Risk Factors for Dementia
Dementia—the gradual loss of mental function, including memory—is devastating. It’s heartbreaking to see someone you love lose the ability to live independently, and it’s terrifying to think that you may someday develop dementia.
At present, there’s no assured way to prevent dementia. However, understanding the risk factors for Alzheimer’s disease and dementia may help you modify your risk. Learn more about dementia risk factors, including age, smoking, alcohol use and family history.
The biggest risk factor for all types of dementia, including Alzheimer’s disease, vascular dementia, and Lewy body dementia, is increasing age. The older a person is, the greater their odds of developing dementia. It is statistically very unlikely for a 25-year-old to develop dementia; it is quite common to see 85-year olds with dementia.
However, dementia is not an inevitable part of the aging process. All changes in mental functioning and behavior should be reported to a physician. In some cases, mental changes are due to a treatable physical illness.
Smoking and a history of tobacco use have long been associated with an increased risk of dementia. Smoking is known to increase a person’s blood pressure and damage the inside lining of blood vessels over time, leading to a condition called atherosclerosis, or “hardening of the arteries.” High blood pressure and atherosclerosis decrease blood flow to the brain and may cause strokes. Vascular dementia is caused by a series of strokes over a long period of time.
However, a 2019 study that followed more than 500 adults over many years did not find a link between smoking and dementia.
Heavy alcohol use may increase the risk of dementia, particularly if the use continues over a period of years. According to the Alzheimer’s society, “excessive alcohol consumption over a lengthy time period can lead to brain damage and may increase your risk of developing dementia.”
A few studies have suggested that moderate alcohol consumption may decrease the risk of dementia. However, medical experts do not recommend that non-drinkers begin consuming alcohol in an effort to stave off dementia, as alcohol negatively affects many systems of the body.
Many people with Down syndrome develop dementia as they age. According to the National Institute on Aging, by age 40, almost all people with Down syndrome have protein “clumps” in their brains; these clumps are associated with dementia and Alzheimer’s disease. Symptoms often appear when individuals are in their 50s or 60s. Approximately 50% of people with Down syndrome will develop dementia due to Alzheimer’s disease as they age.
Type 1 and type 2 diabetes increase your risk of developing Alzheimer’s disease and vascular dementia. High blood sugar levels can damage brain cells over time. Diabetes also increases the risk of cardiovascular disease, including narrowed arteries and high blood pressure, which can cause vascular dementia.
Keeping your blood sugar levels within recommended limits may decrease your risk of dementia. Take your medications as prescribed, eat healthy, and exercise regularly.
6Family history of dementia
If others in your family have developed dementia, you may be at increased risk. Researchers working to understand dementia have discovered a few genes that seem to increase risk. A mutation of the apolipoprotein E (APOE) gene increases the risk of dementia and is associated with an earlier age of disease onset. However, having this mutation does not definitively mean that you will develop dementia. Inherited mutations also play a role in some cases of frontotemporal dementia.
Researchers are studying the interaction between genes and the environment to better understand the link between genetic mutations and dementia.
Hearing loss is associated with dementia, which may not be surprising, given that both conditions are more common with advanced age. However, researchers are currently studying whether hearing loss may cause or exacerbate dementia. One theory is that hearing difficulties strain the brain; it takes more effort and concentration to follow conversations, leaving less brain power for other cognitive efforts.
Another theory posits that the social isolation caused by hearing loss may accelerate cognitive decline. Additional research is needed to better understand the link between hearing loss and dementia.
8High blood pressure
The brain requires a steady supply of oxygen to function optimally. Anything that interferes with oxygen delivery to the brain has the potential to harm thinking and cognition.
Cardiovascular disease, high blood pressure and hardening of the arteries can decrease the flow of blood and oxygen to the brain. Common risk factors for vascular dementia (the second most common cause of dementia after Alzheimer’s disease in people over age 65) are heart disease, high blood pressure, hardening of the arteries, and smoking.
Keeping your blood pressure under control may decrease your risk of dementia.