Head trauma, PTSD linked to Alzheimer's disease, related dementias

Traumatic brain injury, PTSD and the apolipoprotein E4 gene showed strong associations with Alzheimer’s disease and related dementias, researchers reported in Alzheimer’s & Dementia.

PTSD and TBI are independently associated with risk for AD. However, the simultaneous impact has never been researched, Mark W. Logue, PhD, a statistician in the National Center for PTSD at the VA Boston Healthcare System, and colleagues wrote.

Logue and colleagues evaluated the impact of APOE4, PTSD and TBI on AD and related dementias (ADRD) prevalence in veteran cohorts of European and African ancestries.

In the European cohort there were 11,112 cases of ADRD and 170,361 controls; in the African cohort there were 1,443 cases of ADRD and 16,191 controls.

Additive-scale interactions were calculated through the relative excess risk due to interaction statistic.

The researchers reported an increase in risk due to PTSD and TBI in veterans of European ancestry who inherited the APOE4 gene. In veterans of African ancestry, TBI showed an increased risk, but not PTSD.

“These additive interactions indicate that ADRD prevalence associated with PTSD and TBI increased with the number of inherited APOE4 alleles,” Logue and colleagues wrote. “PTSD and TBI history will be an important part of interpreting the results of ADRD genetic testing and doing accurate ADRD risk assessment.”

Reference:

Head trauma, PTSD may increase genetic variant’s impact on Alzheimer’s risk. https://www.research.va.gov/currents/1222-Head-trauma-PTSD-may-increase-genetic-variants-impact-on-Alzheimers-risk.cfm. Published Dec. 22, 2022. Accessed Dec. 23, 2022.