RT Journal Article SR Electronic T1 Anthropometric, sleep and clinical characteristics of patients with obesity hypoventilation syndrome in comparison with obese obstructive sleep apnoea syndrome patients and controls JF ERJ Open Research JO erjor FD European Respiratory Society SP P94 DO 10.1183/23120541.sleepandbreathing-2017.P94 VO 3 IS suppl 1 A1 Rodopi Sotiropoulou A1 Evangelia Nena A1 Christina Nikolaou A1 Afroditi Rousanidou A1 Ioannis Katrachouras A1 Andrea Kizi A1 Athanasios Voulgaris A1 Maria Xanthoudaki A1 Marios Froudarakis A1 Paschalis Steiropoulos YR 2017 UL http://openres.ersjournals.com/content/3/suppl_1/P94.abstract AB Aim of the study was to evaluate anthropometric, clinical and sleep characteristics of Obesity Hypoventilation Syndrome (OHS) patients, in comparison to obese eucapnic Obstructive Sleep Apnea Syndrome (OSAS) patients and controls.Methods Included were 942 consecutive subjects with BMI≥30kg/m2(69.9% males, age 54.9±11.9 years), examined with polysomnography (PSG), due to suspected OSAS. All had undergone pulmonary function testing and ABGs examination and had completed the Epworth Sleepiness Scale (ESS) and Athens Insomnia Scale (AIS) for sleepiness and insomnia assessment, respectively. They were categorized as follows: OHS patients (n=177), obese, eucapnic OSAS patients (AHI≥5/h, n=615), and obese controls with AHI<5/h (n=150).Results OHS patients had the highest BMI (p<0.001) and neck circumference measurements (p<0.001), but no difference was observed in other anthropometrics. Differences were observed in FVC, FEV1,SpO2, PaO2, PaCO2and HCO3values in awake (p<0.001 for all). PSG revealed a lower percentage of REM sleep (p=0.041) and a shorter REM latency (p=0.033) in OHS patients. AHI, ODI, minSpO2and averSpO2during sleep were more impaired in OHS patients (p<0.001). A higher prevalence of insomnia was observed in OHS (84.2%), followed by OSAS (70.8%) and controls (55.2%), p=0.041. Likewise, prevalence of daytime sleepiness was higher in OHS (59.2%) followed by OSAS patients (45.5%) and controls (32%), p<0.001.Conclusions OHS patients were more obese, differed significantly in several sleep characteristics and reported insomnia and daytime sleepiness more frequently, compared with obese OSAS patients and controls.