This review compared the efficacy, withdrawal rates and side effects of different antidepressant classes in the treatment of depression in older people. Thirty-two studies provided data for the review. Our main findings indicate that tricyclic antidepressants (classical and tricyclic related) and selective serotonin reuptake inhibitors (SSRIs) are equally efficacious. However, when comparing the two tricyclic groups with SSRIs we found that tricyclic related antidepressants were similar to SSRIs in terms of overall withdrawal rate, and classical tricyclic antidepressants were associated with a higher withdrawal rate due to side effects. These findings are reflected in the differing side effect profiles when comparing both tricyclic groups with SSRIs. The findings of the review must be interpreted with some caution in view of the relatively low patient numbers and lack of side effect data.
Our findings suggest that SSRIs and TCAs are of the same efficacy. However, we have found some evidence suggesting that TCA related antidepressants and classical TCAs have different side effect profiles and are associated with differing withdrawal rates when compared with SSRIs. The review suggests that classical TCAs are associated with a higher withdrawal rate due to side effect experience, although these results must be interpreted with caution due to the heterogeneity of the drugs and patient populations.
Depression is a relatively common experience in older adults. The syndrome is associated with considerable distress, morbidity and service commitment. Approximately two thirds of patients presenting with severe forms will respond to antidepressant treatment and the last twenty years has witnessed a great increase in the number of these drugs. Older, frail people are particularly vulnerable to side effects.
The aims of this review were to examine the efficacy of antidepressant classes, to compare the withdrawal rates associated with each class and describe the side effect profile of antidepressant drugs for treating depression in patients described as elderly, geriatric, senile or older adults, aged 55 or over.
The Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register (CCDANCTR-Studies) was searched (2003-08-13). Reference lists of relevant papers and previous systematic reviews were hand searched for published reports and citations of unpublished studies.
Only randomised controlled trials were included. Trials had to compare at least two active antidepressant drugs in the treatment of depression.
Reviewers extracted data independently. In examining efficacy, the reviewers assumed that people who died or dropped out had no improvement. Withdrawal rates irrespective of cause and specifically due to side effects were compared between drug classes. Relative risk (RR) for dichotomous data and weighted mean difference for continuous data were calculated with 95% confidence intervals (CI). Qualitative side effect data were reported in terms of ratios of side effects and percentage of patients experiencing specific side effects.
A total of 32 trials provided data for inclusion in the review in terms of efficacy, withdrawal and side effect analysis. We were unable to find any differences in efficacy when comparing classes of antidepressants. Tricyclic antidepressants (TCAs) compared less favourably with selective serotonin reuptake inhibitors (SSRIs) in terms of numbers of patients withdrawn irrespective of reason (RR: 1.23, CI 1.05 to 1.43) and number withdrawn due to side effects (RR: 1.36, CI 1.09 to 1.70). Further analyses demonstrated that TCA related antidepressants had similar withdrawal rates to SSRIs irrespective of reason of withdrawal (RR: 1.49, CI 0.74 to 2.98) or withdrawal due to side effects (RR: 1.07, CI 0.43 to 2.70). The qualitative analysis of side effects showed a small increased profile of gastro-intestinal and neuropsychiatric side effects associated with classical TCAs.