Dementia is a general term for a decline in mental ability that affects your everyday functioning. Common symptoms include:

  • memory loss
  • difficulty thinking
  • difficulty communicating
  • difficulty with coordination and motor functions
  • general confusion and disorientation

Several factors can affect your risk for developing dementia. You can change some of these factors, such as smoking, but not others, such as genetics.

It’s important to understand that a risk factor isn’t a cause. For example, diabetes is a risk factor for both Alzheimer’s disease (AD) and vascular dementia, but that doesn’t mean it causes AD or vascular dementia. Not all people with diabetes develop dementia.

Risk factors associated with dementia include the following:


Atherosclerosis is the thickening and hardening of artery walls due to plaque buildup. Plaque is made of cholesterol, fat, calcium, and other substances in the blood. This buildup can narrow your arteries and interfere with the flow of blood to your brain. This impairs the ability of your brain cells to function properly. This can ultimately lead to the death of these brain cells and their connections to other brain cells.


A high level of LDL cholesterol increases your risk of developing vascular dementia. This may be due to the association between atherosclerosis and high cholesterol.


This amino acid naturally circulates in your blood and is a building block of protein. A high level of homocysteine is a risk factor for a number of diseases, including:

  • Alzheimer’s disease
  • vascular dementia
  • cognitive impairment
  • stroke


Diabetes may be associated with an increased risk of developing both AD and vascular dementia. Diabetes is also a risk factor for atherosclerosis and stroke. Both of these can contribute to vascular dementia.

Psychological and experiential factors

Psychological and experiential factors may be a risk factor for dementia as well. For example, if you tend to socially isolate yourself or don’t regularly engage in cognitively stimulating activities, you may be at an increased risk of developing AD.

Mild cognitive impairment (MCI)

MCI can be thought of as a stage between normal forgetfulness and dementia. However, if you have MCI, it doesn’t mean you’ll develop Alzheimer’s. But most cases of Alzheimer’s start with MCI. Symptoms for MCI include:

  • memory loss greater than expected for your age
  • memory deficiency is great enough to be noticed and measured
  • continued independence because the deficiency isn’t enough to compromise your ability to care of yourself and conduct normal activities

Down syndrome

By middle age, most people with Down syndrome have the plaques and tangles of Alzheimer’s disease. Many also develop dementia.


The risk of developing Alzheimer’s disease, vascular dementia, and several other dementias increases as you age. In the United States, one in nine people over the age of 65 has Alzheimer’s, about five million people, according to the Alzheimer’s Association. One in three seniors dies with Alzheimer’s or another form of dementia.


Many forms of dementia have a genetic component and it often runs in families. In addition, certain mutations in specific genes have been identified as increasing the risk for developing dementia.


A study in the JAMA Neurology journal found that smoking may significantly increase your risk of mental decline and dementia. If you smoke, you have a higher risk of atherosclerosis and other types of vascular disease. These diseases may contribute to the increased risk of dementia.

Alcohol use

Drinking large amounts of alcohol also increases your risk of developing a type of dementia known as Korsakoff syndrome. Symptoms of Korsakoff syndrome include:

  • difficulty learning new information
  • short-term memory loss
  • long-term memory gaps

Many risk factors are involved in developing dementia, including medical conditions, lifestyle choices, genetics, and old age. If you have a high risk for developing dementia, see your doctor about how you can prevent it and any lifestyle changes that may help.