Increased leptin/adiponectin ratio relates to low-normal thyroid function in metabolic syndrome

Background: Low-normal thyroid function within the euthyroid range may contribute to increased atherosclerosis susceptibility. The leptin/adiponectin (L/A) ratio is associated with cardiovascular disease and reflects adipose tissue dysfunction. Relationships of the L/A ratio with low-normal thyroid function are unknown. Methods: Relationships of thyroid stimulating hormone (TSH) and free thyroxine (free T-4) with leptin, adiponectin and the L/A ratio in euthyroid subjects were documented in 67 fasting subjects with metabolic syndrome (Mets) and 86 euthyroid subjects without MetS (TSH and free T-4 levels within the institutional reference range). Results: Neither plasma leptin nor adiponectin was significantly correlated with TSH or free T-4 in subjects with and without MetS. In the whole group, high sensitivity C-reactive protein (hs-CRP) was positively correlated with the L/A ratio (r = 0.485, P