In a comprehensive study led by the Tokyo Metropolitan Institute of Gerontology and Gerontology, published in the December 2023 issue of the U.S. National Library of Medicine, researchers found a noteworthy link between pet ownership and the risk of dementia in older adults.
The study, which involved more than 11,000 people aged 65 to 84, representing about 10% of the elderly population in Ota, Tokyo, Japan, explored the link between pet ownership, particularly cats and dogs, and weekly exercise habits, including activities such as walking, running, yoga, swimming and cycling. The four-year study used data from the Long-Term Care Insurance System (LTCI) to analyze incidents of disabling dementia among participants.
The study found that dog ownership played a role in reducing the development of severe dementia over a follow-up period of about four years, after taking into account various contextual factors. It is worth noting that dog owners who exercise regularly and are not socially isolated have a significantly lower risk of developing severe dementia. Even under restrictions like those during the COVID-19 pandemic, the act of caring for a dog may help maintain physical activity, including daily exercise, and promote social engagement.
In summary, the study found:
Owning a dog reduces the likelihood of developing severe and disabling dementia.
Dog owners who exercise and socialize regularly can significantly reduce their risk of developing dementia.
On the other hand, the effect of cat ownership on preventing dementia was less pronounced compared to owning a dog (the study found that dog owners had a calculated odds risk of 0.6, compared with 0.98 for cat owners).
The findings, which show that dog owners have a lower risk of developing dementia than cat owners or non-pet owners, are of particular interest in the field of dementia research. The study used the "odds ratio" method for analysis, and the results showed that the risk coefficient for dog owners was 0.6, while the risk coefficient for cat owners was slightly higher at 0.98, and the baseline risk for people without any pets was 1.0.
An important finding of this study is that pet dogs have a significant impact on their owners' lifestyles. Dog owners generally get outside more often, which increases social interaction. This increase in social activity is thought to have an "inhibitory effect" on the development of dementia. Additionally, the physical activity associated with dog ownership, such as regular walks, is thought to reduce the buildup of brain proteins associated with dementia. Regular exercise also increases blood flow to the brain, cell growth and survival, factors that reduce the risk of cognitive decline.
The study's lead author, Dr. Yu Taniguchi, noted that owning a dog is beneficial in reducing the risk of disabling dementia.
The study found that current dog owners were 40% less likely to develop disabling dementia (odds ratio 0.60, 95% confidence interval 0.37-0.977) compared with previous dog owners or those who had never owned a dog. In comparison, the odds ratio for cat owners was 0.98 (95% confidence interval, 0.62-1.55), indicating a minimal difference in risk of dementia. Compared with people who had or had never owned a dog but did not exercise, people who currently owned a dog and exercised regularly were 63% less likely to develop disabling dementia, with an odds ratio of 0.37 (95% confidence interval, 0.20-0.68).
"Over a follow-up period of about four years, dog ownership had a suppressive effect on the development of disabling dementia, after adjusting for background factors. Dog owners who had exercise habits and no social isolation had a significantly lower risk of developing disabling dementia," said Dr. Taniguchi.
Additionally, the study concluded that owning a dog can encourage continued physical activity and develop consistent exercise habits. Research suggests this is particularly beneficial in promoting social participation and healthy lifestyles.
Summarize
Dog owners who exercise regularly and are not socially isolated have the lowest risk of developing severe dementia. However, the team cautions that simply owning a dog may not be enough to protect against dementia if the owner leads a sedentary lifestyle with limited social interaction. The research team emphasizes that if dog owners do not engage in daily activities related to caring for their dogs, such as exercise and socialization, then the positive effects in preventing dementia cannot be observed.
The study also highlighted cultural issues, noting that Japan has lower rates of cat and dog ownership than in Western countries such as the United States. This raises an interesting question for future research - to explore whether the patterns found in Japan also apply to Western countries and other countries.
The World Health Organization (WHO) emphasizes that dementia is a major health problem globally. Currently, there are approximately 50 million people with dementia worldwide, and nearly 10 million new cases are diagnosed every year. This global prevalence highlights the importance of understanding all potential factors that help prevent dementia, including lifestyle choices such as pet ownership and physical activity.