CRD summary

The authors concluded cognitive-behavioural therapy was significantly more effective at reducing depressive symptoms (regardless of whether rated by clinicians or participants) than treatment as usual or being on a waiting list but not compared to active controls. The authors conclusions reflect the evidence presented and are likely to be reliable.

Authors' objectives

To evaluate the effectiveness of cognitive-behavioural therapy (CBT) for depression in older people and factors associated with its efficacy.

Searching

Cochrane Central Register of Controlled Trials (CENTRAL), PubMed and Web of Science were searched to December 2011. Search terms were reported. Reference lists of reviews were searched. Relevant journals were searched.

Study selection

Randomised controlled trials (RCTs) of cognitive-behavioural therapy for depression in older people (aged 50 or over) were eligible for inclusion. Control groups could be active or non-active such as treatment as usual or waiting-list conditions. Studies had to include more than five participants in each group. Participants had to be diagnosed with a major depression disorder, minor depression or dysthymia or report depressive symptoms on questionnaires. Relevant studies had to include sufficient data to enable calculation of effect sizes and report using evidence-based depression outcome measures. Studies of concomitant depression and neurodegenerative, neurological or severe psychiatric disorders were excluded.

CBT was compared with another form of psychotherapy, pharmacotherapy or CBT with another treatment. Most trials had a non-active control. Participant levels of depression varied between studies. The mean age of participants was 68.4 years (range 55 to 84). Half of the studies used a mixture of clinician and self-rated measures for depression; some studies used self-rated or clinician-rated measures only.

Two reviewers independently selected studies of inclusion. Disagreements were resolved through discussion.

Assessment of study quality

Quality was assessed using the Cochrane risk of bias tool for adequacy of sequence generation, allocation concealment, blinding of outcome assessors, incomplete outcome data and selective outcome reporting. Potential confounding factors were noted.

Two reviewers independently assessed quality. Disagreements were resolved through discussion.

Data extraction

Means and standard deviations (or standard errors) for each depression outcome measure in each condition at each time point were extracted to calculate between-group effect sizes. Response rates of numbers meeting or not meeting diagnostic criteria for depression or showing or not showing clinically significant improvements in scores were extracted for each condition at each time point and used to calculate odds ratios.

Two reviewers independently extracted data. Disagreements were resolved through discussion.

Methods of synthesis

Pooled standard mean differences (SMD) and odds ratios (OR) together with 95% confidence intervals (CI) were calculated using DerSimonian and Laird random-effects meta-analysis. Heterogeneity was assessed using the Q test and Ι² statistic. Separate analyses were conducted for active and non-active controls, for self-rated and clinician-rated measures and for remission. Meta-regression analysis was carried out to explore the influence of a wide variety of variables on intervention effects. Publication bias was assessed using funnel plots and Begg and Mazumdar test.

Results of the review

Twenty-three RCTs (1,803 participants, range 23 to 361) were included in the review. Only one RCT had adequate ratings in all areas of quality assessment. Ten RCTs reported three or more inadequate or unclear ratings. Incomplete outcome data and selective reporting of outcome data were most adequately addressed; randomisation sequence generation and allocation concealment were the least adequately addressed.

CBT versus non-active and active controls: Post intervention there was a large significant difference for CBT compared to non-active controls (treatment as usual or being on a waiting list) for clinician-rated measures (SMD -1.35, 95% CI -1.64 to -1.06; 10 RCTs; Ι²=31.8%) and a smaller significant difference for self-rated measures (SMD -0.57, -0.80 to -0.34; 14 RCTs; Ι²=64.2%). There was a significant difference in favour of CBT for clinician and self related measures at six month follow-up (SMD -0.50, 95% CI -0.95 to -0.05; Ι²=67%).

However there were no significant differences post intervention for CBT compared to active controls for either clinician rated (four RCTs; Ι²=61%) or self-rated measures of depression (five RCTs; Ι²=2%) at any of the time points.

Compared to non-active controls, participants who received CBT were significantly more likely to show remission (OR 6.98, 95% CI 3.04 to 16.02; four RCTs; Ι²=0%) or have a clinically significant improvement (OR 2.87, 95% CI 1.25 to 6.59; five RCTs; Ι²=62%).

CBT versus other Treatment, CBT plus other treatment versus CBT alone: There were no significant differences between CBT compared to other treatments or CBT plus other treatments compared to CBT only for clinician-rated or self-rated measures. Results were similar at all follow-up points. Significant heterogeneity was reported for some outcomes. There were no significant differences between participants who received CBT and those who received other treatments for remission (four RCTs; Ι²=0%).

Results of meta-regression were reported. There was no evidence of publication bias.

Authors' conclusions

Cognitive-behavioural therapy for depression in older people was more effective than being on a waiting list or treatment as usual but efficacy was not demonstrated over active controls or other treatment.

CRD commentary

The review question was clear with defined inclusion criteria. Several relevant sources were searched. It appeared that unpublished studies were not sought. Formal assessment of publication bias found no evidence of bias. It was unclear whether language restrictions were applied. Study quality was appropriately assessed. The studies appeared to be poorly reported, particularly regarding randomisation and allocation concealment. Appropriate methods to reduce reviewer error and bias were reported throughout the review process.

Methods used to combine studies and assess statistical heterogeneity appeared appropriate. There was significant statistical heterogeneity for some outcomes. The authors noted some limitations to generalisability due to non-demographically representative samples in half the studies, that most study participants were self-referrers and many studies allowed concurrent pharmacotherapy in the treatment group. Statistical significance was influenced by not controlling for pre-intervention scores.

The authors’ conclusions reflect the evidence presented and are likely to be reliable.

Implications of the review for practice and research

Practice: The authors did not state any implications for practice.

Research: The authors stated a need for more high-quality RCTs comparing cognitive-behavioural therapy with active controls to enable firm conclusions to be made regarding efficacy for older people with depression. Future studies should include self-rated and clinician rated outcomes. Further research was needed into other treatment approaches (such as pharmacotherapy) that could be contrasted with or augment cognitive-behavioural therapy.

Funding

National Institute for Health Research Dementia Biomedical Research Unit; Maudsley National Health Service Foundation Trust; King’s College, London.

Bibliographic details

Gould RL, Coulson MC, Howard RJ. Cognitive behavioral therapy for depression in older people: a meta-analysis and meta-regression of randomized controlled trials. Journal of the American Geriatrics Society 2012; 60(10): 1817-1830. [PubMed: 23003115]

Original Paper URL

http://onlinelibrary.wiley.com/doi/10.1111/j.1532-5415.2012.04166.x/abstract

Other publications of related interest

Gould RL, Coulson MC, Howard RJ. Efficacy of cognitive behavioral therapy for anxiety disorders in older people. A meta-analysis and meta-regression of randomised controlled trials. J Am Geriatr Soc 2012; 60: 218-229

Indexing Status

Subject indexing assigned by NLM

MeSH

Aged; Cognitive Therapy; Depression /therapy; Humans; Randomized Controlled Trials as Topic; Regression Analysis

AccessionNumber

12012049588

Database entry date

09/04/2013

Record Status

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.