|Meta-analysis of cognitive-behavioral interventions on HIV-positive persons' mental health and immune functioning
|Crepaz N, Passin WF, Herbst JH, Rama SM, Malow RM, Purcell DW, Wolitski RJ
This generally well-conducted review found that cognitive behavioural interventions improved various psychological states in patients with human immunodeficiency virus, but there was limited evidence to determine effects on immune functioning. The authors' conclusions were supported by the results, but should be interpreted with some caution due to the small number and size of included studies and limited quality assessment.
To evaluate the efficacy of cognitive-behavioural interventions for improving the mental health and immune functioning of people with human immunodeficiency virus (HIV).
AIDSLINE, MEDLINE, EMBASE, PsycINFO, and Sociological Abstracts were searched from 1988 to 2005. Some details of the search strategy were reported. Trial registries were searched, 35 Key journals were handsearched from June 2002 to December 2005, researchers were contacted to identify unpublished studies and reference lists of retrieved studies were screened. No language or publication restrictions were applied.
Randomised and non-randomised controlled trials that assessed the effects of cognitive behaviour interventions to assist people with HIV and that reported sufficient data to calculate effect sizes for at least one negative psychological state (symptoms of depression, anger, anxiety stress) or biologic outcome related to immune functioning (CD4 or CD8) were eligible for inclusion. Trials were excluded if they explicitly allowed participants to self-select into interventions, if they evaluated the intervention in only one group or assessed intervention efficacy on the basis of behaviour change from before to after the intervention. Authors were contacted for additional information where necessary.
Most studies were conducted in USA; single trials were conducted in Hong Kong, China, Canada and the Netherlands. Age ranged from 34 to 47 years (median 37). Seven studies were conducted in men only and one in women only; the rest contained mixed samples (64% to 91% men). Median time since diagnosis of HIV was 4.7 years (range one to seven years). Studies targeted symptomatic or AIDS patients, asymptomatic patients with HIV and newly diagnosed patients with HIV. Some studies particularly targeted patients with depression at baseline. Interventions included appraisal/cognitive restructuring techniques, coping skills training, stress management skills training and social support. Most studies involved group-based interventions; some targeted individuals. Interventions were delivered by professional psychologists or psychiatrists or by trained research staff. Comparator groups were waiting list controls, standard care or other interventions. The number of intervention sessions ranged from three to 17. Some patents also received medication. All studies used standard psychological scales to assess outcomes.
The authors did not state how many reviewers selected studies for inclusion.
Assessment of study quality
Two reviewers independently assessed study quality based on the criteria of assignment method, type of control group, participation rate, sample size, overall and differential retention and intention-to-treat analysis. Disagreements were resolved through consensus.
Two reviewers independently extracted data to calculate standardised mean differences (Cohen's d) calculated as the difference between intervention and control group scores divided by the pooled standard deviation of the two groups. The Hedges correction was applied to obtain an unbiased estimate. If studies reported data separately for different samples (for example, men and women) data were extracted for each sample. If studies reported data for multiple time points, data were extracted for the first post-intervention assessment. Data were extracted from adjusted models where possible. Disagreements were resolved through consensus.
Methods of synthesis
Summary effect sizes and their 95% confidence intervals (CIs) were estimated using inverse variance weighted pooling. Both fixed-effect and random-effects models were used; results for random effects models were reported. Data were pooled separately for depression, anger, anxiety, stress and biological markers of immune function (CD4 count). Heterogeneity was assessed using the Q statistic. Sensitivity analysis was conducted to determine the effects of methodological quality and intervention characteristics and to assess the influence of each individual trial on summary estimates. Publication bias was assessed using funnel plots and the Egger test.
Results of the review
Fifteen studies were included (n=1,246, range 16 to 154): 13 RCTs and two non-randomised studies. Withdrawal rates ranged from 2% to 46%. All trials analysed data on an intention-to-treat basis.
The intervention resulted in significant improvements in depression (d 0.33, 95% CI 0.13 to 0.54; 13 trials), anxiety (d 0.30, 95% CI 0.06 to 0.54; 10 trials), anger (d 1.00, 95% CI 0.23 to 1.77; five trials) and stress (d 0.43, 95% CI 0.20 to 0.67; four trials) immediately post intervention. The effects on CD4 count were not significant. There was evidence of heterogeneity for all outcomes except CD4 count. Sensitivity analysis showed that no single trial exerted an influence on the summary effect sizes. Effects were no longer significant at follow-up at a mean of six months post intervention.
There was no evidence of publication bias. Results of sensitivity analyses were reported in the review.
Cognitive-behavioural interventions were effective in improving various psychological states in patients with HIV. There was limited evidence for effects on immune functioning.
The review addressed a focused question supported by clearly defined inclusion criteria. An extensive literature search was conducted, which included attempts to minimise language and publication bias. Appropriate steps were taken to minimise bias and errors in data extraction and quality assessment; it is unclear whether such steps were taken during study selection. Relevant details of individual studies were clearly summarised, which helped readers to determine the generalisability of the findings. Study quality was formally assessed using some relevant criteria, but randomisation method, allocation concealment and blinding were not assessed. Methods used to pool data were appropriate and clearly presented. Heterogeneity was formally assessed and investigated.
The authors' conclusions were supported by the results, but should be interpreted with some caution due to the small number and size of included studies, short duration of follow-up and limitations in the quality assessment.
Implications of the review for practice and research
Practice: The authors stated that cognitive-behavioural interventions can improve mental health of patients with HIV. Clinicians and policy makers must recognise that mental health services must be available to effectively treat patients with HIV and that patients may need ongoing or periodic provision of cognitive behavioural interventions.
Research: The authors stated that prospective controlled studies to evaluate the impact of cognitive behavioural interventions on larger and more generalisable cohorts were required. Future trials should assess outcomes at multiple-assessment period for longer periods after the intervention. Future research should examine the relationships among interventions, psychological states, medication adherence and immune functions.
Prevention Research Branch, Division of HIV/AIDS prevention, US Centers for Disease Control and Prevention.
Crepaz N, Passin WF, Herbst JH, Rama SM, Malow RM, Purcell DW, Wolitski RJ. Meta-analysis of cognitive-behavioral interventions on HIV-positive persons' mental health and immune functioning. Health Psychology 2008; 27(1): 4-14
Subject indexing assigned by NLM
Adult; Anger; Anxiety; Cognitive Therapy; Depression; Female; HIV Seropositivity /immunology /psychology; Humans; Immune System /metabolism; Male; Mental Health; Middle Aged; Stress, Psychological; Treatment Outcome; United States
Date bibliographic record published
Date abstract record published
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.