Gaby
Dementia is usually associated with older age, but hundreds of thousands of people worldwide are diagnosed with early-onset dementia (YOD) each year. A comprehensive study by researchers at the University of Exeter (UK) and Maastricht University (Netherlands) sheds light on the factors behind those diagnoses.
Most prior research has focused on genetics as the main cause of early dementia. The authors of the new study, however, identified several risk factors for YOD that are largely tied to lifestyle and health conditions.
“This is the largest and most reliable study on early dementia ever conducted,” said British epidemiologist David Llewellyn. He added that the team’s findings show for the first time that certain factors can be modified to reduce the risk of this debilitating disease.
Dementia is a brain disorder marked by memory loss, attention deficits, impaired thinking, language difficulties, and trouble carrying out daily activities. It can also slowly erode a person’s personality and independence. More than 55 million people worldwide are living with dementia, and about 60 percent of them live in low- and middle-income countries. Around 10 million new cases are reported globally each year. Alzheimer’s disease is the most common form, accounting for roughly 60–70 percent of cases.
How the Study Was Conducted
The research team analyzed health data from 356,052 Britons under age 65. They found that higher risk of developing YOD was primarily associated with social isolation, hearing impairment, stroke, diabetes, heart disease, and depression.
Vitamin D deficiency and elevated levels of C-reactive protein (a marker of inflammation produced by the liver), along with having two copies of the APOE ε4 allele (a genetic variant already linked to Alzheimer’s disease), also indicated increased risk of early dementia.
Researchers described the relationship between alcohol use and YOD as a “complex” factor, according to ScienceAlert. Alcohol abuse was linked to a higher risk, while moderate and frequent consumption correlated with a lower risk — which may reflect that people in that group tend to be generally healthier. Researchers note that people who abstain completely sometimes do so for medical reasons.
A higher level of education and lower physical frailty (measured by grip strength) were also associated with reduced YOD risk.
The Value of the Study’s Findings
“From previous studies on people who developed dementia at older ages, we already knew there are several modifiable risk factors,” said Dutch neuroepidemiologist Sebastian Keller.
He said that alongside physical factors, mental-health issues such as chronic stress, loneliness, and depression also play a significant role. While the results did not prove a direct causal link between those mental-health factors and dementia, they add important context to the broader risk picture.
As with many studies of this kind, better understanding the causes helps guide prevention strategies and could lead to more effective treatments.
Many of the identified factors are modifiable, which offers more hope to people seeking ways to reduce dementia risk rather than only managing symptoms. Ultimately, adopting a healthier lifestyle may help lower the chance of developing dementia.
“Early-onset dementia has a profound effect on people’s lives, since patients often still have jobs, children, and active social roles,” said neurobiologist Stevie Hendricks of Maastricht University.
“Genetics has often been seen as the main cause of YOD, but in many cases other risk factors are involved that researchers hadn’t recognized before,” he added. That is why this research is important.
The study’s findings were published in JAMA Neurology.
