Background: To examine the association between sleep-related factors and measured and self-reported mobility in a representative sample of older adults.
Methods: This study included 2,825 men and women aged 55 years and older participating in a cross-sectional representative population-based Health 2000 Survey in Finland. Sleep duration, insomnia-related symptoms, and fatigue were inquired. Maximal walking speed was measured, and mobility limitation was defined as self-reported difficulties in walking 500 m or stair climbing.
Results: Insomnia-related symptoms and fatigue were prevalent among persons aged 65 years and older in particular. After adjusting for lifestyle factors and diseases, longer sleep (>/=9 hours) was associated with a decreased walking speed in women aged 65 or more years (p = .04) and shorter sleep (</=6 hours) with a higher odds for mobility limitation in women aged 65 or more years (odds ratio [OR] = 1.68, 95% confidence interval [CI] = 1.02-2.75) and in men aged 55-64 years (OR = 3.62, 95% CI = 1.40-9.37) compared with those having a mid-range sleep duration. Sleeping disorders or insomnia was independently associated with both decreased walking speed and mobility limitation in men aged 55 or more years but only with mobility limitation in women aged 65 or more years. Of the sleep-related daytime consequences, "weakness or tiredness" was associated with a decreased walking speed and a higher odds for mobility limitation both in men and in women aged 55 or more years.
Conclusions: Several sleep-related factors, such as sleep duration, insomnia-related symptoms, and fatigue, are associated with measured and self-reported mobility outcomes.