Association between waist circumference change and incident chronic obstructive pulmonary disease among Chinese adults: a 10-year cohort study

The aim of our study was to investigate waist circumference (WC) change and the risk of incident chronic obstructive pulmonary disease (COPD) among Chinese adults. A total of 8164 participants aged > 18 years who attended health examinations with repeat measurements of WC and lung function [forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1)] from 2010 to 2019 were recruited. WC change was categorized as <= - 2.5%, - 2.5 to 2.5%, 2.5% to 5% and > 5% according to sex. Modified Poisson regression models were used to assess the association of WC gain and the risk of COPD. During the 10-year follow-up, a total of 917 COPD cases were identified. From baseline to follow-up, the mean FEV1 decreased from 3.20 to 2.79L among male participants and 2.28-1.95L among female participants. Compared with participants who did not have abdominal obesity, at either, baseline or follow-up, participants with abdominal obesity of both sexes after the follow-up were associated with a greater risk of COPD regardless of abdominal obesity at baseline. The risk of incident COPD increased 19% among male participants (RR = 1.19, 95%CI = 1.04-1.48) and 14% among female participants (RR = 1.14, 95%CI = 1.01-1.40) when WC gain increased > 5% during the 10-year follow-up. The COPD risk decreased 18% among male participants with a WC change <= - 2.5% (RR = 0.82, 95%CI = 0.67-0.99). The risk of incident COPD was positively associated with increasing WC among Chinese adults of both sexes.