Leptin production by the adipose tissue is decreased in obesity associated with severe metabolic syndrome

Aim: To evaluate the associations between leptinemia and metabolic syndrome (MetS). Patients/methods: Fifty-one obese adults (9 men; BMI 46.2±10.0 kg/m²) were submitted to clinical examination, determinations of body fat mass (BF) and resting energy expenditure (REE), and to hormonal and biochemical analysis. Patients were categorized into three groups, according to the number of criteria for MetS: Group I: 0-1; Group II: 2; and Group III: ≥3 criteria. Results: Leptinemia adjusted for BF (LepBF) was inversely correlated with weight (r=-0.41; p=0.027), REE (r=-0.34; p=0.01) and number of MetS criteria (r=-0.32; p=0.02). There was no difference in absolute leptinemia (LepA) among groups. LepBF in group III (0.58±0.27 ng/ml/kg) was significantly lower compared to I (0.81±0.22 ng/ml/kg; p=0.03) and II (0.79±0.30 ng/ml/kg; p=0.02). Conclusion: Leptin production by the adipose tissue is decreased in obese subjects fulfilling ≥3 MetS criteria, suggesting a state of relative leptin deficiency.