Culture and colorectal cancer screening on three American Indian reservations

Colorectal cancer (CRC) rates among many American Indian populations are high. Screening by fecal occult blood test (FOBT) and endoscopy is effective for reducing CRC mortality, but little research has examined the extent of such screening in reservation populations. Further, nothing is known of how American Indians' cultural characteristics may be related to screening receipt.

We examined data from participants recruited from 2 Northern Plains and 1 Southwest reservation for the Education and Research Toward Health (EARTH) study. All participants aged > or = 51 years were eligible for inclusion.

After calculating screening rates, we examined bivariate relationships between screening and participant characteristics, including measures of cultural characteristics including ethnic identity and use of traditional healing practices. We applied multivariate regression to relate these cultural variables to odds of lifetime screening by FOBT or endoscopy.

Of 751 American Indians sampled, 35% reported lifetime CRC screening by at least one modality. Multivariate analyses did not reveal significant relationships or trends relating FOBT to respondents' cultural characteristics. By contrast, odds of endoscopy were significantly lower among persons who spoke a tribal language at home (OR .6, 95% C.I. .4-.9), and trend analysis revealed an inverse relationship between endoscopy and number of identity measures endorsed (Ptrend<.1).

The sampled population exhibits disparities in CRC compared to the general population, and cultural characteristics are related to odds of endoscopy. Findings warrant culturally tailored CRC screening initiatives for American Indians.