Correlations between subjective and objective features of nocturnal sleep and excessive diurnal sleepiness in patients with narcolepsy

Abstract

-Objective: To determine the correlations between excessive daytime sleepiness (EDS), assessed by the Epworth sleepiness scale (ESS), and the multiple sleep latency test (MSLT) and nocturnal sleep architecture features, clinical symptoms of narcolepsy (CSN) and subjective sleep quality (SSQ) in patients with narcolepsy. Method: Twenty three untreated patients were studied and compared with a matched control group. Diagnosis of narcolepsy was carried out employing a clinical interview, a polysomnographic (PSG) record, and an MSLT. Results: Subjective number of awakenings was the SSQ indicator that best correlated with EDS (ESS and MSLT). Regarding clinical features, diurnal tiredness and sleep paralysis correlated with ESS values. Increase in ESS was related with decrease in total sleep time, SWS, and sleep onset latency. On the other hand, increase in MSLT was related with decrease in SWS. Conclusion: These data suggest that EDS in patients with narcolepsy could be impaired by disturbed nocturnal sleep.KEy WORDS: narcolepsy, clinical symptoms, subjective sleep quality, sleep architecture, Epworth sleepiness scale, multiple sleep latency test, excessive daytime sleepiness. Correlação entre as características objetivas e subjetivas do sono noturno e a hipersonolência diurna em pacientes narcolepticosResumo -Objetivo: Determinar as correlações entre hipersonolência, avaliada pela escala de sonolência Epworth (ESE) e o teste múltiplo de latência do sono (TMLS) com a arquitetura do sono (AS), sintomas e qualidade subjetiva do sono em pacientes narcolepticos. Método: Comparou-se um grupo de vinte e tres pacientes narcolepticos sem tratamento com grupo controle. O diagnóstico de narcolepsia foi realizado por uma entrevista clinica, polissonografia e o TMLS. Resultados: O número subjetivo de despertares foi o indicador com maior relação com a hipersonolência, o cansaço diurno e a paralisia do sono também foi correlacionados com a ESE.O aumento do índice na ESE foi correlacionado com uma diminuição do tempo total do sono, no sono de ondas lentas (SOL) e com a latência para o início do sono. O incremento na TMLS foi relacionado com diminuição do SOL. Conclusão: Os dados sugerem que a hipersonolência diurna em pacientes portadores de narcolepsia pode se correlacionar com as alterações da arquitetura do sono noturno. PALAVRAS-CHAVE: sintoma clínico de narcolepsia, qualidade subjetiva do sono, teste múltiplo de latência do sono, hipersonolência.

Disrupted Nighttime Sleep in Narcolepsy

“…Thus, a total of 21 studies met the inclusion criteria ( Table 2). 14,[19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38] …”

“…PSG comparisons between patients with narcolepsy and normal controls with no history of sleep disorders consistently find that patients with narcolepsy experience frequent brief awakenings and arousals (e.g., excessive shifts to S1 sleep or wake from deeper sleep stages), therefore having more time spent in S1 sleep, an elevated WASO, and reduced sleep efficiency relative to normal controls ( Table 4 and Figure 2). 20,23,24,[26][27][28][29][30]32 These nighttime sleep patterns are present whether or not patients are receiving stimulant medications, 20,22,32 including in drug-naïve patients with narcolepsy, 30 albeit in a small sample (N = 8), as well as when compared with other sleep disorders. 32,36 These observations provide further support for an association between narcolepsy and DNS that is also independent of stimulant use, and although the studies do not identify underlying causes of DNS, several suggest an abnormality in non-REM (NREM) sleep as a possible mediator.…”

“…27,28,40,41 Despite the consistency of reports of DNS in narcolepsy, few studies have attempted to correlate DNS with narcolepsy's daytime symptoms. 24,26 Those that have, produced inconsistent results or found suggestive, but not completely persuasive, correlations between DNS and EDS.…”

“…24 Jiménez-Correa and colleagues compared patients with narcolepsy and healthy matched controls with no history of sleep disorders (n = 23 in each group) and found that patients with narcolepsy had a greater percent of S1 sleep (16.60% vs. 10.57%, respectively; p < 0.05) and S2 sleep (58.36% vs. 52.09%, respectively; p < 0.05), a significantly greater number of arousals (78.38 vs. 29.13, respectively; p < 0.05), and more awakenings lasting < 3 minutes (mean, 35.15 vs. 3.77, respectively; p < 0.05). 26 Using measures of daytime sleepiness (ESS, MSLT, subjective sleep quality) and other tools, investigators reported moderate correlations between EDS and DNS. Daytime sleepiness was associated with WASO and frequency of awakenings, and lower total sleep time, sleep efficacy, and percent of slow wave sleep.…”

“…Finally, studies have compared the nighttime sleep of patients with narcolepsy with the nighttime sleep of patients with , 23 Jiménez-Correa et al, 26 Mukai et al 30 other sleep disorders. 19,36 Baker et al found that patients with narcolepsy had more DNS than did patients with IH, characterized by more S1 sleep, greater WASO, and lower sleep efficiency.…”