These 15 lifestyle and health factors may increase your risk of early dementia, new study finds

Loneliness, vitamin D deficiency, low socioeconomic status, and alcohol abuse disorder are just a few of the health and lifestyle factors associated with an increased risk of early- or young-onset dementia, according to a groundbreaking new study.

The findings, published in JAMA Neurology, challenge previous notions about the causes of the condition and lay the groundwork for new prevention strategies, the study authors wrote.

Researchers at University of Exeter and Maastricht University followed more than 350,000 participants under the age of 65 from across the United Kingdom in the UK Biobank (a large biomedical database) to understand the risks of early dementia.

Risk factors for young-onset dementia

In the new study, researchers investigated the association between 39 potential risk factors and the incidence of young-onset dementia among 356,052 participants to understand how health, social and environmental influences play a role.

Of these risk factors, researchers identified 15 that were significantly associated with a higher risk of young-onset dementia:

Social isolation

Lower formal education

Lower socioeconomic status

Carrying two copies of the APOE gene

Vitamin D deficiency

Hearing impairment

Alcohol use disorder

No alcohol use (abstinence)

Depression

High C-reactive protein levels

Lower handgrip strength (physical frailty)

Orthostatic hypotension (a form of low blood pressure)

Stroke

Diabetes

Heart disease

Most of these overlap with the known risk factors for and behaviors that reduce risk of late-onset dementia, the study authors wrote.

“We were surprised by just how many risk factors for dementia in elderly people were also important in people who were middle-aged,” David Llewellyn, Ph.D., study co-author and professor of clinical epidemiology and digital health at the University of Exeter, tells TODAY.com.

The study also identified several risk factors for young-onset dementia that had not been reported or studied before, the researchers wrote, including social isolation, vitamin D deficiency, orthostatic hypotension, and high C-reactive protein (CRP) levels.

Researchers found that participants who saw friends or family once a month or less had a higher association with young-onset dementia, suggesting a link between isolation and cognitive reserve.

Vitamin D is important for building bones, immune function and brain health — and getting enough of it may reduce the risk of young-onset dementia. "It has been suggested that vitamin D acts as a neurosteroid that protects against neurodegenerative processes," the study authors wrote.

The 15 risk factors varied in importance, Llewellyn notes, but more research is needed to confirm how they rank. “There may be additional risk factors that we still need to identify,” he adds.

Additionally, the relationship between dementia and certain risk factors, such as alcohol use, is complex. For example, both "no alcohol" and "alcohol use disorder" made the list of 15 key factors.

Researchers found people with a diagnosis of alcohol use disorder had a higher risk of young-onset dementia. However, moderate to heavy alcohol consumption was associated with a lower incidence compared to abstinence. "This may be due to the 'healthy drinker effect,' in which people who drink are healthier, while abstainers are more likely to not consume alcohol because of poor health or use of medication," the study authors wrote.

Ultimately, the findings suggest that many risk factors for young-onset dementia are controllable and addressing these through lifestyle changes may lower a person's risk.

"There’s good evidence that staying physically, mentally and socially active may help to protect the brain as we age," says Llewellyn. "In addition, try to avoid or at least carefully manage any health conditions that you have," he adds, especially high blood pressure, diabetes and depression.

"We can be hopeful that a wide range of modifiable risk factors appear important, thus we can be hopeful that dementia can be delayed or even prevented," says Llewellyn.

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