RESUMEN
The prevalence of insomnia is particularly high in old age. Sleep disturbances and impaired daytime functioning reflected in mood swings and concentration difficulties are often accompanied by other mental disorders such as depression. The objective of this article is to shed light on the role of insomnia in the context of frequent comorbidities in middle and old age. The focus is on the identification of linkage points between insomnia and associated diseases on a neurobiological level; however, possible distinguishing features are also named and deliberations on cognitive behavioral aspects and integrative theories, such as the hyperarousal theory are discussed. In order to provide an outlook for future research opportunities, the UK Biobank is presented as a promising resource of long-term data. Finally, the contents of the preceding deliberations are critically reflected and practical implications for the treatment of older patients with insomnia are derived.