Tuesday’s blog was about a single study that seemed to show that if you had dementia, exercise didn’t help. Today I’ll review a meta-analysis that concludes the opposite. So let’s dive in!
What the Heck Is a Meta-Analysis?
You have seen in the news that one day a study concludes x, and then the next month, you hear about another study on the same topic that concludes y. Scientists also recognize this problem; hence, they invented the meta-analysis. This technique takes apart many studies and then reassembles all of the patients into one or more big groups. The idea is that there is power in numbers, and as a result, comparing a bigger number of patients to a bigger number of patients is likely more valid than comparing smaller groups.
Dementia and Cognitive Impairment
Alzheimer’s dementia, dementia with Lewy bodies (DLB), vascular dementia…whatever specific type it comes in, dementia is a slowly progressing degenerative brain disease in which the brain cells die or deteriorate due to damage. You might first notice mild cognitive impairments either in yourself or a loved one.
Cognitive impairment includes trouble processing thoughts or remembering things. Though “cognitive impairment” doesn’t automatically mean a diagnosis of dementia (it could also be a result of a stroke or brain injury for example), even mild cognitive impairment is associated with a greater chance of developing dementia. In addition, Alzheimer’s disease and other dementias do cause cognitive impairment, so in many cases, it’s a warning sign of the early stage of a dementia disease.
While cognitive impairments due to an acute condition or a medication, for example, may only be temporary, those due to degenerative diseases, such as dementia, will slowly worsen. However, while it won’t reverse dementia, exercise may improve cognitive performance in some areas. Let me explain.
Exercise and Dementia: Maybe Exercise Does Improve Dementia
The dementia study I reported on Tuesday found that exercise improved fitness levels in those with dementia but didn’t improve cognitive function; in fact, it found that exercise may even cause a cognitive decline. However, as mentioned, we’ve seen many conflicting studies on the topic of exercise and dementia.
Now, another recent study has provided a different conclusion. In this meta-analysis, researchers aggregated and analyzed 98 studies to determine how exercise affected older subjects both with and without cognitive impairment. In both groups, they found that exercise improved cognitive performance. Specific improvements included speed of thought processes, attention, and executive function (planning, execution of plans to achieve goals, judgment, etc.). Further, these improvements were achieved after 52 total hours of exercise, which included aerobic activities, strength training, or “mind-body exercises.”
One of our fellows who is now heading up the Regenexx Miami site (Jamil Bashir, MD) first told me about Lion’s Mane a few years back. I was just beginning to get my first middle-aged brain hiccups. You know the ones, where you can’t seem to think of the name of something. Jamil told me that ever since he read some papers on a mushroom extract that had been shown to help nerve cell regrowth, he had been taking Lion’s Mane and that I should try it. I eventually acquiesced, and I now swear by it. No more middle-aged brain hiccups! I take one capsule a day of this stuff. I also exercise regularly.
The upshot? So which study do you trust? In science, the results of a meta-analysis always trump a single study. Hence, I would say that exercise helps dementia! So even if your brain is starting to get a little dull, get out and exercise!