15 Factors Linked to Early-Onset Dementia

Researchers in Europe have identified 15 factors associated with risk in developing young-onset dementia. Many can be modified through lifestyle changes or medical treatment, which suggests that steps taken to improve overall health may also help lower the risk of developing dementia at a younger age.

Early-Onset Dementia

Dementia symptoms that appear before age 65 are called early-onset or young-onset dementia. Dementia is an an umbrella term referring to similar conditions of cognitive decline (Alzheimer's disease, frontotemporal dementia, vascular dementia, and so on). Currently, about 3.9 million people have early-onset dementia worldwide. 

Early-onset is a less common dementia, but because it strikes younger people during their working years, its impact tends to be profound, interrupting the trajectory of the patient’s life, reducing income, and shifting family members into caretaking roles.

Signs of early-onset dementia such as memory loss and changes in personality, behavior, language, judgment, or problem-solving can look like simply the effects of stress or depression. An accurate diagnosis requires a comprehensive evaluation, testing, and scans. 

Drivers of Early Dementia

The study analyzed data from more than 356,000 adults enrolled in the UK Biobank, none of whom had dementia when the study began. Participants were followed for an average of just over eight years, during which 485 developed young-onset dementia.

Researchers examined 39 possible risk factors spanning genetics, lifestyle, cardiovascular health, mental health, blood markers, and socioeconomic factors. After accounting other influences, 15 remained significantly associated with young-onset dementia.

Conditions Linked to Higher Risk

• Stroke
• Diabetes
• Heart disease
• Depression
• Hearing impairment
• Orthostatic hypotension (a condition in which blood pressure drops when a person stands up, leading to decreased blood flow to the brain)
• Vitamin D deficiency
• Elevated levels of C-reactive protein, a marker of inflammation
• Alcohol use disorder 
• Social isolation (seeing friends or family no more than once a month)

What Lowered Risk

• Higher levels of education
• Stronger handgrip strength (a measure of physical fitness and frailty)
• Higher socioeconomic status (which often enables better access to medical care, less stress, and a higher quality diet)

Alcohol Consumption

The effect of alcohol was more difficult to interpret. 

Those who reported moderate or heavy alcohol consumption seemed to show a lower risk of young-onset dementia compared to non-drinkers. Researchers caution that rather than suggesting alcohol consumption is protective, it may reflect that some who abstain from drinking do so due to known medical problems or medications that might already give them an increased risk of dementia. 

In contrast, alcohol use disorder was consistently linked to a higher risk.

Genetics

The study also confirmed the importance of genetics. Participants who carried two copies of the APOE ε4 gene variant had a significantly higher risk of developing young-onset dementia than those who carried none.

Interestingly, per this study, genetic factors account for only a small proportion of young-onset dementia cases. This makes these modifiable lifestyle choices especially important.

Conclusions

This was an observational study. It does not prove that any of these factors directly cause young-onset dementia. Even so, many of the identified factors overlap with known risks for dementia later in life and are key in long-term health and in causing other diseases.

It is possible that some risks such as depression or orthostatic hypotension could represent an early sign of dementia rather than a cause.

Addressing potentially modifiable factors like cardiovascular health, hearing loss, vitamin D deficiency, depression, social isolation, and alcohol use disorder, could be strategies to help reduce the risk of young-onset dementia. 

Additional research is needed to confirm the findings and better understand how these factors influence the development of the disease.