasting plasma ghrelin and leptin levels were compared among groups. Results: There was no difference of ghrelin concentration among the groups but the leptin concentration was significantly different between NGT and T2DM group (p < 0.05). Increased leptin levels were significantly correlated with body mass index (BMI), insulin level, and insulin resistance. Conclusions: Chronic alcohol drinking might produce leptin resistance which makes leptin significantly correlated with fasting insulin concentration and insulin resistance. Therefore, we suppose that increased level of leptin by chronic alcohol use could be one of the main mechanisms that develop insulin resistance in alcoholic patients.