There are many factors that determine whether or not you will experience severe cognitive decline. Dementia is a complex set of diseases not completely understood by physicians and scientists. Risk factors are variables that contribute to your likelihood of getting a disease. For example, smoking cigarettes is a well-known risk factor for lung cancer. If you quit smoking, you reduce your risk of developing this cancer. Because the human body is extremely complicated, there are lots of different risk factors that come from your genetics, your environment, and your behaviors.
While it may not be possible to reduce your risk to zero, by taking steps to improve and maintain your brain health, you can significantly lower your likelihood of developing dementia. Lowering your risk can either slow the progression of cognitive decline or help stave it off completely.
Lower Your High Blood Pressure
Your cardiovascular system is responsible for pumping blood (and with it, nutrients like oxygen and glucose) to all regions of your body. Your brain relies heavily on your cardiovascular system for the nutrients it needs to function. Despite making up only 2% of your body weight, your brain requires 20% of your daily consumption of oxygen and calories.(1) Because of this close relationship, when your cardiovascular health declines so does your brain health.
High blood pressure, also known as hypertension, damages and weakens the walls of your arteries and veins. These weakened blood vessels are less efficient at circulating blood and are more likely to narrow, rupture, or leak. As fewer nutrients are able to reach your brain because of the reduced blood supply, brain cells can begin to deteriorate and die.(2)
Therefore, it is important to reduce high blood pressure until it falls until a healthy range, between 120 over 80 and 140 over 90 mmHg. There are several ways to alleviate hypertension both lifestyle-related and pharmaceutical. It is important to consult your physician to decide what regime is best for your health. Regular aerobic exercise like walking, jogging, or swimming for at least 30 minutes a day, 5 to 7 days a week, helps to regulate blood pressure levels. Additionally, stress can be a significant contributor to hypertension. If possible, develop strategies to either avoid stress or to manage it appropriately.(3)
Avoid Excessively Loud Noises to Protect Your Hearing
Hearing loss has a strong link to dementia. Mild hearing loss doubles your risk of dementia, and severe hearing loss increases your risk of dementia by 5 times.(4) As you age, pay attention to whether your hearing is worse than it used to be. Around one third of people over the age of 65 have hearing problems.(5) Hearing loss can be caused by age, repeated exposure to loud noises (e.g. loud, sustained music at full volume), blockages in the ear (e.g. a buildup of ear wax), injury, or a combination of these factors.
When your hearing starts to decline, your brain has to work harder to interpret the muffled sounds. By diverting more energy to listening, your brain spends less energy storing information into memory. People with hearing loss may also start to avoid social interactions due to the frustrations that come with the extra effort needed to have a conversation.(4)
Hearing aids can reduce the risk of dementia associated with hearing loss.(6) However, they are only helpful once your hearing has started to go. In the meantime, it is vital to protect your hearing. Follow manufacturer advice when it comes to Q-tips: don’t put them in your ear. Rather than help clean out ear wax, cotton swabs often push it further into the ear. Their use can lead to tears in the eardrum as well as excessive ear wax buildup which can cause hearing loss.(7) Additionally, avoid sustained exposure to loud noises, such as standing next to a speaker at a concert or listening to music full-blast with headphones. This cannot be emphasized enough. About half of impaired hearing cases in America are due to damage from exposure to loud noise. (8)
There are many reasons to quit smoking, and here’s one more: smoking increases your risk for dementia. A report from the World Health Organization estimates that smokers are 45% more likely to develop dementia compared to those who don’t smoke.(9)
Smoking negatively impacts your cardiovascular system. Consistent smoking narrows blood vessels in the heart and brain that increase your chances of strokes. Additionally, the toxins in cigarettes have been linked with harmful inflammation of brain cells.(9) Both of these factors contribute to cognitive decline.
It is never too late to quit. The sooner you stop smoking, the lower your risk for developing dementia. In fact, quitting smoking may even lower your risk of dementia down to the level of nonsmokers.(10) For both your loved ones’ health and your own, it is important to emphasize quitting smoking. Secondhand smoke increases the likelihood of developing dementia. Even if you have never smoked, living with a smoker increases your risk of cognitive decline by as much as 29%.(11)
Eat a Mediterranean Diet
Food can be a form of medicine. It gives us the energy and minerals we need to do our best throughout the day. The Mediterranean Diet has received a lot of attention from the medical community due to its positive impact on brain health. One study concluded that older adults who followed the Mediterranean diet had a 30-35% lower risk of memory impairment.(12)
The Mediterranean diet is mostly plant-based, with a focus on limiting saturated fat. This diet suggests a high intake of fruits, vegetables, legumes, whole grains, fish, and unsaturated fatty acids such as olive oil and avocado. It also encourages a moderate intake of dairy, wine, and poultry, with a low intake of red meats and sweets.
Due to its high levels of antioxidants and anti-inflammatory compounds, this diet fights against the harmful oxidative processes that occur within the aging brain. Oxidative damage is common in the brains of Alzheimer’s patients. The main components of the Mediterranean diet (fruits, vegetables, wine, olive oil) provide high levels of antioxidants that slow and even prevent this damage.(13)
Treat Your Depression
Depression and dementia have an interesting relationship. The two disorders have several symptoms that overlap: social withdrawal, apathy, loss of interest in previously enjoyed activities, impaired thinking, and problems with concentration.
A history of depression doubles the risk of dementia.(14) In addition to a history of dementia, the age of onset of depression influences dementia risk. Depression in midlife increases the risk of dementia by 19%, and depression in late life increases the risk by 72%.(15) People with depression who later developed Alzheimer’s disease were more likely to have motivational symptoms of depression than mood symptoms.(14) Motivational symptoms refer to loss of interest in hobbies, impaired concentration, and lack of energy.
Therefore, seek treatment for depression. Continued long-term use of antidepressant treatment reduces the risk of dementia by 17%.(16) One study found that long-term use of the antidepressant class SSRIs delayed the onset of dementia by three years, providing precious years of cognitive health.(17) Furthermore, depressive symptoms tend to worsen in the decade prior to a dementia diagnosis.(18) This means that it’s important to monitor both your cognitive health and your mental health over time.
- Raichle,M.E.,&Gusnard,D.A.(2002).Appraising the brain's energy budget. Proceedings of the National Academy of Sciences, 99(16),10237-10239.
- High blood pressure dangers: Hypertension’s effects on your body (2016,November23). MayoClinic.Retrieved from https://www.mayoclinic.org/diseases-conditions/high-blood-pressure/in-depth/high-blood-pressure/art-20045868
- High blood pressure (n.d.). National Heart, Lung, and Blood Institute.Retrieved from https://www.nhlbi.nih.gov/health-topics/high-blood-pressure#Treatment
- Lin, F. R., Metter, E. J., O’brien, R. J., Resnick, S. M., Zonderman, A. B., & Ferrucci, L. (2011). Hearing loss and incident dementia. Archives of neurology, 68 (2), 214-220.
- World Health Organization. (2012). WHO global estimates on prevalence of hearing loss. Geneva: World Health Organization.
- Amieva, H., Ouvrard, C., Giulioli, C., Meillon, C., Rullier, L., & Dartigues, J. F. (2015). Self-reported hearing loss, hearing aids, and cognitive decline in elderly adults: A 25-year study. Journal of the American Geriatrics Society, 63 (10), 2099-2104.
- Kumar, S. U. R. E. S. H., & Ahmed, S. H. A. M. I. M. (2008). Use of cotton buds and its complications. Journal of Surgery Pakistan (International), 13(3), 137-8.
- Daniel, E. (2007). Noise and hearing loss: a review. Journal of School Health, 77(5), 225-231.
- Tobacco & Dementia. (2014, June). World Health Organization. Retrieved from http://apps.who.int/iris/bitstream/handle/10665/128041/WHO_NMH_PND_CIC_TKS_14.1_eng.pdf;jsessionid=1C2EFFD092FAF5B4A84665CDB4BA65F0?sequence=1
- Smoking and dementia. (n.d.). Alzheimer’s Society. Retrieved from https://www.alzheimers.org.uk/about-dementia/risk-factors-and-prevention/smoking-and-dementia
- Secondhand Smoke Increases Dementia Risk. (2014, November 12). Fisher Center for Alzheimer’s Research Foundation. Retrieved from https://www.alzinfo.org/articles/secondhand-smoke-increases-dementia-risk/
- Alzheimer’s Association International Conference (AAIC 2017). (2017, June 17). Alzheimer’s Society. Retrieved from https://www.alzheimers.org.uk/news/2018-05-03/alzheimers-association-international-conference-aaic-2017
- Dai, J., Jones, D. P., Goldberg, J., Ziegler, T. R., Bostick, R. M., Wilson, P. W., … & Vaccarino, V. (2008). Association between adherence to the Mediterranean diet and oxidative stress–. The American journal of clinical nutrition, 88 (5), 1364-1370.
- Jorm, A. F. (2001). History of depression as a risk factor for dementia: an updated review. Australian & New Zealand Journal of Psychiatry, 35( 6), 776-781.
- Barnes, D. E., Yaffe, K., Byers, A. L., McCormick, M., Schaefer, C., & Whitmer, R. A. (2012). Midlife vs late-life depressive symptoms and risk of dementia: differential effects for Alzheimer disease and vascular dementia. Archives of general psychiatry, 69 (5), 493-498.
- Kessing, L. V., Forman, J. L., & Andersen, P. K. (2011). Do continued antidepressants protect against dementia in patients with severe depressive disorder?. International clinical psychopharmacology, 26 (6), 316-322.
- Bartels, C., Wagner, M., Wolfsgruber, S., Ehrenreich, H., Schneider, A., & Alzheimer’s Disease Neuroimaging Initiative. (2017). Impact of SSRI therapy on risk of conversion from mild cognitive impairment to Alzheimer’s dementia in individuals with previous depression. American Journal of Psychiatry, 175 (3), 232-241.
- Kaup, A. R., Byers, A. L., Falvey, C., Simonsick, E. M., Satterfield, S., Ayonayon, H. N., … & Yaffe, K. (2016). Trajectories of depressive symptoms in older adults and risk of dementia. JAMA psychiatry, 73(5), 525-531.