Prevalence of sleep-disordered breathing in Japanese medical students based on type-3 out-of-center sleep test

Sleep Med. 2018 Jan;41:9-14. doi: 10.1016/j.sleep.2017.09.023. Epub 2017 Oct 12.


Background: Sleep-disordered breathing (SDB), especially obstructive sleep apnea disorder (OSA), is thought to mainly affect men over the age of 40. Following findings that Asian people are more likely to experience severe OSA, regardless of obesity, we investigated the prevalence of SDB and OSA in a larger sample and in more younger age groups than those described in previous reports.

Methods: Between 2011 and 2016, 487 medical students (358 males, mean age 24.8 ± 1.9 years; 129 females: mean age 23.8 ± 1.6 years) underwent an out-of-center sleep test using a type-3 portable monitor. The results were analyzed visually.

Results: The mean ± standard deviation of the respiratory event index (REI: events/hour of monitoring) was 5.4 ± 6.7 (6.7 ± 7.5 in male participants, 2.6 ± 2.1 in female participants). There were 170 participants (36.6%) with an REI≥5, including 158 male participants (46.9%) and 12 female participants (9.1%). SDB or undefined OSA with low REI (15 > REI≥5) was observed in 141 participants (30.4%), defined OSA with moderate REI (30 > REI≥15) in 19 participants (4.1%), and defined OSA with high REI (REI≥30) in 10 participants (2.2%). Among the male students, 129 had low REI (38.3%), 19 had moderate REI (5.6%), and 10 had high REI (3.0%). All female participants with OSA events (9.4%) had a low REI.

Conclusions: The prevalence of OSA in Japanese young adults, especially males under 30 years old, is similar or even higher than that in older age groups described previously. Thus, an aggressive sleep study for SDB might be necessary for the younger generation in the Asian population.

Keywords: Obstructive sleep apnea; Out-of-center sleep test; Prevalence; Respiratory event index; Young adult.

MeSH terms

  • Adult
  • Asian People*
  • Female
  • Humans
  • Japan / epidemiology
  • Male
  • Polysomnography / instrumentation
  • Polysomnography / methods*
  • Prevalence
  • Risk Factors
  • Sleep Apnea, Obstructive / epidemiology*
  • Students, Medical / statistics & numerical data*
  • Young Adult