Mia Strohm, Amro Daboul, Anne Obst, Antoine Weihs, Chia-Jung Busch, Thomas Bremert, Jochen Fanghänel, Tatyana Ivanovska, Ingo Fietze, Thomas Penzel, Ralf Ewert, Markus Krüger

• Background: This study examines the relationship between obstructive sleep apnea severity, sleep position, and body weight, particularly focusing on the negative impact of sleeping in a supine position combined with being overweight in a population-based sample. Methods: The Apnea-Hypopnea Index (AHI) was utilized as a marker of OSA severity and sleep position from a standardized overnight polysomnography. Participants were categorized by body mass index (BMI) (kg/m 2 ) into normal weight/underweight (<25) and overweight (≥25). Results and Conclusions: The results indicated a higher mean Apnea-Hypopnea Index for those sleeping in the supine position compared to other positions, with overweight individuals experiencing a proportionally greater impact from sleep position than their normal-weight counterparts.