AURORA, CO — Using the VA’s Million Veteran Program data, a new study has determined that a diabetes genetic risk score is associated with all-cause dementia and clinically diagnosed vascular dementia in veterans.
“Diabetes and dementia are diseases of high health care burden worldwide, and studies have shown that diabetes is associated with an increased relative risk of dementia,” wrote the authors from the VA Eastern Colorado Healthcare System and the University of Colorado Anschutz Medical Campus, both in Aurora. “We set out to examine whether type 2 diabetes-associated genetic variants were associated with dementia and whether they differed by race/ethnicity or clinical dementia diagnosis.” VAMCs from Boston, Salt Lake City, Philadelphia, Atlanta and San Diego also participated in the study.
For the report in Diabetes Care, The study team evaluated associations of two Type 2 diabetes genetic risk scores (GRS and GRS-nonAPOE: a score without rs429358, a variant associated with Alzheimer’s disease [AD]) with three classifications of clinical dementia diagnoses in the Million Veteran Program (MVP). Those were dementia, vascular dementia (VaD) and AD. The analysis was stratified by European (EUR), African (AFR) and Hispanic (HIS) races/ethnicities.1
“In EUR, we found associations of the GRS with all-cause dementia (odds ratio [OR] 1.06, P = 1.60e-07) and clinically diagnosed VaD (OR 1.12, P = 5.2e-05) but not with clinically diagnosed AD (OR 1.02, P = 0.43),” the researchers reported. “The GRS was not associated with any dementia outcome in AFR or HIS. When testing with GRS-nonAPOE, we found that effect size estimates in EUR increased and P values decreased for all-cause dementia (OR 1.08, P = 2.6e−12), for VaD (OR 1.14, P = 7.2e−07), and for AD (OR 1.06, P = 0.018).”
For those of African race, the association of GRS-nonAPOE and clinically diagnosed VaD (OR 1.15, P = 0.016) was found to be statistically significant. There were no significant findings for those of Hispanic background.
“We found evidence suggesting shared genetic pathogenesis of diabetes with all-cause dementia and clinically diagnosed VaD”, the researchers advised.
- Litkowski EM, Logue MW, Zhang R, Charest BR, et. al. VA Million Veteran Program (MVP). A Diabetes Genetic Risk Score Is Associated With All-Cause Dementia and Clinically Diagnosed Vascular Dementia in the Million Veteran Program. Diabetes Care. 2022 Aug 30:dc220105. doi: 10.2337/dc22-0105. Epub ahead of print. PMID: 36041056.
