0586 Positive Airway Pressure Changes in Patients with Obstructive Sleep Apnea After Weight Reduction Surgery

Abstract Introduction Obesity is a modifiable risk factor for obstructive sleep apnea (OSA). Weight management interventions have been shown to reduce OSA symptoms and severity for some patients. This retrospective analysis aimed to evaluate the impact of weight reduction surgery or procedure (WRS/P) on pressure changes in positive airway pressure (PAP) treated patients as a proxy for changes in OSA severity following surgery. Methods We analyzed administrative claims data from 2015 to 2021 of adult (≥18 years) OSA patients linked to PAP device data. The date on which the first ICD-10/9 or CPT code appeared for a WRS/P was the index date. Inclusion criteria were a categorical body mass index (BMI) ≥30 kg/m2 at baseline, at least 1 year of insurance coverage pre-index, and a minimum of 1 year of PAP therapy data post-index. Changes in PAP pressure were assessed as the difference between median PAP pressure 1 month pre-index and the most recent pressure post-index date. Only categorical BMI is coded in claims, so changes in BMI category following WRS/P were assessed using the difference between categorical midpoints. Results A total of 17,284 OSA patients underwent WRS/P (mean age 45.6 years; 74.7% female). Patients were categorized based on their pre WRS/P BMI (≥30 - 35, ≥35 - 40, ≥40 - 45, ≥45 - 50, ≥50 - 60, and ≥60 kg/m2). The average baseline apnea-hypopnea index (AHI) was 16.9, 18.2, 19.9, 23.4, 25.1, and 27.0 events/h respectively. After WRS/P the average decrease in BMI was 3.3, 5.7, 6.8, 8.1, 10.3, and 13.0 kg/m2; and the average decrease in the median PAP pressure was 0.8, 0.9, 1.0, 1.3, 1.3, and 1.3 cm H2O respectively. Conclusion Patients with the highest baseline BMIs experienced the most weight loss after WRS/P. These individuals also had the greatest reductions in PAP pressures following surgery. Using PAP pressure as a proxy for OSA severity, in absence of post-surgery sleep testing, our findings suggest that patients with higher baseline BMIs are likely to achieve the most substantial, albeit not complete, reductions in OSA severity, compared to those with lower baseline BMI, after undergoing WRS/P. Support (if any) ResMed