Long-term Effects of Gastric Bypass Surgery in Patients with Obstructive Sleep Apnea

Background: Obstructive sleep apnea is a common disorder involving, intermittent mechanical obstruction of the upper airway during sleep. Obesity is the most powerful risk factor for obstructive sleep apnea. Objective: This study aimed to investigate the long-term effect of Roux-en-Y gastric bypass bariatric surgery on patients with obstructive sleep apnea. Methods: This study included patients were referred for bariatric surgery (Roux-en-Y gastric bypass) to control symptoms and complications of obesity during a 5-year period. An overnight sleep study was performed for each patient before and after the bariatric surgery, to study its effect on different obstructive sleep apnea-related variables. Results: This study included 179 patients (mean age 35.9 ± 10.7 years). The mean duration from preoperative assessment to postoperative assessment was 2.4 ± 2.2 years. The mean change in body mass index and weight showed a decrease of 16.0 ± 16.0 kg/m2 and48.7 ± 25.9 kg, respectively. The apnea hypopnea index decreased by a mean of 22.6 ± 26.3 events/hour. Conclusion: We concluded that a decrease in the body mass index by 1 kg/m2 could predict a decrease in the apnea hypopnea index by 0.46 events/hour. Moreover, after mean follow-up duration of 2.4 years, 84.3% of mild and 83.3% of moderate obstructive sleep apnea patients became normal postoperatively.