Leptin levels are associated with reduced lung function in men with COPD

Abstract

Background: The adipokine leptin associates with cardiovascular diseases (CVD), and with disease severity in COPD. Cardiovascular comorbidities are common in COPD, but it is unclear how leptin is distributed in population-based samples of individuals with COPD.

Aim: To compare the distribution of leptin concentrations in subjects with COPD and normal lung function (NLF), and by COPD severity.

Methods: In 2002-04, subjects with FEV₁/VC ≤0.70 (COPD, n=993) and age and sex-matched referents without COPD were identified from population-based cohorts. In 2005, 593 subjects with COPD (42% women) and 752 referents with NLF (48% women) were examined with structured interview, post-bronchodilatation spirometry and blood sampling. Serum leptin concentrations were determined using ELISA. Statistical analyses were stratified for sex.

Results: Median leptin concentrations did not differ between COPD and NLF. In men with COPD, leptin concentrations were inversely associated with FEV1%predicted (pp) (r=-0.233, p<0.001), and in multiple linear regression models (β [95% CI]), leptin (logarithmized) associated inversely with both FEV₁ (-0.146 [-0.246– -0.045] p=0.005) and FEV₁pp (-0.807 [-1.183– -0.431] p<0.001) after adjustments for age, BMI and smoking. Leptin did not associate with any lung function parameter in women with COPD, nor in men or women with NLF.

Conclusion: In this population-based sample, reduced lung function was associated with increased serum leptin concentrations among men, but not women, with COPD. Further studies are needed to evaluate a possible sex-dependent association with regard to leptin and CVD in COPD.