Dementia. We all make jokes about it: grey nomads put ‘Adventure Before Dementia’ stickers on the back of their Winnebagos; middle-aged people ascribe forgetting a familiar name or fact to ‘having a senior moment’; and the ‘silly old bugger’ character is a standard fixture of TV shows and movies.
But if you’ve ever watched a loved one succumb to the ravages of dementia – the progressive loss of the ability to care for themselves, carry on a conversation, connect with family and friends, and eventually to even remember who they are, as their entire personality disintegrates – you know that dementia is the most unfunny experience ever, for all concerned.
I’ve lost my mother-in-law and several aunts to this horrific process, and chances are that you know at least one person who has been affected by it too.
Contrary to popular mythology, dementia is not a natural part of aging. It’s a group of over 100 diseases (including Alzheimer’s disease, vascular dementia, Lewy Body disease, frontotemporal dementia and alcohol related dementia) that damage the brain, causing progressive loss of its functions.
10% of Australians aged over 65, and a startling 31% of those over 85, are living with dementia. And when I say that they’re living with it, the reality is that all of those around them – their partner, children, friends and the medical and aged care systems – are living with it too. In fact, over 50% of residents of government-funded nursing homes suffer from dementia.
The economic, social and emotional costs of caring for the 342 800 Australians were living with dementia in 2015, are staggering and are only set to rise: because our population is getting larger and, on average, older, the number of dementia sufferers is projected to reach almost 400 000 by 2020, and roughly 900,000 by 2050.
With such a massive potential market share, it’s not surprising that pharmaceutical companies have got busy developing drugs to treat dementia, but the results so far have been pretty underwhelming. None of the drugs currently used are curative: they don’t stop the underlying disease process, they don’t prolong lifespan and they don’t change the outcome of the disease.
Their benefits – when they’re experienced at all, which is in the minority of patients – are so insignificant that in 2005 the British National Institute for Clinical Excellence (NICE) advised the UK’s National Health Service to stop paying for the drugs for most Alzheimer’s patients, although subsequent hard lobbying from the drug industry and the patient front-groups that they fund (unbeknownst to most of the public who donate to these groups in good faith), caused these guidelines to be watered down.
In the absence of effective medical therapy, many people hope that simply ‘keeping their brains active’ by doing crossword puzzles, reading, learning a foreign language and so on, will help to stave off dementia. There is some evidence of benefits of this strategy, both for healthy older people and those with mild cognitive impairment (MCI). Think of MCI as ‘pre-dementia’ – an intermediate stage between normal cognitive function and dementia, which puts you at high risk of developing dementia.
More formal types of cognitive training, either delivered by health professionals or computers, have also shown some benefit for both cognitively healthy people and those with MCI, although results have been mixed.
But keeping your body active may do even more good for your brain than just stimulating your grey matter, according to a team of Australian researchers who compared the effectiveness of a cognitive training program (a structured, multidomain computerised intervention) with a high intensity progressive resistance training program (supervised weight training sessions using gym machines to work the major muscle groups, at high intensity, using progressively greater weights as participants’ strength increased), in staving off the onset of dementia in people with MCI.
The researchers randomised 100 adults who had been diagnosed with MCI into 1 of 4 groups:
- Cognitive training + a ‘sham’ exercise intervention (stretching and seated calisthenics)
- Progressive resistance exercise + a ‘sham’ cognitive intervention (watching short documentaries and answering questions about them)
- Combined cognitive + progressive resistance training
- Control group – sham cognitive + sham exercise interventions
and then followed them up for 18 months.
What they found was truly fascinating. As expected, the people assigned to the exercise-only group had dramatic improvements in their executive function. Executive function describes the higher-level cognitive skills that we use to control and coordinate our other cognitive abilities and behaviours, in order to plan and carry out goal-oriented behaviour (which covers anything from getting dressed to planning a space mission); decline in executive function is a cardinal sign of dementia.
But contrary to their expectations, the exercise-only group actually did substantially better than the combined group. As in, 60% better at 6-month follow up, and a whopping 74% better at 18 months. The researchers weren’t sure why this happened, but speculated that the combined intervention was so mentally and physically challenging, it may have caused excessive stress, or made participants less likely to engage in home or community-based activities that promote cognitive health.
Resistance training also improved the proportion of people who achieved normal scores on a test of global cognitive function (overall thinking ability), whereas cognitive training had no effect.
The take-home message is that if you want to stave off both physical and mental decline as you get older, you need to work that body hard – those ‘gentle exercise for seniors’ classes just won’t cut it. But older women, in particular, often feel quite intimidated by the idea of resistance training. Of course, you don’t need to go to a gym and compete for the weights machines with steroid-popping, sweaty muscle-jockeys.
Small exercise studios run by exercise physiologists, or experienced personal trainers who have completed additional education in training older people, are ideal for those who’ve never pumped iron before. You may even be eligible for a Medicare referral to an exercise physiologist; ask your GP.
Remember that your resistance program needs to be challenging – if you can easily do 10 repetitions of an exercise, you’re not lifting a heavy enough weight – and progressive – as soon as an exercise starts to get easier, you switch to a heavier weight, and/or a more difficult variation of the exercise.
By the way, cardiovascular disease is a major risk factor for developing Alzheimers’ and vascular dementia, the two most common forms of dementia, and it’s highly probable that the same dietary factors that cause heart disease also contribute to brain disease. As the old saying goes, you can’t out-exercise a bad diet, so be sure to couple your resistance exercise program with a heart-healthy eating plan.