Dementia - Prevention

Dementia - Prevention

Dementia is difficult to prevent because what causes it often is not known.

However, people who have vascular dementia may be able to prevent future declines by lowering their risk of heart disease and stroke. Even if you don't have these known risks, your overall health can benefit from these strategies:

• Treat or prevent high blood pressure. To do this, you may need to take medicines or you may be able to get results from lifestyle changes such as losing excess weight, exercising, limiting alcohol, cutting back on salt, quitting smoking, and eating a low-fat and low-saturated-fat diet. For more information, see the topic High Blood Pressure (Hypertension).
• Do not smoke.
• Stay at a healthy weight. This also reduces your risk of diabetes, another risk factor for dementia.
• Keep your cholesterol in the normal range. Total cholesterol should be less than 200 mg/dL. For more information, see the topic High Cholesterol.
• Get plenty of exercise. Try to do at least 2½ hours a week of moderate exercise. one way to do this is to be active 30 minutes a day, at least 5 days a week. It's fine to be active in blocks of 10 minutes or more throughout your day and week.¹²
• Stay mentally alert by learning new hobbies, reading, or solving crossword puzzles.
• Stay involved socially. Attend community activities, church, or support groups.

In people who already have had a stroke, treating high blood pressure reduces the risk of another stroke by 20%. Taking aspirin to prevent blood clots lowers the risk of another stroke by 17%.¹³ For more information on how to reduce your risk for stroke, see the topic Stroke.

Some older people develop symptoms that look like dementia but are the result of taking medicines that don't work well together. You may be able to avoid this problem by making sure your doctor knows about all medicines-both prescription and over-the-counter-and all vitamin, herbal, and dietary supplements you take.

Research

• One study found that older adults who regularly participated in leisure activities that required mental effort reduced their risk of dementia. Reading, playing board games, playing a musical instrument, and dancing were all found to be helpful, but most likely any hobby that keeps the brain active would be beneficial.¹⁴
• Some evidence suggests that light to moderate alcohol use (1 to 6 drinks a week) may reduce the risk of dementia in older people.^{15, 16} Since heavier drinking can cause dementia, alcohol use is a widely debated issue.
• One study found that people age 50 or older who took cholesterol-lowering medicines called statins reduced their risk of developing dementia.¹⁷ More recent studies have not found that statins reduce the risk of dementia. But these studies were of people age 65 and older.^{18, 19} Whether taking statins might help people who start them at a younger age is not known.
• Hormone replacement therapy (HRT)-a combination of estrogen and progesterone-was once believed to provide protection from dementia or cognitive impairment. But the Women's Health Initiative found that HRT actually increased the risk for Alzheimer's disease and other dementias in women age 65 and older who took it for more than 4 years.⁴ Estrogen alone (estrogen replacement therapy) had similar effects.⁵ Whether either of these therapies might help reduce the risk of later dementia when used around the age of menopause is not known.⁶

 

 

Lifestyle

 Mental activity

Main article: Brain fitness

"Use it or lose it" might be applied to the brain when it comes to dementia. Intellectual activities help keep the mind in shape in the older days. Activities such as reading, playing cards and board games and playing a musical instrument prevent dementia of both Alzheimer's and vascular dementia.^[1] The risk decreases proportionally to the frequency of activity.^[1]

Not only activities during spare time seem to prevent dementia. The kind of occupation also matters, especially during the thirties, forties and fifties.^[1] A good job in this case is any mentally demanding one.

Why activity contributes to prevent dementia could be explained by a "brain reserve" built up by the brain: additional connections between neurons are created, connections more resistant to the deterioration seen in dementia.^[1]

 Physical activity

Since vascular dementia is the second most common form of dementia (after Alzheimer's disease), decreasing risk factors for cerebrovascular disease also decreases the risk factors for dementia. Thus, physical exercise, having good blood cholesterol, healthy body weight and blood pressure lowers the risk of developing dementia.^[1] An active lifestyle can almost halve the risk compared to a sedentary one.^[1]

The effect of physical activity is not limited to vascular effects. For instance, it can give rise to new neurons in the brain, as well as releasing a substance that can protect them.^[1]

Some studies say Alzheimer's and other dementias may be caused by high blood pressure, since it can cause blood vessel damage by constricting them.^[2][3]

 Diet

Obesity increases the risk of any dementia and Alzheimer's disease in particular.^[1] The effect of alcohol on the risk of dementia is a J-shape.^[4] High alcohol consumption increases the risk of dementia^[5] while low alcohol consumption may be protective.^[4] It is not protective however for vascular dementia and overall cognitive decline.^[4] The effects of omega-3 fatty acid in the prevention of dementia is uncertain.^[6] Vegetables and nuts may be of benefit,^[1] because of their high content of polyunsaturated fats. Non-fish meat, on the other hand, increases the risk of Alzhemer's,^[1] because of its high content of saturated fat.

 Sleep pattern

Prolonged, more than nine hours, sleep duration (night-time sleep and daytime napping) may be associated with an increased risk of dementia.^[7]

 Medication

 Hypertension medications

The etiology of vascular dementia includes hypertension, and thus, lowering blood pressure with antihypertensives has a positive effect in the prevention of dementia, just as physical activity.

A study has shown a link between high blood pressure and developing dementia. The study, published in the Lancet Neurology journal July 2008, found that blood pressure lowering medication reduced dementia by 13%.^[8]

Furthermore, antihypertensives lowers the risk of not only vascular dementia, but also of developing Alzheimer's disease, especially when using potassium-sparing diuretics.^[1]

 Anti-diabetic drugs

Diabetes mellitus is a risk factor for vascular dementia, and is thus lowered with anti-diabetic drugs.^[9]

Besides, Rosiglitazone (Avandia) improves memory and thinking ability to people with mild Alzheimer's disease. The mechanism of the effect might be due to the ability of the drug to reduce insulin resistance.^[1] Thus, less insulin needs to be released to achieve its metabolic effects. Insulin in the bloodstream is a trigger of amyloid beta-production,^[9] so decreased insulin levels decrease the level of amyloid beta. This leads to less formation of amyloid plaques seen in Alzheimer's disease.

 NSAIDs

Non-steroidal anti-inflammatory drugs (NSAIDs) can decrease the risk of developing Alzheimer's and Parkinson's diseases.^[1] The length of time needed to prevent dementia varies, but in most studies it is usually between 2 and 10 years.^{[10][11][12][13][14]} Research has also shown that it must be used in clinically relevant dosages and that so called "baby aspirin" doses are ineffective at preventing and treating dementia.^[15]

Alzheimer's disease causes inflammation in the neurons by its deposits of amyloid beta peptides and neurofibrillary tangles. These deposits irritate the body by causing a release of e.g. cytokines and acute phase proteins, leading to inflammation. When these substances accumulate over years they contribute to the effects of Alzheimer's.^[16] NSAIDs inhibit the formation of such inflammatory substances, and prevent the deteriorating effects.^[17][18][19]

 Vaccine

There is yet no vaccine against dementia.^[1] Such a vaccine could activate the body's own immune system to combat the beta amyloid plaques in Alzheimer's disease. one problem to overcome is overreaction from the immune system, leading to encephalitis.^[1]