Evolution and predictive factors of improvement of obstructive sleep apnea in an obese population after bariatric surgery

Abstract

Study Objectives: Our objectives were to determine in an obese population (body mass index > 35 kg/m2) the number of patients, after gastric bypass (GBP), who no longer met French Ministry of Health criteria for utilizing positive airway pressure (PAP), and the predictive factors of obstructive sleep apnea (OSA) improvement. Methods: Between June 2012 and August 2014 we diagnosed OSA in 129 incident patients requiring PAP therapy before GBP. A postoperative sleep recording was undertaken for 44 of these patients after a weight loss of at least 10%. Results: Most of the patients showed severe OSA with a mean [standard deviation] apnea-hypopnea index (AHI) of 52.8 [23.8] events/h. The body mass index was 46.1 [5.1] kg/m2. All the patients were treated via PAP and most of them via auto-titrating PAP with a range of 4–16 cmH2O. Following the GBP, in 31 patients (70.5%) OSA was improved, allowing PAP to be stopped (AHI < 15 events/h). The Epworth Sleepiness Scale score, the modified Medical Research Council dyspnea scale, the loudness of snoring, and sleep structure were improved. AHI was decreased by a mean of 40.9 [22.4] events/h (P < .001). In a multivariate logistic regression model, age (P = .018) and sleep oxygen desaturation index (P = .049) appeared to predict improvement of OSA. Conclusions: After GBP, 70.5% of the patients no longer met French Ministry of Health criteria for utilizing PAP, allowing discontinuation of this treatment. At diagnosis, a younger age and a less severe sleep oxygen desaturation were predictive factors of this improvement.