Owning a Cat Can Make a Person More Susceptible to Schizophrenia, Study Reveals

Cats are amazing creatures that make great pets. About 370 million cats are kept as cats every year. A new study, however, reveals that being a cat owner can double a person's risk of developing schizophrenia.

Danger of Cat Ownership

At the Queensland Centre for Mental Health Research in Australia, experts analyzed 17 studies from 11, including the U.S. and the U.K., over the past 44 years. They found a connection between broadly defined cat ownership and increased odds of developing schizophrenia-related disorders.

Led by Dr. John McGrath, a team of researchers discovered that people who were exposed to cats before the age of 25 were around twice as likely to develop schizophrenia. The study's findings are presented in the paper "Cat Ownership and Schizophrenia-Related Disorders and Psychotic-Like Experiences: A Systematic Review and Meta-Analysis."

In 1995, research suggested that some cases of schizophrenia may be due to viruses that come from house cats. It is acquired through the parasite Toxoplasma gondii, which enters the body through cat bites.

As the parasite enters the central nervous system, it affects neurotransmitters in the brain and leads to personality changes, psychotic symptoms, and psychiatric disorders like schizophrenia. However, the authors claimed that further research was needed to confirm the potential link. Since then, not all studies have found the mysterious association.

The team behind the latest meta-analysis, an overview of different studies, discovered a significant positive correlation between broadly defined cat ownership and an increased risk of schizophrenia-related disorders. They claim that after adjusting for covariates, they realized that individuals who are exposed to cats had approximately twice the risk of developing chronic mental illness.

However, it is essential to note that the findings across the studies were inconsistent, and 15 out of 17 case studies were case-control. This means they cannot determine a cause and effect as it does not look at external factors.

For instance, a study in the U.S. involved 354 students and did not find an association between cat ownership and scores on the schizotypy scale, a questionnaire that helps diagnose schizophrenia. Instead, it found that when those bitten by a cat were compared to those not bitten, the bitten subgroup had higher scores on the scale.

The authors suggest that further research be done before making any firm interpretations. More high-quality studies must be conducted based on large, representative samples to better understand cat ownership as a candidate risk-modifying factor for mental disorders.

What Is Schizophrenia?

Schizophrenia is a severe mental disorder where a person interprets reality abnormally. This condition is described as a type of psychosis and does not usually cause a person to be violent.

Schizophrenia involves a range of problems with behavior, thinking, and emotions. Its symptoms typically begin between the mid-to-late 20s but can also start later. Although signs and symptoms may vary, they usually involve hallucinations, delusion, disorganized speech, and an impaired ability to function.

The cause of schizophrenia is not well understood. Experts believe that this mental illness results from combined factors like abnormalities in brain chemistry, genetics, and possible viral infections and immune disorders.