Serum leptin – is it associated with levels of airway responsiveness?

Background: Serum leptin levels reflect the amount of adipose tissue for a given level of BMI. Knowledge of the association between serum leptin and levels of lung function and airway responsiveness may therefore increase our understanding of the effects of adiposity on airway pathophysiology, also in non-obese subjects. Objective: We aimed to explore, in a random population sample of primarily non-obese subjects, if serum leptin levels were associated with FEV1 and airway responsiveness, also after adjusting for BMI. Methods: We examined the cross-sectional associations between serum leptin levels and measurements of lung function including FEV1 and airway responsiveness to methacholine in 163 free-living individuals aged 27-37 who attended the final visit in the Copenhagen Cohort Study, a random sample population study. Results: Fifty-seven percent of subjects were females and 87% were non-obese (BMI Conclusion: In this cross-sectional population study, increased serum leptin was associated with a low level of FEV1 and increased degree of airway responsiveness to methacholine also after adjustment for BMI. This suggests that serum leptin could be a biomarker superior to BMI to use in future studies that explore the effects of adiposity on airway pathophysiology.