Characteristics of maintenance of wakefulness test in drug-naïve patients with narcolepsy type 1 and type 2, and relationship with other measures of sleepiness

MWT mSL is reduced in drug-naive narcolepsy, more severely in NT1 than in NT2. However, a minority of patients show normal MWT results. MSLT, MWT, and ESS measure different aspects of sleepiness in narcolepsy, and none can be considered a comprehensive measure of its severity. Statement of Significance This observational study explored the characteristics of maintenance of wakefulness test (MWT) in 97 drug-naïve patients with narcolepsy type 1 (NT1) and type 2 (NT2) at diagnosis. MWT mean sleep latency was lower in NT1 than in NT2. Unexpectedly, a minority of patients, both NT1 and NT2, managed to resist >30 min (n = 15) and up to 40 min (n = 8). MWT results showed moderate correlation with Epworth sleepiness scale and with multiple sleep latency test results, with no correlations with other clinical and neurophysiological markers. These findings define the performance of patients with drug-naïve narcolepsy on MWT and highlight the heterogeneity of NT1 and NT2 in terms of sleepiness assessed with different tools.