Daytime sleepiness in an adult, Finnish population

Hublin C, Kaprio J, Partinen M, Heikkilä K, Koskenvuo M (Departments of Psychiatry and Neurology and the Department of Public Health (The Finnish Twin Cohort), University of Helsinki, Helsinki; and the Department of Public Health, University of Turku, Turku; Finland). Daytime sleepiness in an adult, Finnish population. J Intern Med 1996; 239: 417–23. Objectives. To investigate the prevalence of and the factors associated with daytime sleepiness occurring every or almost every day. Design. A cross‐sectional, questionnaire survey. Subjects. A total of 11354 adults (aged 33–60 years) representative of the Finnish population. Main outcome measures. Frequency of daytime sleepiness, naps and sleep attacks; occurrence of emotion‐associated muscle weakness, sleep debt, insomnia, sleep apnoeas and type of snoring; Beck Depression Inventory score; and the use of hypnotics and tranquillisers. Results. A total of 11.0% of women and 6.7% of men suffered from daytime sleepiness every or almost every day. Amongst those with sleepiness ( n = 1026) 19.5% of women and 42.3% of men reported snoring 3 nights per week, 25% had scores suggesting moderate to severe depression, 11% used hypnotics or tranquilizers on more than 180 days per year, and 9% reported insufficient sleep. Insomnia at least every other day was reported by 20.7% of women and by 28.6% of men. Amongst those with sleepiness, narcolepsy was found in 0.3%, with the diagnosis confirmed in a sleep laboratory evaluation. Conclusions. Daytime sleepiness occurring daily or almost daily is most often associated with depression, insomnia and sleep‐disordered breathing. In most cases, indications of the cause of sleepiness can be obtained by using simple screening questions.