Association between risk factors of metabolic syndrome with lung function

BACKGROUND/OBJECTIVES: Increased evidence suggests that metabolic syndrome (MetS) is correlated with lung function impairment. This study aimed to explore the associations between MetS risk factors and the lung function. SUBJECTS/METHODS: The cross-sectional study included 6945 participants attending health examination between 2010 and 2012 in Taiwan. MetS was assessed according to the criteria of National Cholesterol Education Program III. Spirometric parameters were measured to define lung function. The relationships were tested using multiple linear regression and logistic regression analyses. RESULTS: The prevalence of MetS was significantly higher in males (16.2%) than females (3.8%). Although the prevalence of restrictive lung disease (RLD) was comparable between genders (20.7 and 21.0%), males with co-existent MetS had a higher prevalence of RLD than females (27.4 vs. 18.0%). Abdominal obesity, indicated by waist circumference (WC) and weight-to-height ratio (WHtR), was the most significant factor associated with lung function decline. Other components of MetS also showed statistically significant relationships, but very weak, with lung function. There was a trend toward an increased prevalence of RLD with the increasing number of MetS scores in males, independent of age, smoking, and body mass index. CONCLUSIONS: Abdominal obesity was the key component of MetS associated with mechanical effect on lung function impairment in a prime-age adult population. Although RLD was not associated with increased probability of having MetS, the participants with more MetS scores were at a higher risk of losing lung function.