Historical development of psychiatric classification and mental illness

Psychiatric classification has been developing for over 100 years and there are now over 400 diagnoses available. Dementia and adjustment disorder were the only diagnosis available for older adults until a number of papers published between 1944 and 1955 demonstrated the relevance of functional mental illness for older adults. It was not until 1987 that the Diagnostic and Statistical Manual published by the American Psychiatric Association included an option to diagnose schizophrenia in the over 45s. This paper describes the historical development of psychiatric classification and discusses how this has potentially influenced ageist attitudes to older people, with particular reference to schizophrenia and dementia. Nurses are encouraged to reflect on their own attitudes in light of this discussion as to how medical frameworks for understanding mental illness may have influenced personal beliefs, particularly ageist beliefs about older adults.