A population-based study of survival among elderly persons diagnosed with colorectal cancer: does race matter if all are insured? (United States)

Objectives: Racial disparities in colorectal cancer (CRC) outcomes exist. Insurance coverage might impact access to care and thus processes and outcomes of care. We examined the effect of race on CRC outcomes in a population-based study of elderly Tennesseeans who had identical healthcare coverage - simultaneous enrollment in both Medicaid and Medicare. Methods: The study cohort consisted of all persons dually enrolled in both Tennessee Medicaid and Medicare who were hospitalized with an incident CRC between 1984 and 1994 and whose medical records were available for review. Information confirming the diagnosis and staging was obtained by review of hospital records. Administrative data from the Tennessee Medicaid database identified important medical co-morbidities and determined which patients received chemotherapy and radiotherapy. We ascertained vital status though 2001 by a search of state and national death certificates using the National Death Index. Results: 697 white patients and 272 black patients were identified with incident CRC. Blacks were slightly less likely to be diagnosed with localized disease than whites (45.2% versus 56.1%, p < 0.01). In a Cox-regression model that controlled for stage and co-morbidities, there was no racial difference in overall mortality (HR for blacks 0.95, 95% CI: 0.81-1.11). Blacks were less likely to have surgery (86% versus 91%, p = 0.02). Chemotherapy (for stage III or greater) or radiation therapy for rectal cancer was not used as frequently as expected in this elderly population. Conclusions: In this population-based study of elderly Tennesseans covered by both Medicaid and Medicare, there were no significant differences in outcomes, raising the possibility that 'equal coverage' leads to more equal outcomes.