Owning a Cat Could Double Your Risk of Schizophrenia, Research Suggests

Summary

Having a cat as a pet could potentially double a person's risk of schizophrenia-related conditions, according to an analysis of 17 studies.Psychiatrist John McGrath and colleagues at the Queensland Centre for Mental Health Research in Australia looked at papers published over the last 44 years in 11 countries, including the US and the UK.Their 2023 study found "a significant positive association between broadly defined cat ownership and an increased risk of schizophrenia-related disorders.""There is a need for more high-quality studies in this field," the authors emphasize in their published paper.Related: Adorable Cat Helps Scientists Discover New Virus (For Second Time)This idea that cat ownership could be linked to schizophrenia risk was proposed in a 1995 study, with exposure to a parasite called Toxoplasma gondii suggested as a cause. But the research so far has put forth mixed conclusions.Studies have found that being around cats during childhood might make a person more likely to develop schizophrenia; however, not all research has found an association.Toxoplasmosis is only known to reproduce in cats (1), but can be spread to humans through intermediate hosts (2, 5, 7) as well. (CDC)Some papers also link cat exposure to higher scores on scales that measure traits related to schizophrenia – which affects a person's thoughts, feelings, and behaviors – and psychotic-like experiences, but again, other studies don't show this connection.To get a clearer picture, McGrath and his team say there's a need for a thorough review and analysis of all the research on these topics.T. gondii is a mostly harmless parasite that can be transmitted through undercooked meat or contaminated water.A bite from an infected cat, or the cat's feces, can also transmit T. gondii can also be transmitted through a bite from an infected cat or through the cat's feces.Estimates suggest that T. gondii infects about 40 million people in the US, typically without any symptoms. Meanwhile, resear...