Inflammaging is minimal among forager-horticulturalists in the Bolivian Amazon

An increase in chronic systemic inflammation in later life, termed
inflammaging, is implicated in health risk. However, it is unclear whether
inflammaging develops in all human populations, or if it is the product of
modern environmental mismatch. We assessed inflammaging in Tsimane
forager-horticulturalists of the Bolivian Amazon, using serum cytokines in
a primarily cross-sectional sample (1,134 samples from n = 714, ages
39-94, 51.3% female). IL-6 was positively associated with age (β = 0.013,
p < 0.01). However, other pro-inflammatory markers, including IL-1β
and TNF-α, did not increase with age (β = -0.005 and β = -0.001,
respectively). We then compared the Moseten, a neighboring population that
has experienced greater market integration (423 samples from n = 380, ages
39-85, 48.2% female). The Moseten also showed a positive age association
for IL-6 that attenuated at later ages (age β = 0.025, p < 0.01;
age2 β = -0.001, p < 0.05). Further, IL-1β and TNF-α were both
positively associated with age (β = 0.021, p < 0.05, and β = 0.011,
p < 0.01, respectively). Our results demonstrate minimal
inflammaging in the Tsimane, highlighting variation across populations in
this age-related process. They also suggest inflammaging is exacerbated by
lifestyle shifts.