Alcohol abuse, coming from a lower socio-economic background, loneliness and a hearing impairment are among 15 factors found to significantly increase the risk of early-onset dementia, according to a “groundbreaking” study.
Almost 4 million people worldwide experience dementia symptoms under the age of 65, with 370,000 people newly diagnosed each year.
While previous research has found that lifestyle changes can reduce the risk of dementia among older people, the authors of the new study said this was the first finding to suggest that the risk of early-onset dementia could be reduced in the same way.
The study looked at 350,000 under-65s who were part of the UK Biobank study. Researchers from the universities of Exeter and Maastricht investigated what might influence a person’s susceptibility to early-onset dementia, including genetic, lifestyle and environmental factors.
They found 15 factors that significantly increased the risk, including lower formal education or lower socioeconomic status, health factors such as vitamin D deficiency, hearing impairment and depression, and lifestyle factors such as alcoholism and social isolation.
“Our study identified 15 lifestyle and health-related factors associated with the incidence of young-onset dementia,” the researchers said.
“… Although further investigation of these risk factors is needed to identify potential underlying mechanisms, addressing these modifiable factors may be effective in mitigating the risk of young-onset dementia and can be readily integrated into current dementia prevention initiatives.”
Dementia is one of the biggest diseases facing the UK health infrastructure, and a study last month suggested that 1.7 million people in the UK may have the condition by 2040. There are about 900,000 people in Britain living with dementiawhile more than 70,800 are living with early-onset dementia.
Sebastian Köhler, a professor of neuroepidemiology at Maastricht University and one of the lead authors of the research, said: “We already knew from research on people who develop dementia at an older age that there are a range of modifiable risk factors .
“In addition to physical factors, mental health also plays an important role, including avoiding chronic stress, loneliness and depression. The fact that this is also evident in young-onset dementia came as a surprise to me, and it may offer opportunities to reduce risk in this group as well.”
Dr Janice Ranson, a senior research fellow at the University of Exeter, said the research “breaks new ground in identifying that the risk of young-onset dementia can be reduced”.
She added: “We think this could usher in a new era in interventions to reduce new cases of this condition.”
Dr Leah Mursaleen, the head of clinical research at Alzheimer’s Research UK, who co-funded the study, said: “We are seeing a transformation in understanding of dementia risk and, potentially, how to reduce it at an individual and societal level.
“In recent years there has been a growing consensus that dementia is linked to 12 specific modifiable risk factors such as smoking, blood pressure and hearing loss. It is now believed that up to four out of 10 dementia cases worldwide are linked to these factors.
“This pioneering study sheds important and much-needed light on factors that may influence the risk of young-onset dementia. This begins to fill an important gap in our knowledge. It will be important to build on these findings in wider studies.”
The study was published in JAMA Neurology.