Background: Insomnia is the most prevalent sleep disorder. Chronic insomnia affects about 10% of the adult population.
Material and method: This review is based on the authors' experience, as well as articles identified through non-systematic searches in Pubmed.
Results: Insomnia is characterized by problems with falling asleep, difficulty maintaining sleep, waking up to early and/or poor sleep quality. The diagnosis implies that the problem causes some type of daytime impairment. Insomnia is divided into several different subtypes. Recent studies indicate that insomnia is an independent risk factor for sick leave and disability pension. Non-pharmacological treatment, i.e. stimulus control and sleep restriction yields better outcome than hypnotics, particularly on a long-term basis.
Interpretation: Insomnia is highly prevalent, and non-pharmacological therapy is the best documented treatment.