Blood lipids, infection, and inflammatory markers in the Tsimane of Bolivia

Abstract

Objectives Little is known about blood cholesterol (blood-C) levels under conditions of infection and limited diet. This study examines blood-C and markers of infection and inflammation in the Tsimane of the Bolivian Amazon, indigenous forager farmers living in conditions that model preindustrial European populations by their short life expectancy, high load of infections and inflammation, and limited diets. Methods We use multivariate models to determine the relationships between lipid levels and markers of infection and inflammation. Adult Tsimane (N = 418, age 20–84) were characterized for blood lipids, cells, and inflammatory markers in relation to individual loads of parasites and village region. Results Most of the Tsimane (60%) carried at least one parasite species, averaging 1.3 species per person. Serum high-density lipoprotein cholesterol (HDL-C), total cholesterol (total-C), and low-density lipoprotein cholesterol (LDL-C) were below the U.S. norms and varied inversely with markers of infection and inflammation: C-reactive protein (CRP), interleukin-6 (IL-6), erythrocyte sedimentation rate (ESR), immunoglobulin (Ig) E and eosinophil count. Although no relationship of parasite load to blood-C was found, there was an association between anemia and parasite prevalence. Conclusions We conclude that the highly infected environment of the Tsimane is related to low levels of blood total-C, HDL-C, and LDL-C. This may suggest a potential reason why arterial disease is largely absent in the Tsimane.

Early-life disease exposure and associations with adult survival, cause of death, and reproductive success in preindustrial humans

“…Thus, early-life disease exposure is expected to be linked to adult mortality risk from these causes in particular (6). Support for this hypothesis comes from studies showing that exposure to high levels of earlylife cohort mortality or infection is associated with middle-age mortality from CVD (10,11); that exposure to infection is associated with chronically high levels of inflammation (12,13); and that high levels of inflammation are associated with CVD (14). This physiological mechanism is underpinned by the fact that natural selection should favor the expression of robust immune responses at young ages, even at the cost of lower later-life survival (15).…”

Implications of market integration for cardiovascular and metabolic health among an indigenous Amazonian Ecuadorian population

“…Second, major changes in MI among Shuar are relatively recent; thus, the cumulative duration of exposure to cardiovascular and metabolic risks is likely lower than many other populations experiencing lifestyle change. Further, parasitism by helminth may help maintain normal blood lipid and BP levels (Vasunilashorn et al 2010;Liebert et al 2011). Indeed, helminth infections appear endemic, even in the UV Cepon et al 2012).…”

Twentieth century surge of excess adult male mortality

“…Differences in HDL are one mechanism through which blood estrogens provide premenopausal women with relative protection from CVD (30)(31)(32). Because HDL is lower among those with past and current exposure to infections (33,34), the increasing male vulnerability might also arise from greater increases in total cholesterol relative to HDL with increased fat consumption and weight gain.…”