Does Owning a Cat Double the Risk of Schizophrenia?

A recent review conducted by psychiatrist John McGrath and fellow researchers from the Queensland Centre for Mental Health Research suggests that owning a cat as a pet could potentially double a person’s risk of schizophrenia-related disorders. This finding has sparked interest and concern, as it challenges previous studies on the topic that have presented mixed conclusions. In this article, we will delve into the details of the review, analyze its methodology and findings, and explore the possible implications of cat ownership on schizophrenia risk.

The Association between Cat Ownership and Schizophrenia

The idea that cat ownership could be linked to an increased risk of schizophrenia was initially proposed in a 1995 study. This study suggested that exposure to a parasite called Toxoplasma gondii, which can be transmitted through contact with cat feces or by consuming undercooked meat, could be a potential cause for the association. However, subsequent research has yielded inconsistent results, with some studies finding a connection between cat exposure and schizophrenia-related traits, while others have not.

Need for a Thorough Review

Recognizing the conflicting findings in existing studies, McGrath and his team conducted a thorough review and analysis of the research on cat ownership and schizophrenia risk. Their analysis included 17 studies and aimed to provide a clearer picture of the association. The review found a significant positive association between broadly defined cat ownership and an increased risk of schizophrenia-related disorders.

It is important to note the limitations of the studies included in the review. The majority of the studies were case-control studies, which cannot establish causation and often do not consider other factors that might influence the results. Additionally, some of the studies were of low quality, potentially affecting the reliability of the findings.

Inconsistencies in the Findings

The review revealed inconsistencies in the findings, further complicating the understanding of the association between cat ownership and schizophrenia. One study found no significant association between owning a cat before the age of 13 and later developing schizophrenia. However, when narrowing down cat ownership to a specific period (ages 9 to 12), a significant link was observed. This suggests that the crucial time frame for cat exposure is not clearly defined.

Possible Role of Parasites

While T. gondii has been associated with personality changes, the emergence of psychotic symptoms, and neurological disorders including schizophrenia, the link between the parasite and these changes is not definitive. Moreover, it cannot be confirmed that the parasite was passed on to humans from cats. Other pathogens, such as Pasteurella multocida, may also be responsible for the observed effects.

The review emphasizes the need for better and broader research before any firm interpretations or conclusions can be drawn. While the association between cat ownership and schizophrenia-related disorders has been identified, the underlying mechanisms and potential confounding factors need to be thoroughly investigated. Additionally, the role of other pathogens and their impact on schizophrenia risk should be explored.

The review conducted by McGrath and his team provides support for an association between cat ownership and schizophrenia-related disorders. However, it is important to approach these findings with caution due to the limitations of the included studies and the inconsistencies in the results. Further research is needed to gain a comprehensive understanding of the relationship between cat ownership, parasite exposure, and schizophrenia risk. Until then, cat owners and individuals at risk of schizophrenia should not be unduly alarmed by these findings, but rather remain informed about the ongoing research in this area.