Consequences of chronic (primary) insomnia: Effects on performance, psychiatric and medical morbidity—An overview

Summary Question of the study   Chronic insomnia afflicts approximately 5 – 10 % of the adult population in Western industrialized countries. Insomnia may be secondary, i. e. triggered and/or maintained by psychiatric/organic illnesses or the intake of prescribed/illicit drugs. It can also occur as primary insomnia, due to a psychophysiological hyperarousal process.
This review article aims at analysing the literature on the consequences of chronic primary insomnia to delineate the sequelae of 'pure' insomnia with respect to performance and to psychiatric and medical morbidity.
Methods   Literature review.
Results Concerning aspects of performance, studies describing the effects of primary insomnia are scarce. Chronic primary insomnia does not seem to lead to increased daytime sleepiness, but rather to the opposite. Neuropsychological consequences seem to be only of a minor nature. No data exist that prove definitively that primary insomnia is accompanied by general psychosocial impairments. Studies dealing with the interplay between primary insomnia and psychiatric disorders, especially depressive disorders, have been published increasingly in recent years. Analysis of the pertinent literature indicates that patients with primary insomnia are at heightened risk of developing a depressive disorder.
With respect to medical morbidity, the picture is less clear: primary insomnia leads to a heightened utilization of health services and an increased frequency of diagnostic and therapeutic interventions, especially the intake of hypnotic drugs. There is no proof yet that primary insomnia is coupled with an increased frequency of cardiovascular diseases or a weakening of immune functions.