SAT-112 Improvement of Pulmonary Function Test after Bariatric Surgery in Asthma Patients

Background: Obesity is an arising public health problem that found to affect millions of Americans and is a burden cost of U.S. government expense in health systems (1). The association between obesity and asthma has been established form multiple studies (2). There is an evidence that weight loss may improve asthma outcome. However, the effect of bariatric surgery to improve a pulmonary function test in asthmatic patients is still inconclusive. This systematic review and meta-analysis of observational studies assessed the effect of bariatric surgery in patients with asthma. Objectives: To explore whether there is an improvement in pulmonary function test and respiratory symptoms in patients with asthma after bariatric surgery. Setting: Meta-analysis of published studies Methods: We as authors comprehensively searched the databases of MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL). The inclusion criteria were published studies evaluating effects of bariatric surgery in patients with asthma. The outcome of interest was forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC. A meta-analysis comparing the pre- and post-surgery spirometric measure was performed. Results: From 25 full-text articles, six observational studies met our inclusion criteria and were included in the meta-analysis based on the random-effects model. There was a significant increase in FEV1 and FVC after bariatric surgery with a standardized mean difference of 0.22 L (95% CI: 0.14-0.30) and 0.58 L (95% CI: 0.16-1.00), respectively. There was no significant change in FEV1/FVC after bariatric surgery. Conclusions: Many theories have explained the linked mechanisms of asthma in obesity. Obesity has shown to be a risk factor for asthma and appeared to cause 2-3 times increased the risk of developing asthma. The primary mechanical defect is explained with a high percentage of excess body fat that compresses the lung capacity and limits the free air movement. From our study, improvement in some pulmonary function test in asthmatic patients was observed after bariatric surgery. Further studies should evaluate the risks and benefits of bariatric surgery in obese patients with asthma. References: 1. Akinbami, L.J., et al., Trends in asthma prevalence, health care use, and mortality in the United States, 2001-2010. NCHS Data Brief, 2012(94): p. 1-8. 2. Ali, Z. and C.S. Ulrik, Obesity and asthma: a coincidence or a causal relationship? A systematic review. Respir Med, 2013. 107(9): p. 1287-300.