Psychiatric morbidity in the aged

Mental morbidity in the elderly comprises mainly affective disorders (manic depressive psychosis) and psycho-organic syndrome, delirium and dementia. Psychiatric disorder occurs with physical disorder or handicap and co-morbidity is the hall-mark of geriatric medicine. The prevalence rate is around 89/1000 population. The decreasing age at onset of depression over successive generations contributed by the 'unstable genes' is discussed. Factors affecting the 'quality ageing' are highlighted. Depression, mania and suicide behaviour in the elderly are detailed. Particular attention is drawn to 'vascular depression' resulting from cerebrovascular lesions affecting the striato-pallido-thalamo-cortico-pathways. Vascular depression is characterised by a low frequency of family history of mental disorder/suicide and anhedonia and increased functional disability. Subsyndomal depression is a fairly common occurrence. Anxiety disorders in the elderly though uncommon need to be recognised. Late-onset schizophrenia and somatic hallucinosis are referred to.