Document Type
Article
Publication Date
8-22-2025
Abstract
Background
Greater deposits of epicardial adipose tissue are associated with atrial fibrillation and coronary disease, but have not been studied in subsistence populations.Methods
We performed CT imaging to measure coronary artery and thoracic aortic calcium (CAC, TAC), epicardial fat thickness (EFT), liver density, and left atrial (LA) anteroposterior diameter and, using a deep learning-enabled software program, epicardial and thoracic fat volume (EFV, TFV), in two remote Amerindian subsistence populations with minimal coronary artery calcification and virtually no atrial fibrillation. We compared 893 adult Tsimane (mean age 58.3±10.5 y, 51.6% male), 440 Moseten (55.9±10.4 y, 53.6% male) to 955 U.S. (56.8±10.8 y, 51.6% male) subjects.Results
Tsimane and Moseten had 43%-52% lower EFT, EFV, TFV, and 48-92% less CAC and TAC, respectively than the U.S. cohort. Mean liver measurements were 14-22% denser and LA diameters 10-14% larger (≈ 40% larger by volume). For EFV, Tsimane, Moseten, and U.S. cohorts averaged 54.2±25.6, 60.3±35.1, and 106±53.5 cc, respectively (p< 0.05 for all comparisons). EFV remained significantly smaller after adjustment for age, BMI, and other characteristics. For all CT metrics, the more acculturated Moseten measures were intermediate between Tsimane and the U.S. cohort.Conclusions
Tsimane mean EFV was the lowest of any population ever reported in the literature, achieving a new population standard. The low levels of EFV in the Tsimane and Moseten add to the body of evidence linking ectopic fat and atherosclerosis and further confirm (in the negative) the association, and likely causative role, of epicardial fat and atrial fibrillation.Recommended Citation
Thompson, R. C., Trumble, B. C., Cummings, D. K., Neunuebel, A. D., Hooper, P. L., Wann, S., Allam, A. H., Neunuebel, F., Gans, B. D., King, S. I., Seabright, E., Finch, C. E., Gatz, M., Buetow, K., Miyamoto, M. I., Lombardi, G. P., Sutherland, M. L., Sutherland, J. D., Ward, C., Lee, M. J., et al. (2025). Ectopic adipose tissue in subsistence populations with minimal coronary disease, large left atria, and very low rates of atrial fibrillation. American Journal of Preventive Cardiology, 23, 101271. https://doi.org/10.1016/j.ajpc.2025.101271 Ectopic adipose tissue in subsistence populations with minimal coronary disease, large left atria, and very low rates of atrial fibrillation. American Journal of Preventive Cardiology Volume 23, September 2025, 101271. https://doi.org/10.1016/j.ajpc.2025.101271
Appendix. Supplementary materials
Peer Reviewed
1
Copyright
The authors
Creative Commons License

This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License
Included in
Biological and Physical Anthropology Commons, Economic Theory Commons, Other Economics Commons
Comments
This article was originally published in American Journal of Preventive Cardiology, volume 23, in 2025. https://doi.org/10.1016/j.ajpc.2025.101271