While dementia is more prevalent among older individuals, a substantial number are diagnosed with young-onset dementia (YOD) annually, and a comprehensive new study provides significant insights into its underlying causes.
Previous research predominantly focused on hereditary genetics, but this study identifies 15 distinct lifestyle and health factors linked to the risk of YOD.
“This marks the largest and most robust study of its kind,” says epidemiologist David Llewellyn from the University of Exeter in the UK. “Excitingly, it suggests that we might take measures to mitigate the risk of this debilitating condition by addressing various factors.”
Examining data from 356,052 individuals under 65 in the UK, the study associates low socioeconomic status, social isolation, hearing impairment, stroke, diabetes, heart disease, and depression with a heightened YOD risk. Vitamin D deficiency, elevated C-reactive protein levels (indicating inflammation), and having two ApoE4 ε4 gene variants (linked to Alzheimer’s disease) are also correlated with an increased risk.
The relationship between alcohol and YOD is described as “complex.” While alcohol abuse raises the risk, moderate to heavy drinking is associated with reduced risk, possibly because this group tends to be generally healthier. Higher formal education levels and lower physical frailty, measured through greater handgrip strength, are linked to a lower YOD risk, filling gaps in knowledge about YOD.
“We already knew from research on people who develop dementia at an older age that there are a series of modifiable risk factors,” says neuroepidemiologist Sebastian Köhler from Maastricht University in the Netherlands. “In addition to physical factors, mental health also plays an important role, including avoiding chronic stress, loneliness, and depression.”
While these results don’t confirm causation, they contribute to a more detailed understanding. In research of this nature, understanding the causes can lead to improved treatments and preventive measures. Many of these factors are modifiable, offering hope for those striving to find ways to prevent dementia rather than merely manage it. Ultimately, living healthier lives may reduce the risk of dementia.
“Young-onset dementia has a very serious impact because the affected individuals usually still have a job, children, and a busy life,” says neuroscientist Stevie Hendriks from Maastricht University. “The cause is often assumed to be genetic, but for many people, we don’t know exactly what the cause is. This is why we also wanted to investigate other risk factors in this study.
The research has been published in JAMA Neurology.
