Heavy drinking as a teenager is the single biggest risk factor for developing dementia unusually early, according to new research.
A study of almost 500,000 Swedish men identified “alcohol intoxication” as a late adolescent as the most serious of nine separate risk factors for young onset dementia (YOD) – that is, dementia before reaching 65.
Researchers led by Prof Peter Nordstrom, of Sweden’s Umea University, examined the records of 488,484 men conscripted into military service in the country at an average age of 18 between 1969 and 1979, 487 of whom were later diagnosed with YOD at an average age of 54.
About 800,000 people in the UK have dementia, of whom more than 17,000 developed it before they turned 65, according to the Alzheimer’s Society. Two-thirds of sufferers are women and a third are men.
Other “late adolescent risk factors” identified by the researchers included stroke, use of amtopsychotic drugs, depression, father’s dementia, drugs intoxication other than alcohol, low cognitive function at conscription, low height at conscription and high systolic blood pressure at conscription. Together the nine factors accounted for 68% of the 487 YOD cases found at follow-up.
Men with at least two of the nine risk factors, and who fell in the lowest third of the study participants for overall cognitive function, had a 20-fold increased risk of developing YOD, the researchers found.
“We are a long way off knowing exactly why some people develop dementia and others don’t. However, what this study shows once again is that many of the things we are beginning to identify as risk factors are controllable”, said Jess Smith, a research officer at the Alzheimer’s Society. “Kicking excessive teenage drinking or drug habits into touch and treating conditions such as depression early could be key to reducing your risk of dementia in later life.”
