Psychopathology during long-term lithium treatment of patients with major affective disorders. A prospective study.

Thirty-seven patients with major affective disorders according to DSM-III and on continuous lithium treatment were followed during a 7-year period. Outcome was assessed by use of the Comprehensive Psychopathological Rating Scale and by the need for additional psychotropic medication and for hospital and outpatient care. Anamnestic variables and patient's attitudes to their lithium medication were also included in the analysis of outcome, as were laboratory data, including lithium parameters. An increase in psychopathology was demonstrated in a significant number of patients and was attributed mainly to an increase in the depressive symptoms, with a significant increase in the rated scores for fatiguability, pessimistic thoughts, reduced sleep, and inner tension. Suicidal thoughts were common, but no suicide attempts were made. A significant number of patients complained of failing memory, but no significant progression was demonstrated during the 7-year study period. The increase in the depressive symptoms was closely correlated with the number of hospital admissions for depressive recurrence and with the number of days in hospital. The following factors showed a significant relationship with the increase in depressive symptoms: serum lithium levels, large increase in the elimination half-life of lithium, low level of social functioning, low TSH values, and need of concomitant administration of antidepressants and benzodiazepines.