More on physical exercise worsening dementia

This week's issue of ALZ Forum included an article about the study published in The BMJ that found physical exercise seemed to "slightly" worsen dementia.  The article pointed out that this was a big surprise, but there were some facts in the article I hadn't seen before.  Most important was that the study subjects were not living in institutions, but they had nevertheless advanced to the stage of their disease where they required the service of a caregiver.  Recall that dementia is defined based on an individual's inability to perform their daily activities.

A few statistics:  There were 494 test subjects with an average age of 77.  The population was about 60% male, 40% female.  329 followed an exercise program, while 165 did not.  Exercise consisted of a mix of 30 minutes of aerobic exercise + some weight training.  There were two supervised sessions per week.  

The article quoted Laura Baker of Wake Forest School of Medicine, who contrasted these results with her success with treating mild cognitive impairment with exercise.  She also wondered about the design of the research.  She said, "In my work with patients with mild cognitive impairment, it takes at least six months of moderate to high-intensity aerobic exercise, with weekly trainer support and accountability, to see improvements in executive function.  To get similar improvements in people with dementia, they might need to exercise for a longer period of time.”

My conclusion:  Physical exercise clearly improves cognition in people with MCI, at least if it's due to AD.  Physical exercise may not improve cognition in people with actual dementia, but it still improves their overall health.  Most importantly, it helps prevent falls in older adults.