Fig. 4

Multiple linear mixed regression analysis for lung function decline according to adiposity changes in men. Lung function declines were compared between the WHR-decreased and -increased groups in fat- loss and fat-gain group, respectively. Decline of a FVC in the fat-loss group, b FVC in the fat-gain group, c FEV₁ in the fat-loss group, d FEV₁ in the fat-gain group, e FEV₁/FVC in the fat-loss group, and f FEV₁/FVC in the fat-gain group. Individual changes in FMI during follow-up were calculated with linear regression analysis. Participants with a slope of FMI change < 0 were classified under the fat-loss group, and those with a slope > 0 were classified under the fat-gain group. No participant had a zero-degree slope of FMI change throughout the study period. Individual changes in WHR during follow-up were calculated with linear regression analysis. Participants with a lower 30% of WHR change were designated to WHR-decreased group, and those with an upper 30% of WHR change were to WHR-increased group. WHR-stable group comprised the median 40% of participants, which included a zero-degree slope. Results were adjusted for age, height, residential area, follow-up duration, smoking exposure (pack-years), initial lung function, initial FMI, and initial WHR. The gray shadow and numbers in parentheses represent 95% confidence intervals. *P-value between WHR-decreased and -increased group. FEV₁ forced expiratory volume in 1 s, FMI fat mass index, FVC forced vital capacity, WHR waist-to-hip ratio