Adolescent behaviors, alcohol use linked to young-onset dementia
Recent data published in JAMA Internal Medicine isolated nine independent risk factors from late adolescence associated with young-onset dementia, including adolescent drug and alcohol use.
“We found nine independent risk factors for [young-onset dementia], and most of these risk factors were originating from childhood and adolescence and were potentially modifiable, resulting in excellent opportunities for prevention,” Peter Nordström, PhD, of Umeå University in Sweden, said in an interview.
Nordström and colleagues looked at data from 488,484 men (mean age, 18 years) who were enrolled in the Swedish Military Service Conscription Register from 1969 to 1979. Baseline cognitive and physical examinations were measured as part of the conscription.
A median follow-up of 37 years revealed 506 cases of young-onset dementia, or dementia diagnosed before the age of 54 years. Thirteen of those cases were associated with Parkinson’s disease and six with Lewy body dementia and were thus excluded from the analysis. In addition, 36 men displayed mild cognitive impairment at a median age of 54 years.
In the remaining 487 cases of young-onset dementia, baseline use of antipsychotic drugs (HR=2.75; 95% CI, 2.09-3.60) and drug intoxication (HR=1.54; 95% CI, 1.06-2.24) were among the nine risk factors, with alcohol intoxication (HR=4.82; 95% CI, 3.83-6.05) identified as the most significant risk factor. The researchers identified 15% of the dementia cases as alcohol dementia.
“Whether alcohol dementia is caused directly by the toxic effects of alcohol or is predominantly related to secondary thiamine deficiency resulting in Wernicke encephalopathy is not clear,” the researchers wrote. “Although, our data suggest that the effect of alcohol abuse on the overall risk of [young-onset dementia] in men is at the present severely underestimated.”
Nordström and researchers were also able to link young-onset dementia to stroke (HR=2.96; 95% CI, 2.02-4.35), depression (HR=1.89; 95% CI, 1.53-2.34) and even low height at conscription (HR=1.16 per 1-standard deviation decrease; 95% CI, 1.04-1.29).
A 20-fold increased risk for young-onset dementia was associated with men who had at least two of the nine criteria and who displayed the lowest tier of cognitive function (HR=20.38; 95% CI, 13.64-30.44).
The researchers noted that 26,105 men died during the follow-up period. These deaths were associated with alcohol intoxication (HR=5.95; 95% CI, 5.71-6.20) and young-onset dementia diagnosis (HR=3.54; 95% CI, 2.77-4.53).
“Given that an alcohol intoxication was an unexpectedly strong risk factor, it would be of interest to further study this risk factor, eg, with respect to amount needed to result in [young-onset dementia],” Nordström said.
Disclosure: The study was funded by grants from the Swedish Research Council and the Swedish Dementia Foundation.