Pharmacological prevention of suicidal behaviour

Abstract

The number of hospital admissions following an episode of deliberate self harm has been increasing steadily over the past two decades and hospitals in England and Wales now provide care for some 100,000 cases of deliberate non-fatal self-poisoning per year. Indeed in younger women self-poisoning is the commonest cause of emergency admission to a medical ward. The rate of actual suicide has not changed very much although the unreliable nature of suicide statistics and reporting bias make it difficult to make categorical statements. Those with a history of suicidal behaviour contribute substantially to the suicide rates. In this group subsequent suicidal behaviour is reported in 20% within one year (Kreitman 1977). Estimates of the subsequent suicide rate in this group range from 1 to 2% per annum which is between a hundred and two hundred times the expected rate for the general population. Whether they die or not these patients with suicidal behaviour are an at risk group associated with considerable suffering both for themselves and their friends and family. A strong association between suicide and depression has been assumed largely on the basis of retrospective analysis, which is subject to the bias inherent in even the most carefully conducted investigations. Prospective surveys of the prevalence of psychiatric illness in patients admitted to hospital following an episode of deliberate self harm vary but there is agreement that it appears to account for no more than around 40% of such admissions. In the Edinburgh survey depressive illness was a common diagnosis but accounted for only 28% of the men and 40% of the women. By far the largest category were patients with personality disorders. It is likely that any investigation of suicidal behaviour will need to look at the phenomenon in personality disorders separately from depressed patients.