Most patients with hypersomnia, defined as a total sleep time of at least 19 hours, are mostly young, have a younger age with excessive daytime sleepiness (EDS) and have normal sleep architecture and continuity according to study results published in Sleep.
Previous studies reported that hypersomnolence, defined by EDS or excessive amount of sleep (EQS), is associated with increased morbidity. The aim of the current study was to investigate the clinical and polysomnographic properties of EQS and EDS during the extended polysomnographic recording.
This study included 266 participants (201 women; mean age 26.5 years) who had completed the polysomnography recording followed by a modified Multiple Sleep Latency Test (mMSLT). The mMSLT included 5 naps every 2 hours from 9 a.m. to 5 p.m., with participants being awakened after 1 minute of sleep. All of them then underwent a 32 hour bed rest polysomnography recording. The mMSLT and 32-hour bed rest monitoring included both electroencephalogram, electrooculogram, and submental electromyography.
The study participants were divided into 4 groups: total bed rest sleep time of less than 19 hours compared to at least 19 hours and mean sleep latency (MSL) of no more than 8 compared to more than 8 minutes. Participants were also divided into three groups: isolated EDS, isolated EQS, or complaint about both EDS and EQS.
Overall, 90.15 percent of participants had complaints about isolated EDS, 79.76 percent had complaints about EQS, and 71.71 percent said they had both conditions. The MSL was no more than 8 minutes in 132 (49.62%) participants and 8 to 10 minutes in 36 (13.53%) participants.
Compared to patients with a total bed rest sleep time of less than 19 hours, those with a sleep duration of at least 19 hours were younger, had an EDS onset at a younger age, and a higher sleep efficiency on polysomnography was recorded in the night before bed rest was recorded carried out. and shorter MSL on mMSLT.
Compared to participants with an MSL of more than 8 minutes in the mMSLT, those with an MSL of no more than 8 minutes reported less frequently night EQS of at least 9 hours and 24 hour EQS of at least 11 hours on weekdays and weekends higher sleep efficiency, longer sleep duration, and higher percentage of hypersomnia.
A total of 207 patients reported isolated EDS and / or hypersomnia, 5 of whom met the diagnostic criteria for narcolepsy type 2. 71 of the remaining 202 participants met the criteria for idiopathic hypersomnia.
Limitations of this study included selection biases, a lack of information about participants’ circadian preferences, and the exclusion of participants with severe forms of comorbidities, including BMI, depressive symptoms, and sleep apnea.
“Sleep duration and EDS should be quantified using self-reported and objective measures in a controlled process to distinguish late risers, patients with hypersomnia and patients with idiopathic hypersomnia,” the study’s researchers concluded.
Evangelista E., Rassu AL, Barateau L. et al. Features related to hypersomnia and excessive daytime sleepiness identified by expanded polysomnographic records. Sleep. Published online on November 29, 2020. doi: 10.1093 / sleep / zsaa264