In a systematic review and meta-analysis of studies on changes in night sleep measured by polysomnography (PSG) in these patients, the study researchers found that patients with narcolepsy, especially type 1 narcolepsy (with cataplexy), have poor night sleep.
The authors of the study included 65 case-control studies in which narcolepsy patients were compared with healthy controls (HCs) who reported differences in PSG-measured night sleep parameters between the groups. They also included 41 studies in patients with type 1 (NT1) and type 2 (NT2) narcolepsy, narcolepsy patients with and without rapid eye movement sleep disorder (RBD) (n = 4), and those who were positive or negative for human leukocyte antigen , were compared (HLA) DQB1 * 06: 02 (n = 3).
Compared to healthy controls, narcolepsy patients had a significantly higher total sleep time (TST), wake-up time after the onset of sleep (WASO) (SMD = 0.670), awakening numbers (AWN) (SMD = 1.501), stage shift (SS) (SMD =) 0.937), apnea Hypopnea Index (AHI) (SMD = 0.253), Periodic Limb Movement Index (PLMI) (SMD = 1.032), and N1 Percentage (SMD = 1.136).
Narcolepsy patients had a significantly reduced sleep latency (SL) (standardized mean difference (SMD) = -0.954), sleep efficiency (SE) (SMD = -0.250), N2 percentage (SMD = -0.811), slow-wave sleep (SWS) (SMD = -0.230), rapid sleep latency with eye movements (REML) (SMD = -1.320) compared to healthy controls.
A publication bias was found for the differences in TST (initially no significant difference was found), SL, N1, SWS, REML and PLMI between groups. After adjusting for the publication bias, the study researchers identified a statistically significant increase in TST (SMD = 0.236) in narcolepsy patients compared to HCs, while the direction of change for the other measures remained consistent.
The meta-analysis revealed a significantly reduced rate of cyclical change patterns (CAP) (SMD = -1.115), A1 index (SMD = -1.022), A1 percentage (SMD = -0.446) and A2 index (SMD = -0.431) Narcolepsy patients compared to HCs.
The moderator analysis showed that an increased percentage of male narcolepsy patients in studies was significantly associated with a decreased AWN (point estimate = -2.496, P = 0.003) compared to HCs. The decreased mean age in narcolepsy patients compared to HCs was significantly associated with AWN (point estimate = -0.023, P = 0.031) and WASO (point estimate = -0.022, P = 0.019).
After performing the Egger test, the subgroup analysis showed a significant reduction in TST, SL, SE, REM percentage and REML as well as a significant increase in WASO, AWN, SS, AHI and PLMI in NT1 patients compared to NT2 patients.
A meta-regression analysis also found that a decreased mean age in various studies was significantly associated with an increased AWN (point estimate = -0.023, P = 0.031) and WASO (point estimate = -0.022, P = 0.019) in narcolepsy patients compared to HCs. A supplementary subgroup analysis also showed that the magnitudes of increased AWN (SMD = 1.855) and WASO (SMD = 1.174) in children and adolescent narcolepsy patients (compared to HCs) compared to those (AWN, SMD = 1.288; WASO,) more obvious were. SMD = 0.547) in adult narcolepsy patients.
The study researchers also found a statistically significant increase in TST in narcolepsy patients compared to HCs in studies without patients taking psychoactive drugs. Narcolepsy patients showed a significant decrease in REML compared to HCs, which was more evident in studies without patients taking psychoactive drugs.
Limitations of the review included the inability to evaluate the effects of various psychiatric conditions or drugs on PSG changes in narcolepsy and the exclusion of studies that used “clinical controls”.
Zhang Y., Ren R., Yang L. et al. Nocturnal polysomnographic features of narcolepsy: a systematic review and meta-analysis. Sleep medicine reviews. Published online April 5, 2021. doi: 10.1016 / j.smrv.2021.101488
This article originally appeared on Psychiatry Advisor