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Meta-Analysis
. 2024 Apr 30;50(3):489-495.
doi: 10.1093/schbul/sbad168.

Cat Ownership and Schizophrenia-Related Disorders and Psychotic-Like Experiences: A Systematic Review and Meta-Analysis

John J McGrath  1   2   3 , Carmen C W Lim  2 , Sukanta Saha  2
Affiliations
Meta-Analysis

Cat Ownership and Schizophrenia-Related Disorders and Psychotic-Like Experiences: A Systematic Review and Meta-Analysis

John J McGrath et al. Schizophr Bull. .

Erratum in

Abstract

Background: It has been proposed that cat ownership may be a risk-modifying factor for schizophrenia-related disorders and psychotic-like experiences (PLE). This study aimed to systematically review and meta-analyze publications that reported the relationship between cat ownership and schizophrenia-related outcomes.

Methodology: We searched Medline, Embase, CINAHL, Web of Science, and gray literature for publications between January 1, 1980, and May 30, 2023, regardless of geographical location and language. Backward citation search methods were used to locate additional articles. We included studies that reported original data on cat ownership and schizophrenia-related outcomes. We meta-analyzed estimates based on broad definitions (cat ownership, cat bites, and cat contact) with estimates with or without covariate adjustments. We pooled comparable estimates using random-effects models and assessed the risk of bias, heterogeneity, and study quality.

Results: We identified 1915 studies, of which 106 were chosen for full-text review, ultimately resulting in the inclusion of 17 studies. We found an association between broadly defined cat ownership and increased odds of developing schizophrenia-related disorders. For the studies reporting unadjusted odds ratios (OR; n = 10), the pooled OR was 2.14 (95% CI: 1.29-3.55). Exclusion of one outlier study resulted in a pooled OR (n = 9) of 1.56 (95% CI: 1.27-1.92). For the studies reporting adjusted estimates (n = 5), the pooled OR was 2.44 (95% CI: 1.59-3.73). After excluding one study with suboptimal exposure/design features, the pooled adjusted OR (n = 4) was 2.40 (95% CI: 1.50-3.86). We were unable to aggregate the estimates for the PLE outcomes because of the broad range of measures.

Conclusions: Our findings provide support for the hypothesis that cat exposure is associated with an increased risk of broadly defined schizophrenia-related disorders; however, the findings related to PLE as an outcome are mixed. There is a need for more high-quality studies in this field.

Prospero registration: PROSPERO 2023 CRD42023426974. Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023426974.

Keywords: cat ownership; meta-analysis; psychotic experiences; schizophrenia; schizotypy; systematic review.

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Conflict of interest statement

The authors have declared that there are no conflicts of interest in relation to the subject of this study.

Figures

Fig. 1.
Fig. 1.
PRISMA flowchart: Cat ownership and psychosis. Note: *No exposure group = no “cat ownership.” **No outcome group = no schizophrenia-related disorders.
Fig. 2.
Fig. 2.
Forest plot of the random-effects meta-analysis between cat exposure and schizophrenia-related disorders, unadjusted analyses.
Fig. 3.
Fig. 3.
Forest plot of the random-effects meta-analysis between cat exposure and schizophrenia-related disorders, adjusted analyses.
See this image and copyright information in PMC

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