Late Breaking Abstract - Polysomnography and clinical characteristics of patients presenting to single sleep referral clinic-study over 6 years

Abstract

Introduction: Sleep disordered breathing (SDB) disorders are major cause of morbidity and mortality. We studied clinical characteristics and PSG correlation of SDB. Aim Objective and Methods: 1028 patients analysed who presented to our referral sleep clinic from September 2011 to April 2017. Mallampatti (MPT) and Epworth Sleepiness Scale (ESS) were scored. PSG’s were scored manually and revalidated by a single sleep specialist. Gender, BMI, ESS, MPT, snoring pattern, AHI, oxygen desaturation, arousal index and arrhythmias were recorded and analysed. Demographic and PSG differences in Indian and African patients was studied. Results: 1028 patients were studied. Mean BMI was 31.68. Mean ESS score was 11.5. Mean Arousal index was 48.821. Postural relation was present in 206 OSA patients. Atrial fibrillation (AF) was present in only 5 (0.5%) patients of OSA. 975 patients had OSA. Out of these 216 had upper airway resistance syndrome (UARS) with OSA. 25 had UARS only. 1 had narcolepsy. 6 had complex sleep apnoea. 2 had mixed apnoea. 6 had primary snoring. 1 patient had idiopathic hypersomnia. 4 had sleep onset and maintenance insomnia without respiratory disturbance. Only 5 had normal study. AHI of >30/hr was found in 48% of Africans vs 58% of Indians. SWS was very short to absent in 49% and protective in 23% of Africans vs 34% and 29% of Indians respectively. Conclusion: Almost 60% SDB patients had severe OSA and almost 35% of all SDB patients had an AHI >60/hr. AF in our series is very uncommon present in only 0.5 % patients of SDB. Indians had relatively higher OSA severity than African patients. Also MPT and ESS were significantly higher among Indians