Distance-to-care: Stage at diagnosis for New Mexico (NM) residents with colorectal cancer (CRC).
421 Background: CRC is a leading cause of morbidity and mortality among NM’s American Indians, Hispanics, and non-Hispanic whites. Previous studies have shown that rural residents are more likely than urban dwellers to be diagnosed with late stage disease. Geographically New Mexico is the 5th largest state with a population of 2 million, many of whom reside in rural regions. This study was designed to characterize the association between distance-to-care and stage of disease at diagnosis in NM. Methods: The population-based NM Tumor Registry was used to identify records for all incident cases of CRC between 2001-2008. Latitude and longitude were determined for the place of residence for cancer cases and for the facility where each case was diagnosed. The “Great Circles” algorithm was used to estimate the distance from place of residence to the diagnosing facility. The percentage of cases diagnosed with early stage vs. other stages (i.e., regional, distant, and unknown stages-combined) was assessed by quartile of distance-to-care with the use of the chi-squared test for trend. Multiple logistic regression was used to characterize the association between stage and quartile of distance-to-care while controlling for other factors know to be associated with stage at diagnosis. Results: Analysis was based on 6,291 incident cases of CRC that were diagnosed among NM residents. Latitude and longitude for both place of residence at diagnosis and location of diagnosing facility were available for 4,385 (69.7%) of all incident cases. The percentage of cases diagnosed at early stage was inversely related to the distance between the place of residence at diagnosis and the facility where the cancer was diagnosed, as follows: 41.4% of cases in Quartile 1 (shortest distance-to-care); 39.9% in Quartile 2; 37.8% in Quartile 3; and 35.3% in Quartile 4 (p=0.002).By multiple logistic regression, distance-to-care was a significant predictor of stage at diagnosis after adjustment of sex, age and race/ethnicity. Conclusions: Rural residents of NM who must travel relatively long distances to receive medical care are at increased risk of being diagnosed at late stage colorectal cancer.