Sleep–wake disorders.

Abstract

In the 11th revision of the International Classification of Diseases World Health Organization [WHO], 2023), sleep-wake disorders have been unified in a new and separate chapter. This innovation corrects the inaccurate and fragmented distribution of these disorders in the 10th revision of the ICD (ICD-10), in which sleep-wake disorders were distributed across several chapters. In the ICD-10, so-called "nonorganic" sleep disorders were included in the chapter on mental and behavioral disorders, whereas most of the "organic" sleep disorders were included in the chapter on diseases of the nervous system. Other categories included in the ICD-11 chapter on sleep-wake disorders had previously been classified in the ICD-10 chapters on endocrine, nutritional, and metabolic diseases; diseases of the respiratory system; certain conditions originating in the perinatal period; and symptoms, signs, and abnormal clinical and laboratory findings, not elsewhere classified.The ICD-11 resolves the outdated mind-body, nonorganic-organic split inherent in the ICD-10. Many sleep-wake disorders comprise both physiological and psychological/behavioral components; they are neither strictly mental disorders nor medical conditions. Forced compartmentalization of these disorders into one or the other category resulted in misleading and inaccurate inferences regarding the nature of these conditions, with potentially adverse effects on treatment. The ICD-11 reflects an integrated biopsychosocial conceptualization of