People want to stay sharp as they age. So what’s the best way to prevent mental decline? It may be that mental exercises provide the most reliable way to stay sharp.
A recent review looked at 32 previous trials which examined therapeutic attempts to slow mental decline in healthy older adults.
The results showed that estrogen therapy made mental functioning worse, while other hormone, pharmaceutical and supplement therapies yielded inconsistent results.
Mental function consistently improved in trials using mentally challenging exercises.
Ravi Naqvi, MD, from the Division of Geriatric Medicine at the University of Toronto in Canada, led an investigation into ways to keep the minds of healthy older adults sharp through the aging process.
“Given the increase in the aging population, the prevention of cognitive decline in healthy older adults deserves close attention. Mild cognitive impairment affects 10 to 25 percent of people over the age of 70 years,” the authors said.
This review did not include mental decline at the severity involved with dementia. Rather, this review looked into the way older, but otherwise healthy, adults worked to preserve their mental sharpness as they aged.
For the review, the authors searched medical study databases and found 32 published randomized controlled trials on preventing mental decline in people 65 years of age and older.
The researchers noticed there were no studies that showed any prescription medications helped prevent mental decline in healthy older adults. They did find evidence that certain medications, including hormone therapy and anti-inflammatories, did mental harm.
Cholinesterase inhibitors, such as Donepezil, and N-methyl-D-aspartate (NMDA) receptor antagonists, such as memantine, have been used to slow mental and functional decline in patients with dementia.
One of the 32 trials reviewed showed a slight improvement in 10-week recall ability in patients that were given donepezil. But the other two trials testing donepezil and memantine “showed no improved memory or cognition,” according to authors.
Estrogen therapy was studied in seven of the 32 trials, four of which followed 10,426 patients for four to five years. The results of those trials showed an increase in dementia and a decrease in mental functioning.
Testosterone therapy was studied in three trials. Minor memory benefits were found after three months in one study. But another trial showed worsened short-term memory and the other trial showed no changes at all.
Three trials tested the effects of dehydroepiandrosterone (DHEA), a natural hormone. The trials included 317 patients and showed no effects whatsoever during the follow-up periods.
Two trials tested the effects of the herbal supplement, ginkgo. A total of 348 participants showed no changes in mental functioning during follow-up.
Trials also looked at vitamin B6, vitamin E, folic acid and omega-3 fatty acids, none of which showed any changes in the mental functioning of participants during follow-up.
Candesartan, a blood pressure medication, showed no changes in the mental function of nearly 5,000 participants over four years.
The non-steroidal anti-inflammatory drugs (NSAIDs), naproxen and celecoxib, were tested on 2,500 patients over three years. “Marginal decline in memory” was found in participants in the NSAID trial.
Different types of physical exercises were tested in three of the trials. Resistance training and balance exercises with flexibility and relaxation training did not render improvements in mental functioning in the participants.
Aerobic exercise groups did show improved higher-level mental function, but not memory function.
The best improvements in mental functioning were found in the trials testing “cognitive training,” or mental exercises to maintain reasoning, speed and memory. One of the trials used computerized cognitive training.
Cognitive training trials, which included 3,321 participants, improved memory function most consistently of all of the trials.
The authors noted a limitation to this review was the short follow-up periods of a few weeks to only five years. That is to say, certain therapies could take much longer than 10 years to improve or reduce mental functioning.
“This review highlights that despite the importance of cognitive impairment, there is not a substantial body of literature addressing how it may be prevented,” the authors concluded.
This review was published in April in the Canadian Medical Association Journal.
No outside funding was declared. No conflicts of interest were found.