The Natural History of Mental Disorder in Old Age

Our classification of the mental disorders of later life, which are becoming a social and medical problem of increasing magnitude, is still based upon the views of the great descriptive psychiatrists of half a century ago. Most of the classical accounts of mental disorder of old age (Kraepelin, 1909; Bleuler, 1916) confine themselves to the pre-senile, senile and arteriosclerotic psychoses. Their writers evidently regarded other illnesses as numerically insignificant in relation to these degenerative disorders peculiar to old age. Cases with a predominantly depressive or paranoid picture or with clouding of consciousness alone were described in these old accounts, but were attributed to an underlying cerebral illness, either of senile or arteriosclerotic type. It is consequently a long-established practice when such symptoms appear for the first time in old age, or occur in senescence after prolonged remission, to search for neurological signs, or for some evidence of a decline in intellectual efficiency which might account for the illness in terms of organic disease of the brain. Weight is thus often given to clinical findings of a quite subtle character, or the results of “deterioration tests” whose value in the early diagnosis of degenerative processes in the brain is unproven, form the basis of conclusions of doubtful validity.