O018 A 10 year follow-up of positive Multiple Sleep Latency Tests in a tertiary centre

Abstract Background There are limited robust population prevalence data and the natural history of central hypersomnolence disorders in Australia. We conducted a retrospective chart review multiple sleep latency tests (MSLTs) an Australian Sleep unit reviewed clinical outcomes over time, response to treatment duration follow-up. Methods 517 MSLTs were extracted from metropolitan hospital’s database between 2011 2021; 215 positive. Data overnight polysomnography (PSG), electronic medical records. The results analysed using t-test linear regression models. Results mean age was 36.7 years 58% female. 37 patients met criteria for type 1 or 2 narcolepsy, 157 idiopathic 21 alternative disorder. Of those with 84.6% commenced on medication. Modafinil most commonly prescribed first line At year, 48% narcolepsy group had complete partial success, compared 24% group. 3 years, 31% 12% reported success. 5 only 19% 6% described ongoing Discussion This study demonstrated much higher than expected. A significant number lost follow-up, predominantly 12 months, progressive losses subsequent years. reasons these unclear; however, would be important explore future studies.