**5. Weight loss by bariatric surgery**

OSA is seen in about 45% of bariatric patients [28]. Surgically induced weight loss showed significantly improves obesity-related sleep apnea. It decreased the mean RDI to 15 ± 2 from 51 ± 4 (preoperatively). In addition, oxygen saturation, sleep efficiency, repaid eye movement latency and the requirement for continuous positive airway pressure [29].
