Influence of age on the efficacy of electroconvulsive therapy in major depression: A retrospective study
Background: Several variables have been studied as possible predictors for the efficacy of ECT, results from the few studies assessing the influence of age on the efficacy of ECT were inconsistent. In older patients suffering from severe depression, ECT is often the treatment of choice, therefore, investigating the influence of age on ECT response is considered relevant. Method: At two depression units, 141 patients meeting DSM-IV criteria for major depression and scores of at least 18 on the 17-item Hamilton Rating Scale for Depression (HAM-D) were treated with bilateral ECT, twice weekly. Clinical evaluation of depressive symptoms was performed each week; scores on the HAM-D were obtained 1-3 days prior to ECT and 1-3 days after termination of the ECT course. The primary outcome criterion was defined a priori as the mean change on the HAM-D score. The influence of age on mean change on the HAM-D score was analyzed with multiple linear regression analysis, adjusted for three covariables: center, duration of the index episode and presence of psychotic features. Results: Age as a continuous variable had no significant effect on the efficacy of ECT as measured by mean change on the HAM-D score (SE 0.057, p = 0.84). Limitations: The disproportionate distribution of patients among the three age groups appears to be the major limitation of the present study. Conclusion: This study suggests that the efficacy of ECT in elderly depressed patients is at least equal to that in younger depressed patients.