Couch potatoes beware, excessive time spent on the sofa may increase dementia risk

Recent research from the University of Arizona and the University of Southern California (USC) has uncovered a concerning link between sedentary lifestyles and dementia risk among individuals aged 60 and above.

The study found that those who spend more than 10 hours daily in sedentary activities, such as prolonged TV viewing or extended periods of driving, face a significantly heightened risk of developing dementia.

Furthermore, the findings, which were published in the Journal of the American Medical Association, highlighted the manner in which sedentary activities are distributed throughout the day holds less importance than the overall daily duration of such inactivity.

“We were surprised to find that the risk of dementia begins to rapidly increase after 10 hours spent sedentary each day, regardless of how the sedentary time was accumulated,” said study co-author Gene Alexander, a UArizona professor of psychology and psychiatry and a professor in the university’s Evelyn F. McKnight Brain Institute and BIO5 Institute.

“This suggests that it is the total time spent sedentary that drove the relationship between sedentary behavior and dementia risk. But, importantly, lower levels of sedentary behavior, up to around 10 hours, were not associated with increased risk.”

The researchers tapped into the U.K. Biobank, a large UK health database, to explore whether excessive sitting relates to dementia risk.

In a U.K. Biobank sub-study, over 100,000 adults wore wrist-worn devices for a week to track their activity. They focused on around 50,000 adults aged 60 and up who didn’t have dementia at the study’s outset.

They then sifted through the data from these devices, distinguishing various activities like sitting or sleeping. This helped them determine how much time people spent sitting.

After roughly six years, they checked hospital records and identified 414 cases of dementia.

To ensure their findings were solid, they considered factors like age, gender, education, health conditions, genetics, and lifestyle choices such as exercise, diet, smoking, drinking, and mental health.

This study builds on their earlier research that examined how different types of sedentary behavior, like sitting and watching TV, influence the risk of dementia.

“Our latest study is part of our larger effort to understand how sedentary behavior affects brain health from multiple perspectives,” lead study author David Raichlen, professor of biological sciences and anthropology at USC said.

“In this case, wearable accelerometers provide an objective view of how much time people dedicate to sedentary behavior that complements our past analyses.”

The study authors stressed the need for more research in order to determine if physical activity can actually lower the risk of getting dementia.