Alzheimer disease (AD) prevalence in the United States currently exceeds 5 million, and the Alzheimer’s Association estimates a US prevalence of 16 million by the year 2050 unless an effective treatment is developed. Increasing age is still the leading risk factor for AD, with a prevalence of 42% by age 82 years. Other nonmodifiable risk factors include female sex, positive family history, and presence of the apolipoprotein E 4 allele.
At present, only four FDA-approved medications are available for memory and behavioral AD symptoms. Disease-modifying treatment trials have been unsuccessful, although several new trials are underway and research continues. Prevention strategies are therefore essential and are now facilitated by advances in diagnostic criteria, biomarker development, and greater understanding of the biophysiologic underpinnings of AD.
Risk-factor prevention should target diabetes mellitus and insulin resistance, obesity, metabolic syndrome, hypertension, hypercholesterolemia, cerebrovascular disease, depression, psychological and physiologic stress, traumatic brain injury, sleep-disordered breathing, smoking, alcohol abuse, high blood pressure, renal disease, alcohol and tobacco use, high cholesterol, coronary heart disease, sedentary life style, and diet. These potentially modifiable risk factors, when combined, account for more than 50% of AD risk, based on observational studies, and many of these risk factors do not appear to affect amyloid tau proteins. In sporadic and genetic forms of AD, pharmacologic trials of antiamyloid therapies are ongoing.
Modifiable factors appearing to protect against AD include cognitive reserve and mental activity, educational attainment and lifelong learning, cognitive leisure activities, physical activity and exercise, social engagement, mindfulness and wellness activities, optimism and purpose in life, healthy diet and omega-3 intake. A review of 19 studies suggests that certain brain-stimulating activities may help reduce AD risks. These include crossword puzzles, card games, computer use, arts or crafts, taking classes, group discussions, and listening to music.
Depending on the typed of exercise and its intensity, physical activity may lower AD risk by up to 65%. Underlying mechanisms may include reduction in blood vessel disease, better pulmonary function, increased cell survival, and anti-inflammatory effects.
Up to 30% of AD may be preventable by well-balanced, healthy lifestyle choices, including regular exercise, social engagement, and a healthy diet including recommended servings of fresh fruits and vegetables, whole grains, and lean proteins, and avoiding processed foods.
It still amazes me that prevention strategies only become essential when treatment strategies fail. Somehow taking a drug is preferable to adopting a healthy lifestyle?
In review, the Alzheimer’s Association predicts that by 2050, 16 million Americans will be suffering from a disease that is preventable in over 50% of all cases.
The Bottom Line:
AD, like diabetes, obesity, and almost all chronic degenerative diseases are preventable with a healthy diet, regular exercise, and staying engaged mentally. It’s a no brainer (pun intended). Finally, if you are not taking omega-3 fatty acids after reading this article you may be well on your way to developing AD.
Source: August 2, 2017 J. American Geriatric Society