Psychosocial and behavioural interventions for the negative symptoms of schizophrenia: a systematic review of efficacy meta-analyses.

BACKGROUND: Currently there is no first-line treatment recommended for the negative symptoms of schizophrenia. Psychosocial and behavioural interventions are widely used to reduce the burden of negative symptoms. Meta-analytic studies have summarised the evidence for specific approaches but not compared evidence quality and benefit. AIM: To review and evaluate the evidence from meta-analytic studies of psychosocial and behavioural interventions for the negative symptoms of schizophrenia. METHOD: A systematic literature search was undertaken to identify all meta-analyses evaluating psychosocial and behavioural interventions reporting on negative symptom outcomes in people with schizophrenia. Data on intervention, study characteristics, acceptability and outcome were extracted. Risk of bias was evaluated. Results were summarised descriptively, and evidence ranked on methodological quality. RESULTS: In total, 31 systematic reviews met the inclusion criteria evaluating the efficacy of negative symptom interventions on 33 141 participants. Exercise interventions showed effect sizes (reduction in negative symptoms) ranging from -0.59 to -0.24 and psychological interventions ranging from -0.65 to -0.04. Attrition ranged between 12% to 32%. Across the studies considered heterogeneity varied substantially (range 0-100). Most of the reviews were of very low to low methodological quality. Methodological quality ranking suggested that the effect size for cognitive remediation and exercise therapy may be more robust compared with other approaches. CONCLUSIONS: Most of the interventions considered had a small-to-moderate effect size, good acceptability levels but very few had negative symptoms as the primary intervention target. To improve the confidence of these effect sizes being replicated in clinical settings future studies should minimise risk of bias.

Virtual Reality Therapy for the Negative Symptoms of Schizophrenia (V-NeST): A pilot randomised feasibility trial.

BACKGROUND: Negative symptoms are typically observed in people with schizophrenia and indicate a loss or reduction of normal function (e.g. reduced motivation and affect display). Despite obstructing people's recovery, intervention development has received limited attention. This study tests the feasibility and acceptability of a novel Virtual Reality Supported Therapy for the Negative Symptoms of Schizophrenia (V-NeST). METHOD: A single (rater) blind randomised study with two conditions; V-NeST plus treatment as-usual (TAU) vs. TAU alone, recruiting people with schizophrenia experiencing debilitating negative symptoms. Assessment was at baseline and 3-month post-randomisation. The pre-specified primary outcome was participants' goal attainment, secondary outcomes were negative symptoms and functioning. The study assessed feasibility and acceptability parameters including recruitment, eligibility, treatment adherence and retention. Acceptability was also evaluated qualitatively using a post-therapy feedback interview. Explorative therapy effect on outcomes was estimated. RESULTS: The study recruited to its pre-specified target of 30 participants (15 randomised to V-Nest). Two participants in each trial arm disengaged and did not complete the study. Therapy engagement for those randomised to V-NeST was appropriate and research procedures were feasible. The experience with therapy and VR was described as positive and useful. Preliminary analysis suggested the therapy may have a large effect on participants goals and a possible effect on negative symptoms. CONCLUSION: V-NeST is a feasible and acceptable intervention. This therapy has the potential to support people with schizophrenia achieving their recovery goals and may reduce negative symptoms. The efficacy results need to be evaluated in an appropriately powered efficacy study.