0762 Diagnosis Of Pediatric Narcolepsy : Review Of PSG/MSLT At A Single Institution

Abstract

Excessive daytime sleepiness is a common symptom in children with a wide differential diagnosis. Although narcolepsy may present during pediatric years, there is often a delay in diagnosis. In adults, a polysomnogram (PSG) followed by a multiple sleep latency test (MSLT) is used to diagnose narcolepsy. There are less published data regarding the use of this test in pediatric patients. The purpose of this study is to assess PSG/MSLT variables in the pediatric population presenting with excessive daytime sleepiness and to evaluate additional variables on the PSG which may be associated with narcolepsy. This IRB-approved, retrospective chart review evaluated data from all patients who completed a PSG and MSLT from January 2012 to June 2018 at the Nemours/ du Pont Hospital for Children. Demographics, sleep study data, and clinical symptoms were reviewed for eligible patients. T-tests not assuming equal variance were used to compare the results between patients with and without narcolepsy. 183 patients completed a PSG and MSLT during the 6.5-year testing timeframe (mean age 12.6 years, 53% male, 52% Caucasian). Of these, 39 patients (21%) were diagnosed with narcolepsy. There were no demographic differences between patients diagnosed with narcolepsy and those not diagnosed with narcolepsy. On the MSLT, patients with narcolepsy showed a significantly lower mean sleep latency and more sleep-onset REM periods (SOREMPs) than patients without narcolepsy (mean sleep latency: 3.21 vs. 11.15 minutes, P <0.001; SOREMPs 2.94 vs. 0.37, P <0.001). On the PSG, there were no differences in measurements of sleep-disordered breathing between the two groups. However, patients with narcolepsy showed a higher appearance of periodic limb movements (PLMs) and higher PLM index (appearance of PLMs: 53.19% vs.33.59% P = 0.02; PLM Index: 6.26 vs. 2.50, P= 0.03). The MSLT is a valid test for diagnosing pediatric narcolepsy. Additionally, the overnight polysomnogram may reveal important clues about a diagnosis of narcolepsy. We found that patients with narcolepsy showed increased periodic limb movements compared to patients without narcolepsy. None