Long-term Outcome of Lithium Prophylaxis in Bipolar Patients

To the Editor.—  Harrow and colleagues¹ rightly pointed out that, in routine clinical practice, lithium carbonate treatment is an effective prophylaxis for fewer than the 70% to 80% of manic patients previously described.The validity of their statement is even more evident if bipolar patients are followed up for more than the 1.7 years after hospital discharge Harrow et al used in their investigation, and it even holds in patients whose initial response to lithium carbonate had been favorable.Extending the sample described in a previous report,² we studied 50 patients with a DSM-III diagnosis of bipolar affective disorder who had completed a 2-year prophylactic treatment program with lithium carbonate and had been classified as responders, having had no relapse despite a reasonably high risk of recurrence (ie, history of at least one affective episode during the 2-year period preceding the index episode and the start of lithium