Associations Between Demographic Factors and Fecal Calprotectin in the Indigenous Shuar of Ecuadorian Amazonia: a Window into Inflammatory Bowel Disease (IBD)

39 pages. Presented to the Department of General Science and the Robert D. Clark Honors College in partial fulfillment of the requirements for the degree of Bachelor of Science June 2018Previous research has shown that autoimmune disorders like inflammatory bowel disease (IBD) are on the rise in wealthy nations such as the United States. However, virtually no research on IBD or its precursors, has been conducted in less wealthy nations. The present study addresses this issue by looking at demographic trends in levels of fecal calprotectin (FC), a biomarker of intestinal inflammation closely related to IBD, in a sample (n=79; 37 males, 42 females) of Shuar forager-horticulturalists from Ecuadorian Amazonia. There was a significant negative relationship between FC and age (p=0.04) (as age increased, FC decreased), not a curvilinear relationship as would be seen with IBD (where FC is high in childhood and late adulthood, and low in the middle of life). T-test results provided no evidence of a sex difference in mean FC levels (t=-1.14, p=0.259), and F-test results provide no evidence of sex differences in FC variance (ratio=1.15, p=0.66). These results indicate that Shuar had lower levels of FC in older age, whereas with more industrialized nations there is a curvilinear age pattern with an increase of FC in old age (50+ years old). This suggests that FC levels in this setting are not driven by IBD, but instead by other factors, perhaps parasite burden. Further study in what these other factors are should be done to better understand how they shape IBD pathology in industrializing nations