Samenvatting

Abstract
Background: Lifestyle interventions for severe mental illness (SMI) are known to have small to modest efect on physical health outcomes. Little attention has been given to patient-reported outcomes (PROs).
Aim: To systematically review the use of PROs and their measures, and quantify the efects of lifestyle interventions in patients with SMI on these PROs.

Methods: Five electronic databases were searched (PubMed/Medline, Embase, PsycINFO, CINAHL, and Web of Sci ence) from inception until 12 November 2020 (PROSPERO: CRD42020212135). Randomised controlled trials (RCTs) evaluating the efcacy of lifestyle interventions focusing on healthy diet, physical activity, or both for patients with SMI were included. Outcomes of interest were PROs.

Results: A total of 11.267 unique records were identifed from the database search, 66 full-text articles were assessed, and 36 RCTs were included, of which 21 were suitable for meta-analyses. In total, 5.907 participants were included across studies. Lifestyle interventions had no signifcant efect on quality of life (g=0.13; 95% CI=−0.02 to 0.27), with high heterogeneity (I2 =68.7%). We found a small efect on depression severity (g=0.30, 95% CI=0.00 to 0.58, I2 =65.2%) and a moderate efect on anxiety severity (g=0.56, 95% CI=0.16 to 0.95, I2 =0%).

Discussion: This meta-analysis quantifes the efects of lifestyle interventions on PROs. Lifestyle interventions have no signifcant efect on quality of life, yet they could improve mental health outcomes such as depression and anxiety symptoms. Further use of patient-reported outcome measures in lifestyle research is recommended to fully capture the impact of lifestyle interventions.