16 October 2017:
The prevalence of Alzheimer's disease (AD) is constantly increasing to very alarming figures, and this already has a huge impact on society in terms of needed medical and nursing services as well as the associated financial burden. Herein, I bring a very condensed bullet-type summary published in Medscape by the author of a paper, just published in the Journal of the American Geriatric Society . First, the major risk factors, which are not modifiable, are age and female gender, and the presence of the apolipoprotein E ε4 allele. Still many risk factors may be modified and thus should be considered as worthy targets in the prevention of AD. These include optimal management of 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 lifestyle, and diet. These potentially modifiable risk factors, when combined, account for more than 50% of AD risk, based on observational studies. To note, many of these risk factors do not appear to affect amyloid or tau proteins.
Other modifiable factors appearing to protect against AD include cognitive reserve and mental activity, educational attainment and lifelong learning, cognitive leisure activities, social engagement, mindfulness and wellness activities, optimism and purpose in life, healthy diet, and omega-3 intake. Certain brain-stimulating activities may help reduce AD risks: crossword puzzles, card games, computer use, arts or crafts, taking classes, group discussions, and listening to music were mentioned in this context. Physical activity and exercise deserve special attention: depending on the type 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. Current data point at the fact that 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.
As well known, there is a clear need to better understand the pathophysiology and complex mechanisms which lead to the development of AD. For example, clear explanations are lacking regarding why some people and not others develop AD as they age. Unfortunately, and despite immense R&D efforts by the pharmacological industry, only few FDA-approved medications are available so far for memory and behavioral AD symptoms. This means that prevention strategies are essential, and should be employed as early as possible. Treating the relevant metabolic disorders and maintaining healthy lifestyle, including increased physical activity, adhering to the recommended diet, social engagement, and mentally challenging activities may be effective in reducing the risk of AD or slowing the pace of disease progression.
Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
Galvin JE. Prevention of Alzheimer's disease: lessons learned and applied. J Am Geriatr Soc 2017 Aug 2. Epub ahead of print