Periodic Leg Movements during Sleep in Japanese Community-dwelling Adults Based on the Assessments of Their Bed Partners

BACKGROUND: There is little known about epidemiologic evidence on periodic leg movements during sleep (PLMS) for the Japanese. The present study was a cross-sectional epidemiologic study to estimate the prevalence of PLMS and examine the associated factors of PLMS in Japanese community-dwelling adults. METHODS: The subjects were 884 with bed partners or bedroom mates of 1,889 Japanese adults aged 20 years and over randomly selected from the general population. The case ascertainment of PLMS was based on the assessments of their bed partners or bedroom mates using the Pittsburgh Sleep Quality Index. Multiple logistic regression analyses were used for investigating the associated factors. RESULTS: The age-adjusted prevalences (95% confidence interval) were 5.8% (4.7-6.8%) and 1.3% (0.8-1.9%) for 1 to 2-times, and 3-times or greater of PLMS per week during the preceding month, respectively. Those with PLMS were more likely to experience difficulty in initiating sleep, snore during sleep, be depressed, and suffer from peptic ulcer. Sex, age, difficulty in maintaining sleep, excessive daytime sleepiness, medication use to aid sleep, and any psychoactive substances (tobacco, alcohol, and caffeine) were not identified as significant associated factors of PLMS. CONCLUSIONS: The results suggest that the prevalence of PLMS in Japanese community-dwelling adults is not so high as those reported from Western countries, and that PLMS is correlated with some sleep and health disturbances.