The effect of medicare health care delivery systems on survival for patients with breast and colorectal cancer.

BACKGROUND Two of the most common types of health care delivery systems in the U.S. are fee-for-service (FFS) and managed care systems such as health maintenance organizations (HMO). Differences may exist in patient outcomes depending on the health care delivery system in which they are enrolled. We evaluated differences in the survival of patients with breast and colorectal cancer at diagnosis between the two Medicare health care delivery systems (FFS and HMO). METHODS We used a linkage of two national databases, the Medicare database from the Centers for Medicare and Medicaid Services, and the National Cancer Institute's Surveillance, Epidemiology, and End Results program database, to evaluate differences in demographic data, stage at diagnosis, and survival between breast and colorectal cancer over the period 1985 to 2001. RESULTS Medicare patients enrolled in HMOs were diagnosed at an earlier stage of diagnosis than FFS patients. HMO patients diagnosed with breast and colorectal cancer had improved survival, and these differences remained even after controlling for potential confounders (such as stage at diagnosis, age, race, socioeconomic status, and marital status). Specifically, patients enrolled in HMOs had 9% greater survival in hazards ratio if they had breast cancer, and 6% if they had colorectal cancer. CONCLUSIONS Differences exist in survival among patients in HMOs compared with FFS. This is likely due to a combination of factors, including but not limited to, earlier stage at the time of diagnoses.