About half of American Indians between 70 and 95 years old are affected by some cognitive impairment. Of them, 35% have mild cognitive impairment and approximately 10% had dementia, according to a report published Wednesday in Alzheimer’s & Dementia.
Plasma pTau, glial fibrillary acidic protein (GFAP), and neurofilament light chain (NfL) were higher among those with cognitive impairment, but not amyloid beta (Aβ), the report found.
The study is the first large, prospective, population-based study to estimate the prevalence of vascular and Alzheimer’s dementias in American Indians. Other reports have reported numbers on this population. Data came from the Strong Heart Study, which includes American Indian tribes conducted over 30 years and three geographic regions across the country. Participants had cognitive tests, neurological exams and brain imaging over two visits about seven years apart.
The prevalence of the disease in American Indians and other indigenous peoples has been underrepresented in research. Disparities in socioeconomics, as well as historical and sociological factors increase the risk for the disease in this population. American Indians, specifically, have a high prevalence of comorbidities including diabetes, hypertension and depression. These are exacerbated by poor access to socioeconomic resources.
Traumatic injury was more prevalent in American Indians than in other populations, and common among those in the “other/not MCI” cognitive impairment category, according to data.
The report also showed that scores for common screening tools was low compared to other populations, the authors reported.
Vascular and neurodegenerative injuries were approximately equally responsible for cognitive impairment, the data showed. This indicates that reducing cardiovascular disease is needed for primary prevention of Alzheimer’s disease and vascular dementias.
Traumatic head injury was a significant contributor for dementia and Alzheimer’s disease among “other” impairments, perhaps representing acute cognitive changes, authors of the study reported. These findings aligned with prior research that found higher prevalence of biomarkers for neuronal remodeling in this population.
