Читать книгу Pathy's Principles and Practice of Geriatric Medicine - Группа авторов - Страница 344

The wave of ageing elders is also placing many more people at risk for cognitive impairment and dementia. It is estimated that 100 million people will have dementia by 2050, and this will cripple a fragile healthcare system where people live for an additional 8‐20 years after the diagnosis requiring caregivers and family support. Thus, prevention strategies are needed to delay onset and maintain independence in older adults. Nutrition may play a significant role in preventing and even managing dementia, including Alzheimer’s disease. An abundance of evidence supports nutrition for the prevention of age‐related cognitive decline and dementia, but there are few specific recommendations due to inconclusive clinical trial results. There have been several interventions testing single or a few nutrients for the prevention of cognitive decline. These include the homocysteine‐lowering B vitamins (B6, B12, and folate), vitamin E (alpha tocopherol), and the omega‐3 fatty acids (docosahexaenoic acid). Next‐generation clinical trials are underway that are more targeted and comprehensive, offering further hope of recommendations in the future (clinicaltrials.gov: NCT01953705, NCT02817074).

Studies of dietary patterns related to age‐related cognitive impairment and dementia are limited, perhaps because of the added challenge of assessing this relationship when the outcome of interest interferes with the integrity of the measure of diet (cognitive impairment effects on recall of dietary intake). Three primary dietary patterns have been consistently associated with less cognitive decline and reduced risks for dementia, including the Mediterranean style diet, Dietary Approaches to Stop Hypertension (DASH), and a hybrid of both diets (Medi‐DASH diet for Neurodegenerative Delay [MIND]) (Table 12.1). The MIND diet developed by Morris includes greater consumption of food groups specifically associated with cognitive health and dementia prevention. These include green leafy vegetables, nuts and seeds, berries, beans and whole grains, fish, poultry, olive oil, and wine. The diet also reduces red meats, butter and stick margarine, cheese, pastries, sweets, and fried or fast food. The Mediterranean diet shown to be neuroprotective is rich in fruits, vegetable, whole grains, olive oil, and everyday consumption of fermented dairy, nuts, seeds, herbs or spices, with an emphasis on plant protein (legumes) and seafood rather than red meat, wine in moderation, and daily consumption of herbal teas. Many of these observations have been confirmed using nutrient biomarkers that reflect the concentration of nutrients enriched in such dietary patterns (Table 12.1).