Background: Obesity has proven to be associated with respiratory symptoms and impaired pulmonary function, which could increase the incidence of postoperative complications after bariatric surgery. However, the component of obesity that has the most influence on pulmonary function has not been identified, especially in Asian-Pacific populations.
Methods: This cross-sectional study enrolled obese Chinese patients >or=18 years of age with a body mass index (BMI) >32 kg/m(2), who were being evaluated for bariatric surgery. All patients performed pulmonary function test, and the results were analyzed according to various anthropometric measurements. Multiple-regression analyses were also conducted and adjusted for age, sex, and smoking history to determine the factors that impaired the pulmonary function of the obese patients.
Results: A total of 150 consecutive patients were enrolled from July 2007 to August 2008. We found that body weight, BMI, waist circumference (WC), hip circumference, and waist-to-height ratio but not waist-to-hip ratio had a significant correlation with decreased forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), total lung capacity (TLC), vital capacity (VC), and increased diffusing capacity of the lung for carbon monoxide to alveolar gas volume. After multiple linear regression analysis, only WC was associated with reductions in FEV1, FVC, TLC, and VC.
Conclusions: Obesity is associated with a restrictive pattern of impaired pulmonary function in various anthropometric parameters measured in obese Chinese adults in Taiwan. Among these parameters, WC had the greatest impact on pulmonary function, which could also implicate the rate of postoperative complication and the need of more intensive care after bariatric surgery.