at present, there are about 4700 cases of dementia worldwide and are expected to exceed 100 million by 2050, of which 68 per cent are concentrated in developing countries . Alzheimer's disease (Alzheimer's disease, AD) is the most common type of dementia, accounting for about 60% to 80%.
in the past 30 years, with the improvement of living environment, education and medical level, the incidence of AD has decreased in some European and North American countries. This suggests that AD is similar to other chronic diseases, there are many controllable risk factors, early intervention may delay the occurrence and progression of the disease . Both the Lancet (Lancet) and the Journal of the American Medical Association (JAMA) suggest that active lifestyle intervention can reduce the incidence of dementia by as much as 1.
in this paper, based on the research evidence, the potential preventive measures for AD are summarized as follows:
cardiovascular and cerebrovascular diseases (mainly hypertension, hyperlipidemia, diabetes, obesity) are associated with the increased risk of dementia, including AD. Long-term exposure to the above risk factors will lead to arteriosclerosis, and then lead to insufficient cerebral blood supply, affecting the clearance and transport of AD-related pathological substances. Among them, middle-aged people with high blood pressure and obesity and AD evidence is more sufficient, but the elderly suffering from high blood pressure and obesity, and AD does not seem to have much relationship.
actively control the above-mentioned AD-related vascular risk factors, which is expected to delay or reduce its occurrence. Studies have shown that keeping systolic blood pressure below 120mmHg reduces the risk of (MCI) for mild cognitive impairment. Type 2 diabetes can significantly increase the risk of AD. Therefore, the control of blood pressure, blood glucose and blood lipids can effectively reduce the risk of AD, including regular medication, strict monitoring, exercise, healthy diet, quitting smoking and so on.
the elderly often have a variety of somatic diseases, including systemic diseases (such as liver insufficiency, renal insufficiency), metabolic diseases (such as vitamin deficiency, etc.), endocrine diseases (such as hyperthyroidism, hypothyroidism, etc.), which may lead to the decline of cognitive function. Active treatment of primary disease can improve cognitive function.
the bad lifestyle that can increase the risk of AD mainly include smoking (including secondhand smoke), alcoholism, lack of physical exercise and poor sleep status.
especially if smoking (especially middle-aged smoking) exceeded 20 cigarettes per day, the risk of AD increased by 157%. Smokers had a 50% to 80% increased risk of AD compared with non-smokers, and secondhand smoking also increased the risk of AD .
the above lifestyle is the most easy to change. It is suggested that people at high risk of AD should quit smoking, limit alcohol, exercise actively and get enough sleep.
in 2013, the International Conference on Nutrition and brain issued dietary reference guidelines for the prevention of AD, which mainly include: vegetarian diet, vitamin E and B supplementation, avoiding the intake of saturated fatty acids and trans fatty acids, and avoiding excessive metal intake (such as avoiding iron and copper contained in multivitamins) .
some healthy eating patterns are widely regarded. For example, the Mediterranean diet can reduce cognitive impairment and delay the progression of mild cognitive impairment (MCI) to AD, is a more recommended diet pattern. The Mediterranean diet advocates eating large amounts of vegetables, fruits, grains, legumes and fish. Olive oil is recommended as the main source of fat and moderate drinking of red wine is recommended, but excessive drinking and intake of more meat and dairy products are not recommended.
the study found that people with low level of education and less communication with others had a higher risk of AD . Education can improve a person's cognitive reserve ability and be more tolerant to aging or pathological changes in AD.
increasing the number of years of education (such as studying according to one's own situation, going to college for the elderly), actively socializing, learning musical instruments/foreign languages, etc., can combat the occurrence of AD symptoms by increasing the ability of cognitive reserve. It is suggested that the elderly who play puzzle games and cards reduce the risk of AD by 47%. Trying to learn a foreign language can strengthen the overall cognitive ability and delay the development of AD for an average of 4 years .
families can give old people the opportunity to try new things, such as teaching them to use mobile phones, take them to social activities, and often communicate with their relatives and friends.
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