Continuation and maintenance treatments for depression in older people

Philip Wilkinson, Zehanah Izmeth

Depressive illness is common in old age. Prevalence in the community of case level depression is around 15% and milder forms of depression are more common. It causes significant distress and disability. The number of people over the age of 60 years is expected to double by 2050 and so interventions for this often long-term and recurrent condition are increasingly important. The causes of late-life depression differ from depression in younger adults and so it is appropriate to study it separately.This is an update of a Cochrane review first published in 2012. To examine the efficacy of antidepressants and psychological therapies in preventing the relapse and recurrence of depression in older people. We performed a search of the Cochrane Common Mental Disorders Group's specialised register (the CCMDCTR) to 13 July 2015. The CCMDCTR includes relevant randomised controlled trials (RCTs) from the following bibliographic databases: The Cochrane Library (all years), MEDLINE (1950 to date), EMBASE (1974 to date), and PsycINFO (1967 to date). We also conducted a cited reference search on 13 July 2015 of the Web of Science for citations of primary reports of included studies. Both review authors independently selected studies. We included RCTs involving people aged 60 years and over successfully treated for an episode of depression and randomised to receive continuation and maintenance treatment with antidepressants, psychological therapies, or a combination. Two review authors independently extracted data. The primary outcome for benefit was recurrence rate of depression (reaching a cut-off on any depression rating scale) at 12 months and the primary outcome for harm was drop-outs at 12 months. Secondary outcomes included relapse/recurrence rates at other time points, global impression of change, social functioning, and deaths. We performed meta-analysis using risk ratio (RR) for dichotomous outcomes and mean difference (MD) for continuous outcomes, with 95% confidence intervals (CI). This update identified no further trials. Seven studies from the previous review met the inclusion criteria (803 participants). Six compared antidepressant medication with placebo; two involved psychological therapies. There was marked heterogeneity between the studies.Comparing antidepressants with placebo on the primary outcome for benefit, there was a statistically significant difference favouring antidepressants in reducing recurrence compared with placebo at 12 months with a GRADE rating of low for quality of evidence (three RCTs, n = 247, RR 0.67, 95% CI 0.54 to 0.82; number needed to treat for an additional beneficial outcome (NNTB) 5). Comparing antidepressants with placebo on the primary outcome for harms, there was no difference in drop-out rates at 12 months' follow-up, with a GRADE rating of low.There was no significant difference between psychological treatment and antidepressant in recurrence rates at 12 months (one RCT, n = 53) or between combination treatment and antidepressant alone at 12 months. This updated Cochrane review supports the findings of the original 2012 review. The long-term benefits and harm of continuing antidepressant medication in the prevention of recurrence of depression in older people are not clear and no firm treatment recommendations can be made on the basis of this review. Continuing antidepressant medication for 12 months appears to be helpful with no increased harms; however, this was based on only three small studies, relatively few participants, use of a range of antidepressant classes, and clinically heterogeneous populations. Comparisons at other time points did not reach statistical significance.Data on psychological therapies and combined treatments were too limited to draw any conclusions on benefits and harms.The quality of the evidence used in reaching these conclusions was low and the review does not, therefore, offer clear guidance to clinicians and patients on best practice and matching interventions to particular patient characteristics.Of note, we identified no new studies that evaluated pharmacological or psychological interventions in the continuation and maintenance treatment of depression in older people. We are aware of studies conducted since the previous review that included both older people and adults under the age of 65 years, but these fall outside of the remit of this review. We believe that there remains a need for studies solely recruiting older people, particularly the 'older old' with comorbid medical problems. However, these studies are likely to be challenging to conduct and may not, so far, have been prioritised by funders.