Important Steps and Measures for Prevention of Alzheimer's?
There is no evidence that supports any particular measure as being effective in preventing Alzheimer's disease. Global studies of measures to prevent or delay the onset of Alzheimer's disease have often produced inconsistent results.
Epidemiological studies have proposed relationships between certain modifiable factors, such as diet, cardiovascular risk, pharmaceutical products, or intellectual activities, among others, and a population's likelihood of developing Alzheimer's disease. Only further research, including clinical trials, will reveal whether these factors can help to prevent Alzheimer's disease.
Cardiovascular risk factors, such as hypercholesterolaemia, hypertension, diabetes, and smoking, are associated with a higher risk of onset and worsened course of Alzheimer's disease. Blood pressure medications may decrease the risk. A review found that the use of statins, which lower cholesterol may be of benefit in Alzheimer's and other dementias but not in vascular dementia.
Long-term usage of non-steroidal anti-inflammatory drugs (NSAIDs) were thought in 2007 to be associated with a reduced likelihood of developing Alzheimer's disease. Evidence also suggested the notion that NSAIDs could reduce inflammation related to amyloid plaques, but trials were suspended due to high adverse events.
No prevention trial has been completed. They do not appear to be useful as a treatment, but as of 2011 were thought to be candidates as presymptomatic preventives. Hormone replacement therapy in menopause, although previously used, may increase risk of dementia.
Evidence suggests that higher education and occupational attainment, and participation in leisure activities show a reduced risk of developing Alzheimer's, for of delaying the onset of symptoms.
This is compatible with the cognitive reserve theory, which states that some life experiences result in more efficient neural functioning providing the individual a cognitive reserve that delays the onset of dementia manifestations.
Education delays the onset of Alzheimer's disease syndrome without changing the duration of the disease. Learning a second language even later in life seems to delay the onset of Alzheimer's disease. Physical exercise is associated with decreased rate of dementia. Physical exercise is also effective in reducing symptom severity in those with Alzheimer's disease.
Diet is seen to be a modifiable risk factor for the development of dementia. The Mediterranean diet, and the DASH diet are both associated with less cognitive decline. A different approach has been to incorporate elements of both of these diets into one known as the MIND diet. These diets are generally low in saturated fats while providing a good source of carbohydrates, mainly those that help stabilize blood sugar and insulin levels. Those who eat a diet high in saturated fats and simple carbohydrates (mono- and disaccharide) have a higher risk.
Raised blood sugar levels over a long time, can damage nerves and cause memory problems if they are not managed. Nutritional factors associated with the proposed diets for reducing dementia risk, include unsaturated fatty acids, antioxidants vitamin E, vitamin C, and flavonoids, vitamin B, and vitamin D.
The MIND diet may be more protective but further studies are needed. The Mediterranean diet seems to be more protective against Alzheimer's than DASH but there are no consistent findings against dementia in general. The role of olive oil needs further study as it may be one of the most important components in reducing the risk of cognitive decline and dementia. In those with celiac disease or non-celiac gluten sensitivity, a strict gluten-free diet may relieve the symptoms given a mild cognitive impairment. Once dementia is advanced no evidence suggests that a gluten-free diet is useful.
Conclusions on dietary components have been difficult to ascertain as results have differed between population-based studies and randomised controlled trials. There is limited evidence that light to moderate use of alcohol, particularly red wine, is associated with a lower risk of Alzheimer's disease.
There is tentative evidence that caffeine may be protective. A number of foods high in flavonoids such as cocoa, red wine, and tea may decrease the risk of Alzheimer's disease. A number of studies have looked at the possible role of minerals such as selenium, zinc, and copper.
Omega 3 fatty acid supplements from plants and fish, and dietary docosahexaenoic acid (DHA), do not appear to benefit people with mild to moderate Alzheimer's disease. Curcumin as of 2010 had not shown benefit in people even though there is tentative evidence in animals. There is growing evidence (2020) for the neuroprotection offered by the use of cannabinoids in Alzheimer's and other neurodegenerative disorders. However, further population studies are recommended to see this use beyond experimental.