0432 Estimating the Prevalence of Obesity Hypoventilation Syndrome in a Rural Appalachian Inpatient Cohort

Abstract

Abstract Introduction Patients with Obstructive Sleep Apnea (OSA) and concomitant Obesity Hypoventilation Syndrome (OHS) have been shown to have excess morbidity and mortality and higher healthcare expenditure when compared with patients with OSA only. Despite this, OHS is typically underdiagnosed and untreated. These effects may be more pronounced in rural Appalachian patients in whom rates of obesity, cardiovascular disease, metabolic disease, smoking, and COPD exceed the national average, yet poverty and challenging geography undermine access to healthcare. Methods Eligible patients from Sept 2019-Jan 2022 were evaluated for sleep disordered breathing under our hospital sleep medicine program. These patients were screened using high-resolution pulse oximetry, or a portable Type III sleep testing device, or both. Their data was recorded onto our program registry and retrospectively analyzed. Results Of 1676 hospitalized patients evaluated through our hospital sleep medicine program, we determined that 1345 (80.2%) of patients had a BMI >/=30 kg/m2. Of these patients, 823 (49.1%) had an arterial or venous blood gas collected during screening. Excluding patients with other potential causes for hypercapnia, 178 (10.6%) met criteria for OHS. 119 (66.8% of this subgroup) met criteria for OSA/OHS, while 33% did not have OSA (AHI/ ODI< 5). Patients with OSA/OHS overlap in our cohort typically had mild OSA. Conclusion When compared estimates in urban populations, our cohort is underrepresented. As such, many more patients with potential OHS and OSA/OHS overlap are discharged home without any treatment or plan for follow-up. One possible solution is suggested by the fact that only 49.1% of our initial cohort had an arterial or venous blood gas (ABG/VBG) collected during the admission. We recommend additional screening with serum bicarbonate and subsequent blood gases as part of an inpatient screening program for OSA/OHS. Early identification of these patients may facilitate early treatment while in-hospital and help reduce health disparity. Support (if any)