Restless legs symptoms with sleepiness in relation to mortality: 20-year follow-up study of a middle-aged Swedish population.

Aim: The aim of the present study was to investigate restless legs symptoms with concomitant daytime sleepiness as a risk factor for mortality in a middle-aged population.

Methods: A cohort of 5102 subjects aged 30-65 years in mid-Sweden who responded to a postal questionnaire in 1983 was followed up. The questionnaire included questions about restless legs symptoms, daytime sleepiness, demographic and lifestyle variables, sleep habits, medical conditions and depression. Mortality data for the period 1983-2003 were collected and death certificates were available for all the 657 responders who died during the follow-up period.

Results: Restless legs symptoms with daytime sleepiness was reported by 10.3% and was associated with shorter night sleep time, several health problems and depression. During the follow-up period 379 men (21.6%) and 278 women (15.5%) died. A multivariate model adjusted for age, short night sleep time, lifestyle factors, medical conditions and depression showed that women reporting restless legs symptoms with daytime sleepiness had an excess mortality compared to women without restless legs symptoms and daytime sleepiness (hazard ratios, 1.85; 95% confidence interval, 1.20-2.85; P = 0.005). No influence on mortality risk was found in men reporting restless legs symptoms with daytime sleepiness.

Conclusions: The occurrence of restless legs symptoms with daytime sleepiness in middle-aged women is associated with increased mortality risk.