Interactions between leptin and insulin resistance in patients with prediabetes, with and without NAFLD

This study explored the link between insulin sensitivity, insulin resistance and leptinaemia in people with prediabetes with and without non-alcoholic fatty liver disease (NAFLD). A total of 143 prediabetes patients were evaluated in the study. Ultrasonography was used for diagnosis of NAFLD, and fasting insulin, postprandial insulin, leptin levels, common clinical/biochemical determinations were determined. In total, 69 (48.25%) of the patients were diagnosed with NAFLD and 74 (51.75%) without NAFLD. Leptin values correlated statistically with fasting insulin in prediabetes patients, while in the patients that were also diagnosed with NAFLD the correlation was stronger. Values of log-leptin <1 ng/ml were found in 64% of patients with prediabetes without NAFLD, and in 2% of patients with prediabetes and NAFLD. In the context of the association between serum leptin levels and a worse biochemical profile in prediabetes patients on one hand, and fatty liver disease and a worse biochemical profile in prediabetes patients on the other, leptin can be considered a possible candidate molecule that mediates the biochemical alterations identified in these patients.