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Opinion: On Living Longer

Memory loss in healthy older adults is on the rise, as are preventive treatments—but there is little evidence that these remedies are effective.

By | June 24, 2013

WIKIMEDIA, JORGE ROYANAs science, technology, and health care continue to advance, our population continues to live longer. With the increasing number of seniors, diseases prevalent in this group will clearly increase as well. The prevalence of mild cognitive impairment (memory loss without any functional decline) is about 10–25 percent in adults over the age of 70. Approximately 10 percent of these individuals progress to a dementia syndrome each year. Estimates have the number of people living with dementia doubling over the next 25 years.

There has been a lot of emphasis placed on preventative health in recent years. Whether it is preventing strokes, heart attacks, or any other disease, it is clear that prevention saves time, money, and lives. We recently published a review on the high-quality medical studies aimed at preventing cognitive decline in the aging population (CMAJ, .

We studied all of the English language medical literature for randomized controlled trials in healthy older adults and found only 32 that met our criteria of including only healthy older adults with no current signs of cognitive decline.

One category of interventions we found was medications marketed for dementia. Donepezil, a cholinesterase inhibitor which is used in the treatment of dementia, has led to improvement in some, but not all, measures of memory, but other studies have failed to show any improvement at all.

Hormonal therapies, such as treatment with estrogen, has similarly had mixed results. A meta-analysis published in 1998 showed an almost 30 percent lower dementia incidence in those on estrogen therapy. The trouble with all prior studies had been that they were based on retrospective or case-control data; there were no randomized controlled trials to look at the effects of estrogen specifically. In 2003, the Women’s Health Initiative in Memory Study (WHIMS) took the first major step by publishing results of a study investigating more than 10,000 women to look at the effects of estrogen and progesterone on memory, and actually found an increase in the rates of dementia in those on therapy by about 80 percent. Treatment with testosterone or DHEA has also shown inconsistent results.

Herbs and vitamins are widely advertised for preventing memory loss. The literature provides no such evidence that they work, however. Two well-designed trials of ginko showed no benefit in healthy older adults, and vitamins B6 and E, folic acid, and omega 3 fatty acids all demonstrated similarly equivocal results compared to placebo. Researchers have even tested the effects of an antihypertensive medication (candesartan) and two anti-inflammatories (celecoxib and naproxen), and found that none were beneficial and the anti-inflammatories even caused marginal harm.

In fact, the most consistent evidence in preventing memory loss in healthy older adults comes from three independent studies which all used various forms of cognitive training. One study used in-person training activities and the other two used differing computer-based training protocols. All 3 found their interventions improved memory in healthy older adults; one of the studies extended out to 5 years.

Physical exercise has also shown some evidence of boosting memory, but the evidence is less convincing. One trial looking at resistance training found an improvement in some measurements of short-term and long-term episodic memory, but two other trials did not find consistent benefits.

One major limitation of our review was including only English language literature. By not including studies published in other languages, we have the potential of missing positive studies—especially in the areas of alternative medicine where we know there is a possible implicit negative bias in many English language journals.

There is also the risk that some of the studies included in our review were looking for subtle differences that would not be seen with one simple measurement or involved data dredging—in which researchers look for any positive outcome so that their study could be reported as positive and have a higher likelihood of being published. Nevertheless, it is clear that there is an unmet medical need to stem the increase in cognitive decline in older individuals.

For now, the best advice we can give is to stay mentally active, exercise as much as you can (for its countless other benefits), and if you’re on a supplement or medication to prevent memory loss, talk to your doctor about it because you (and your wallet) might be having side effects without any clear benefit.

Raza M. Naqvi completed medical training from University of Western Ontario and Internal Medicine training from University of Toronto and is currently doing Geriatric Medicine Fellowship at the University of Toronto, with a focus on memory disorders, dementia, and ethics.

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Avatar of: 85 Years to Go!

85 Years to Go!

Posts: 1

June 25, 2013

Age:  73

Future: 85 Years to Go!

My personal experience under the care of a competent Naturopath is that vitamins, minerals, diet changes and supplements specified on the basis of blood tests work like a charm.

We finally figured out that a myriad of symptoms, including dementia and memory loss, tremors, spasms, craps, burning skin, etc. might be caused by heavy metals toxicity, gluten intolerance, and possibly GMO foods like corn and soybeans. Specifically, arsenic and mercury were at toxic levels.

I now am on a non-inflammatory diet. I am chelating with chlorella. I take B-12 and Magnesium. There are more pills, of course, but these supplements seem to be a key. The process takes time. We began chelation in August, 2012.

I feel better and have more energy than I did 20 or more years ago. My brain is as sharp as it used to be. My mind, like the bear trap I expect it to be.

Even my so-called prostate issues are improving and I'm sleeping for longer stints at night - up from 2 hour to 4 hour intervals. Frankly, I am amazed!

Sure, this is anecdotal. But if one extrapolates from my experience, many of the "chronic" conditions we associate with aging have to do with diet, with the gut's bacterial environment, and with the interaction of foods, environment and genes. The genetic component makes diagnosis and treatment specific to the person.

The idea that you treat a symptom with a pill is limiting and creates a Scotoma to seeing a bigger picture, discovering an actual cause, and putting body and mind back on track.

I stay as far away from conventional medicine and from hospitals as I can.

Avatar of: bivv

bivv

Posts: 1

June 25, 2013

I feel much better when I cut gluten and sugar and milk out. Much more alert and more energy. I feel not enough tests are doing on the impact that diet has on general health. Plus recently it has been found that mini starve periods help the brain and also coconut oil, yet none of these were mentioned. I agree some things are hyped up by the press and stay in many people's minds like ginko. But to use this to assume there is NOTHING that diet is likely to do, is wrong. Also you say exercise as much as you possibly can. Well you need to be aware that this uses up minerals, and we need to take more the more youweexercise. So either eat lots of veg or supplment. Lots of veg is better as it also contains many phytonutrients, which science has only just started to understand and study. And in long term diseases it takes time for studies to prove that certain foods aid in prevention, as they work over a lifetime of protecting us. You can try and study the existing populations based on their diet but this is fraught with difficulties as there are many factors involved and it is hard to pick out which is the cause behind the health (or poor health) of many populations. And often it is just eatting plenty of veg and not eatting processed foods, rather than any one food as you mention. No one food will make us well, but FOOD can make us well, if we stick to eatting food, and not the processed.. And much less funding is provided for this than is for pharma style drugs where there could be billions made if "proof" is provided of some benefits. 

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