BOSTON — Because of overlapping symptom profiles observed in cognitive disorders, psychiatric disorders, and environmental exposures such as head injury, clinicians can find it difficult to detect early signs of Alzheimer’s disease and related dementias (ADRD).
A recent study in Alzheimer’s Research & Therapy pointed out that post-traumatic stress disorder (PTSD) and traumatic brain injury (TBI) are associated with self-reported problems with cognition and also appear to play a role in risk for ADRD.1
“The interplay between PTSD, head injury, subjective (self-reported) cognitive concerns and genetic risk for ADRD is also not well understood, particularly in diverse ancestry groups,” wrote the VA Boston Healthcare System-led researchers. The Center of Excellence for Stress and Mental Health at the VA San Diego Healthcare System also participated in the study.
The study team used data from the VA’s Million Veteran Program (MVP) to examine the relationship between dementia risk factors (APOE ε4, PTSD, TBI) and subjective cognitive concerns (SCC) measured in 140,921 individuals of European, 15,788 of African and 8,064 of Hispanic ancestry (EA, AA and HA, respectively). The researchers then used data from the VA electronic medical record to perform a retrospective survival analysis evaluating PTSD, TBI, APOE ε4 and SCC and their associations with risk of conversion to ADRD in veterans aged 65 and older.
Results showed that PTSD symptoms (B = 0.50-0.52, p < 1E-250) and probable TBI (B = 0.05-0.19, p = 1.51E-07-0.002) were positively associated with SCC across all three ancestry groups. “APOE ε4 was associated with greater SCC in EA Veterans aged 65 and older (B = 0.037, p = 1.88E-12),” the authors advised. “Results of Cox models indicated that PTSD symptoms (hazard ratio [HR] = 1.13-1.21), APOE ε4 (HR = 1.73-2.05) and SCC (HR = 1.18-1.37) were positively associated with risk for ADRD across all three ancestry groups. In the EA group, probable TBI also contributed to increased risk of ADRD (HR = 1.18).”
The researchers said their findings “underscore the value of SCC as an indicator of ADRD risk in veterans 65 and older when considered in conjunction with other influential genetic, clinical, and demographic risk factors.”
“We undertook this study to clarify the relationships between SCC and psychiatric and genetic risk factors for ADRD to advance our understanding of how these associations vary across age and race/ethnicity,” the researchers wrote.
They had hypothesized that increased SCC would be associated with higher risk for ADRD onset after accounting for genetic risk (APOE ε4), PTSD, TBI, demographic and lifestyle covariates.
- Neale ZE, Fonda JR, Miller MW, Wolf EJ, Zhang R, Sherva R, Harrington KM, Merritt V, Panizzon MS, Hauger RL, Gaziano JM; VA Million Veteran Program; Logue MW. Subjective cognitive concerns, APOE ε4, PTSD symptoms, and risk for dementia among older veterans. Alzheimers Res Ther. 2024 Jun 29;16(1):143. doi: 10.1186/s13195-024-01512-w. PMID: 38951900; PMCID: PMC11218206.