A long-term retrospective follow-up study of patients treated with prophylactic lithium carbonate.

Patients suffering from unipolar and bipolar affective illness, who began treatment with prophylactic lithium carbonate during a 5-year period, were followed up and 59 out of 101 interviewed. Most had been taking lithium for at least 13 years: 49% had a complete remission, 41% a partial but significant response, and 10% no response. No specific individual or illness factor was found to correlate with favourable outcome, and no correlation between average serum lithium level and outcome. No side-effects could be associated specifically with the long-term use of lithium, but there was a surprisingly high incidence of clinical hypothyroidism.