TY - JOUR T1 - Obstructive sleep apnoea (OSA) in non-obese patients: phenotyping an East Indian cohort and response to CPAP treatment JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.sleepandbreathing-2017.P44 VL - 3 IS - suppl 1 SP - P44 AU - Angshuman Mukherjee Y1 - 2017/04/01 UR - http://openres.ersjournals.com/content/3/suppl_1/P44.abstract N2 - Introduction OSA in non obese is a well recognised but less characterised phenotype especially in an Indian perspective. This particular study looks at demographics & response to treatment in this cohort.Material & Method We have studied 110 consecutive patients with OSA in our sleep lab from January 2015 to December 2015. Data of 53 non obese overweight (BMI ≤30 kg/m2) patients having severe OSA (AHI≥ 30) were compared retrospectively to 57 obese (BMI≥ 30) age matched controls & analysed by Statistical ‘R’ software.Results The non obese group is predominantly male (90.56%) whereas the obese group consists of 40.35% females. The mean age is around 49 years in both the group. Obese are more current smoker (59.65%). The non obese have lesser mean AHI (36.8/hr) than obese (47.2/hr). Non Compliance to CPAP is less in Non Obese (35.85%) compared to obese (50.88%). On CPAP use, reduction in Mean ESS score (t stat value -8.53 compare to -4.86) & Mean STOP BANG score (t stat value -8.63 compare to -6.87) were significant in both the groups but the reduction is greater in non obese group; (p<0.01). The Non obese group consists of more diabetics (49.06%) & hypertensive (75.47%) but this is not statistically significant.Conclusion Non obese overweight patients with OSA have significant improvement with auto CPAP and also better compliance to obese counterparts. There is a trend to more metabolic complication (diabetes & hypertensive) in the non obese group but this does not reach statistical significance. ER -