The effect of prophylactic lithium treatment on mortality and suicidal behavior: a review for clinicians

Prophylactic lithium treatment lowers the frequency of recurrences in manic depressive illness. Does it also reduce mortality and suicidal behavior? In this paper all relevant publications were reviewed. The mortality of lithium-treated patients was compared with the mortality in the general population, and the patients' suicidal behavior when they were on lithium was compared with their behavior when they were not. The mortality of manic depressive patients is two to three times higher than that of the general population, a highly significant difference. In the studies reviewed here the patients' mortality during lithium treatment was not significantly higher or only moderately higher than in the general population. After discontinuation of lithium the mortality was again significantly higher. The number of patients attempting suicide was 6-15 times lower and the number of patients completing suicide was 3-17 times lower when they were on lithium than they were not. Similar observations have not been reported for prophylactic treatment with other mood stabilizers. For methodological reasons explained in the introduction, these observations cannot prove that lithium treatment has a mortality-lowering, antisuicidal effect. But they are compatible with such an assumption. It must be the duty of psychiatrists to keep the possibility of an antisuicidal action of lithium in mind when they choose prophylactic treatment for patients with severe depressions or suicidal thoughts or suicide attempts in the past or combinations of these.