BACKGROUND: The efficacy of lithium augmentation in therapy-resistant depression has been shown in a series of well-designed, placebo-controlled studies. However, little is known about the predictors of a good response to this treatment strategy. METHODS: We retrospectively examined the predictive value of 20 demographic, clinical, biochemical and endocrinological variables using a two-step logistic regression. Seventy-one in-patients with depression refractory to tricyclic antidepressants had received lithium augmentation as part of a standardised treatment protocol. RESULTS: Within 4 weeks 37 patients (52%) responded to lithium augmentation. Five variables with predictive value were found. Responders were more severely depressed according to the Bech-Rafaelsen Melancholia Scale. The duration of their index episode was shorter. Triiodothyronine serum levels were lower and neuroleptic co-medication and co-diagnosis of personality disorder were less frequent. LIMITATIONS: This was an open, retrospective study. CONCLUSIONS: Severity of depression is a predictor of response to lithium augmentation. This result conflicts with recent studies but is similar to results found in studies of other pharmacological antidepressant strategies.
BACKGROUND: The efficacy of lithium augmentation in therapy-resistant depression has been shown in a series of well-designed, placebo-controlled studies. However, little is known about the predictors of a good response to this treatment strategy. METHODS: We retrospectively examined the predictive value of 20 demographic, clinical, biochemical and endocrinological variables using a two-step logistic regression. Seventy-one in-patients with depression refractory to tricyclic antidepressants had received lithium augmentation as part of a standardised treatment protocol. RESULTS: Within 4 weeks 37 patients (52%) responded to lithium augmentation. Five variables with predictive value were found. Responders were more severely depressed according to the Bech-Rafaelsen Melancholia Scale. The duration of their index episode was shorter. Triiodothyronine serum levels were lower and neuroleptic co-medication and co-diagnosis of personality disorder were less frequent. LIMITATIONS: This was an open, retrospective study. CONCLUSIONS: Severity of depression is a predictor of response to lithium augmentation. This result conflicts with recent studies but is similar to results found in studies of other pharmacological antidepressant strategies.