Clinical and Polysomnographic Differences in Obese and Nonobese Patients with Obstructive Sleep Apnea

Abstract Background: Obstructive sleep apnea (OSA) is characterized by repeated episodes of upper airway obstruction during sleep, resulting in fragmented sleep and associated health risks. Objective: This retrospective study investigated the clinical and polysomnographic differences between obese and nonobese patients diagnosed with OSA. Methodology: A total of 210 patients underwent a Level 3 sleep study. Based on the apnea-hypopnea index (AHI), 180 patients with OSA were included in the study. Patients were categorized as obese (body mass index BMI ≥27.5) or nonobese (BMI <27.5). Clinical parameters, AHI, oxygen desaturation index (ODI), Epworth Sleepiness Scale (ESS), neck circumference, age, and gender were compared. Results: Obese patients had significantly higher AHI, ODI, ESS scores, and neck circumference than nonobese patients ( P < 0.05). Gender was associated with the severity of OSA only in the obese group. Age was not significantly associated with OSA severity in either group. Discussion: Obesity is strongly associated with more severe OSA and anatomical risk factors. Nonobese OSA patients also exhibited clinically relevant symptoms, suggesting distinct nonanatomical mechanisms. Conclusion: This study concludes that while obesity is linked to more severe OSA due to anatomical factors, non-obese patients also experience significant disease, highlighting the importance of individualized, phenotype-driven management strategies.