High Inflammation, Low Heart Disease in Amazonian Tribe
New research finds inflammation, infection not always predictive of cardiovascular disease
18 aug 2009-- As shown by an Amazonian population with high rates of inflammation and infection but low adiposity and robust fitness, inflammation is not always a risk factor for arterial degeneration and cardiovascular disease, according to research published Aug. 11 in PLoS One.
Michael Gurven, Ph.D., of the University of California in Santa Barbara, and colleagues conducted a study of 258 Tsimane adults, an Amazonian forager-horticulturalist population. Several predictors of heart disease were measured, including hypertension, obesity, diet, and smoking habits.
Using markers including C-reactive protein and white blood cells, the researchers found high levels of inflammation and infection among the Tsimane. However, rates of obesity, smoking, and blood lipids (total cholesterol and low density lipoprotein) were lower among the Tsimane population compared with the U.S. population. The investigators found peripheral artery disease was absent among all the Tsimane adults included in the study. In addition, the overall rate of hypertension among the adult population was 3.5 percent, and although this increased with age it peaked at 23.5 percent, a rate much lower than that in the United States and other developed countries.
"Our study provides evidence that chronic low-grade inflammation in the absence of several other risk factors is not a determinant of cardiovascular disease in a subsistence population. Inflammation and infection may not accelerate arterial degeneration in the context of restricted caloric intake, parasitism, and daily physical activity that maintains low body mass index," the authors conclude.