Abstract
The association between depression, suicide, and unnatural death is well established, but the association between depression and premature death due to natural causes has yet to be unequivocally established. This thesis sets out to explore whether or not premature mortality is part of the natural history of a depressive illness; to establish the period of highest risk, and to discriminate between death following endogenous and reactive depressive illness. A cohort was available for study consisting of all depressed patients referred to the psychiatric service in two catchment areas. These patients were followed for 24 years, and with the co-operation of the Office of Population Census and Surveys, copies of the death certificate of those who died were obtained by the researcher. A control population was prepared for statistical analysis using the England and Wales mortality Tables which are published annually. Statistically significant premature mortality was found throughout the 24 year period from both natural and unnatural causes. Death was found to occur predominantly in the early years after referral and the diagnosis of endogenous depression was found to incur the greater mortality. The discussion speculated on the most likely mechanisms mediating between depression and death. Possible improvements in the design were discussed and further research highlighted. This thesis by establishing that premature mortality is part of the natural history of depressive illness, has contributed to scientific knowledge.