INTRODUCTION: Obstructive sleep apnea (OSA) is common among candidates for bariatric surgery and is often underdiagnosed. Given that obesity and OSA share comorbidities and mutually reinforce each other, it is important to identify factors that predict OSA resolution after bariatric surgery. However, studies on this topic are limited and offer contradictory results. The objective of the study was to identify predictors of OSA resolution one year after bariatric surgery. METHODS: A prospective study was conducted with bariatric surgery candidates aged 18 to 65. Patients underwent preoperative cardiorespiratory polygraphy (PR) and an otorhinolaryngological examination. A follow-up PR was performed one year after surgery. A multivariate analysis was conducted, examining anthropometric, metabolic, and upper airway anatomical variables to determine predictors of resolution. RESULTS: The prevalence of OSA was 75%. Predictors of resolution included preoperative body mass index (BMI), neck circumference and age. Each additional kg/m² in BMI reduced the probability of resolution by 14% (OR = 0.86
P = .037), each additional centimeter of neck circumference reduced the probability by 16% (OR=0.84
P = .018), and each year of age reduced the probability by 11% (OR=0.89
P = .009). CONCLUSIONS: The prevalence of OSA in bariatric patients is high, and BMI, neck circumference, and age are predictive factors of OSA resolution after bariatric surgery.