Dementia is what many of us fear most, and the effective risk is largely related to age. The statistics say that at 65 years of age, only 2% have dementia. But this figure doubles with the passage of each five year period. By 90, the risk of having dementia is about one in four. Because of the “survivor effect” (those with the fewest risks will live to old age), the subsequent risk no longer increases at this rate.
There is no guarantee that dementia can be avoided, whatever we do. But what does the evidence say about what strategies can reduce the risk? Genes account for only a small percentage of those with dementia, especially among the elderly.
There is now evidence that the risk can be reduced, and that this will lead to fewer people with dementia. In fact, we think that if the onset of dementia could be delayed by five years, then the numbers would be halved (Dementia Risk Reduction, prepared for Alzheimer’s Australia, 2007).
Despite much controversy in recent years about the exact cause of Alzheimer’s disease- the most common form of dementia in the western world- it turns out that the factors which protect against heart disease also protect against dementia. The UK Blackfriars consensus produced this year suggested that within two decades up to 20% of predicted new cases of dementia could be prevented with lifestyle alterations designed to reduce blood pressure, obesity, cholesterol and diabetes.
So what can we do to minimise the risk of developing dementia?
The brain is arguably the most important organ and should be treated with respect at all times. “Getting knocked out” sounds bad, and it is. We are now aware that episodes of concussion are bad for the brain and there are reports that head injuries contribute to dementia. Protect your brain, and not just from toxic substances.
It’s never too early to start with life style changes. Both physical and mental activity are critical, and the earlier they start, the better. Regular is good- say 30 minutes every day of sustained physical exercise. Patterns established in youth are harder to break in old age. When it comes to mental exercise, repetition of familiar tasks is not particularly useful (such as Sudoku or crosswords); there must be real stimulation and challenging to the brain. Learning a language or taking a university course in a new field is what’s needed.
Connectivity is the new buzz word for dementia. This relates to the structure of the brain (how nerves connect with each other) and the disruption of neuronal connectivity is emerging as a key component in the impairment of brain function. But it also relates to social connections. People don’t thrive in isolation and neither do brains. As we age, we lose social connections (people die) so it’s necessary to have a large social network when we are younger. Being with people- having relationships, joining groups, developing interests which involve human contact- these will all improve brain function and help to reduce the dementia risk. Ideally, you should have friends who are younger than you are, but at least a mixture of ages.
Nurturing the senses is about maximising the inputs to the brain. Good vision and hearing are among the important predictive factors for a good memory in old age. Fifty percent of older people have an incorrect prescription for their spectacles, and while most very elderly people have some deafness, hearing aids are often not worn. Now is the time- however young or old you are- to have a check and correct any sensory deficits as soon as possible.
What should you eat? Moderation and balance will usually do the trick. Having a healthy weight before old age is critical: in older age weight loss means losing muscle, and this is a sure way of triggering falls, impairing the circulation and immune function. For most older people, care needs to be taken to maintain weight, and to have protein at the centre of every meal. Salt is bad for the brain as it contributes to hypertension which itself causes damage. Fats are essential, but are best in balance; avoid saturated fats as these may double the risk of dementia. Fruits and vegetables are associated with longevity, but also promote good bowel function. Constipation in old age is the enemy of health, happiness and functioning well, each of which helps us to live the dementia journey better. Broccoli and cauliflower also contain Vitamin E which is thought to be protective against dementia. If you need more guidance, the Mediterranean diet has recognised benefits.
Alcohol in moderation may be protective, but with excessive amounts (regular consumption in excess of two drinks a day or four in a single session) come increased risks for hypertension, cardiovascular disease and dementia. Binge drinking may increase the risk of dementia three fold after 65.
Smoking is a serious risk for a range of illnesses, and if you survive cancers, chronic lung diseases (especially emphysema) and vascular disease (heart attacks and strokes) then dementia is also more likely in your old age.
Regular blood pressure checks and careful control are essential, as hypertension is the enemy of brain health. Avoiding diabetes, similarly dangerous for brains, means a healthy diet, weight control and regular screens. See your doctor if there are any new symptoms, especially lethargy, blurred vision, increased hunger, unexplained weight loss or increased thirst. If you have diabetes, keep the sugars under control.
Your psyche should be as important to you as your physical health. The responsibility for your state of mind rests with you, and while stress might not be avoidable, how you deal with it is up to you. If you need help, get it. Whether you get dementia is not up to you. But there are ways to reduce the risk, and to make the journey less traumatic if you are unlucky. What is up to you, is what you know (keep up to date) and your attitude to your health (be positive). Reducing your risks for dementia is a lifelong undertaking and will make you a happier and healthier person.
Jane Tolman is Director of Aged Care, Royal Hobart Hospital.