Psychomotor slowness is associated with self-reported sleep duration among the general population
Short and long self-reported sleep durations have been found to be associated with several seemingly disparate health risks and impaired functional abilities, including cognitive functioning. The role of long sleep is especially poorly understood in this context. Psychomotor slowness, shown to have analogous associations with cognitive performance and health risks as self-reported long sleep duration, has not been studied together with sleep duration in epidemiological settings. We hypothesized that self-reported habitual sleep duration, especially long sleep, is associated with slow psychomotor reaction time, and that this association is independent of vigilance-related factors. The hypothesis was tested in a sample of 5352 individuals, representing the general adult population. We found a U-shaped association between self-reported sleep duration and psychomotor speed, which prevailed even after controlling for several pertinent confounders. This novel finding can be interpreted to mean that self-reported sleep duration, at least in the case of long sleep, is an indicator of bodily/brain integrity and, taken together with the results of cognitive epidemiology, may provide some new insights into the mechanisms underlying the associations between habitual self-reported sleep duration, health risks and impaired functional abilities.
Document Type: Research Article
Affiliations: 1: National Institute for Health and Welfare, Department of Chronic Disease Prevention, Turku, Finland 2: Department of Health Sciences, Finnish Centre for Interdisciplinary Gerontology, University of Jyväskylä, Jyväskylä, Finland 3: Department of Psychology, University of Jyväskylä, Jyväskylä, Finland 4: Department of Geriatrics, School of Public Health and Clinical Nutrition, University of Kuopio, Kuopio, Finland 5: National Institute for Health and Welfare, Department of Mental Health and Alcohol Research, Helsinki, Finland
Publication date: June 1, 2011