Restless legs syndrome and its correlation with other sleep problems in the general adult population of Japan

Abstract

The epidemiological study presented here was conducted to examine the association between sleep problems and restless legs syndrome (RLS) among a large sample taken from the general population of Japan. The presence of RLS was established by asking the subjects if they experienced a crawling sensation in their legs after going to bed. This survey was performed in June 2000, targeting a sample that was randomly selected from 300 communities throughout Japan. The questionnaire contained questions focusing on health consciousness, mental health, and sleep. A total of 26 705 participants completed the questionnaire. The prevalence of RLS was 3.0%, with a significant predominance in women. The prevalence of RLS increased significantly with advancing age. Multiple logistic regression analysis revealed that RLS was significantly associated with difficulty initiating sleep (odds ratio, OR = 2.58), excessive daytime sleepiness (OR = 2.28), difficulty maintaining sleep (OR = 1.71), non-restorative sleep (OR = 1.51), subjective insufficient sleep (OR = 1.36), and early morning awakening (OR = 1.21). These results suggest that the prevalence of RLS in Japan is lower than in northern European populations and that RLS is strongly associated with difficulty initiating sleep and excessive daytime sleepiness.

Prevalence of restless legs syndrome with pregnancy and the relationship with sleep disorders in the Japanese large population

“…This means that the estimated OR of DMS was not established. These results were quite similar to those of a study of the general Japanese population by Enomoto et al 14 In their study the OR with regard to RLS were DIS (2.58), EDS (2.28), DMS (1.71), SIS (1.36) and EMA (1.21). Manconi et al also pointed out an association with EDS.…”

“…This value is similar to previously reported values (1.06%, 12 1.5%, 13 and 3.0% 14 ) for the prevalence of RLS among the general population in Japan. It is known that the prevalence of RLS in Western countries is higher [15][16][17][18][19][20] (in the range of 5.5-14.3%) than that in other countries, including Asian countries [12][13][14][21][22][23][24] (in the range of 0.1% to 3.19%). Genetic differences were suggested 7,25,26 as a reason for this difference.…”

“…The four questions regarding RLS were formulated directly from the diagnostic criteria defined by the International RLS Study Group, 9 e.g. “Do you feel that an urge to move or unpleasant sensations begin or worsen during periods of rest or inactivity such as lying or sitting?” The respondents who answered all four questions with “sometimes”, “often”, or “always” were defined as having RLS to compare these data with other studies 11–14 …”

“…The respondents who answered all four questions with "sometimes", "often", or "always" were defined as having RLS to compare these data with other studies. [11][12][13][14]…”

Epidemiology of restless legs syndrome in the Iranian population

“…Nevertheless, difficulty in sleep initiation and repeated awakening during the night were the first and second most prevalent complaints, respectively, which was in accordance with a previous study in Japan showing a strong association of RLS with difficulty during sleep initiation. 26 About half of the patients reported that their symptoms usually began at bedtime, but 38.7% suffered from leg disturbance while awake throughout the day.…”