Year: 2026
Type: article
Study design: Observational Study
Abstract: INTRODUCTION: We studied dementia incidence and risk factors in Indigenous Tsimane and Moseten Amerindian populations in Amazonian Bolivia with largely subsistence lifestyles. METHODS: A median of 4.7 years after baseline dementia assessment, 730 participants (52% male; mean age 67.3 years) were re-visited at two follow-up phases to determine new cases among non-demented at baseline. Clinical evaluation was adapted to culture, language, and illiteracy. RESULTS: There were 22 incident dementia cases (7.40/1000 person years; 95% confidence interval = 4.87-11.24). Prevalence rates remained < 2%. Mortality among dementia cases at baseline was significantly greater versus cognitively normal participants. In exploratory analyses, apolipoprotein E ε4 genotype, thoracic aortic calcium, and plasma neurofilament light chain were associated with incident dementia; other risk factors, amyloid, and phosphorylated tau were non-significant. DISCUSSION: In these populations, dementia prevalence is strikingly low, reflecting modestly low incidence and shortened life expectancy after diagnosis. Next steps include delineating vascular contributions versus Alzheimer's disease pathology in dementia cases.
Source: Alzheimer s & Dementia
DOI: 10.1002/alz.71750
Authors: Margaret Gatz, Wendy J. Mack, Daniel Eid Rodriguez, Raul Quispe Gutierrez, Jesus Bani Cuata, Helena C. Chui, Ellen E. Walters, Daniel K. Cummings, Paul L. Hooper, Henrik Zetterberg, Caleb E. Finch, Benjamin C. Trumble, Jonathan Stieglitz, Michael D. Gurven, Randall C. Thompson, Gregory S. Thomas, The HORUS Team, Tsimane Health and Life History Project, Hillard S. Kaplan
Institutions: University of Southern California, Universidad Mayor de San Simón, Chapman University, University of New Mexico, University of Wisconsin–Madison, Sahlgrenska University Hospital, National Hospital for Neurology and Neurosurgery, UCL Queen Square Institute of Neurology, University College London, University of Gothenburg, Arizona State University, Toulouse School of Economics, Université Toulouse Capitole, University of California, Santa Barbara, University of Missouri–Kansas City, University of California, Irvine, MemorialCare Health System
Language: English
Subfield: Psychiatry and Mental health
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Estimated APC paid: $4,200
OpenAlex ID: W7213293544