Differences in polysomnographic (PSG) parameters between obese and non-obese patients with obstructive sleep apnea (OSA)

Background: Obesity is a main risk factor for OSA. Obese and non-obese patients represent different phenotypes of OSA. Objectives: To find PSG parameters that differentiate obese and non-obese OSA patients. Methods: Data of 381 OSA patients diagnosed with full PSG in accordance with the AASM were collected. Clinical and PSG parameters were evaluated. Results: Among 381 patients, 236 were obese (F 30%, mean age 58.0±11.2 years, mean BMI 37.5±6.8 kg/m2) and 145 non-obese (F 26%, mean age 60.0±13.9 years, mean BMI 26.5±2.4 kg/m2. Obese patients had significantly higher (p Conclusions: Obesity makes OSA more severe not only when expressed by higher AHI but also by oxygenation parameters. Average apneas durations do not differ between the two groups. Obesity increases not only obstructive but also mixed and central apneas. Back position increases the mostly AHI in obese patients in comparison to non-obese ones.