HEALTH CARE UTILIZATION AND COSTS OF BARIATRIC SURGERY PATIENTS WITH VS. WITHOUT COMORBID OBSTRUCTIVE SLEEP APNEA

Abstract

Obstructive sleep apnea (OSA) is underrecognized. Between 10% and 69% of preoperative patients have undiagnosed OSA. To reduce the risk of peri-operative complications related to undiagnosed OSA, patients planned to undergo bariatric surgery are screened for OSA. To understand the OSA detection rate with screening practices, the prevalence of OSA within patients who underwent publicly funded bariatric surgery in Ontario between 2010 and 2016 was measured. Secondly, to understand the effect of OSA screening practices on perioperative and longer-term health care costs, health care utilization and costs were compared between patients with OSA and matched patients without OSA in the 30 days post-bariatric surgery, as well as in the 1 year post-bariatric surgery. The Ontario Bariatric Registry (OBR) linked to the ICES health administrative databases were used. A diagnosis of OSA was identified if recorded in the OBR at time of initial bariatric consultation, or if recorded in ICES databases from the bariatric surgery admission records. Costs were calculated based on the “Guidelines on Person-Level Costing Using Administrative Databases in Ontario” using ICES costing algorithms. The overall prevalence of OSA was 47% (95% CI 46% to 47%). Total health care costs per patient, in the 30-day post-operative period, were 1% lower (95% CI 1% to 1%, p < 0.001) in patients with OSA compared to matched patients without OSA. Similarly, at 1 year postbariatric surgery, total health care costs per patient, were 1% lower (95% CI 1% to 1%, p < 0.001) in patients with OSA compared to matched patients without OSA. At 30 days and 1 year, this difference was driven by lower hospitalization-related costs. OSA screening practices at surgical centers in our network led to similar rates of OSA detection as reported in the literature. However, the literature suggests that screening practices lead to missed OSA diagnoses. Further study is required to understand the reduced post-bariatric surgery costs in patients with OSA compared to matched controls without OSA; and, we postulate that missed OSA diagnoses may be a contributor.