Late stage cancers in a Medicaid-insured population.

BACKGROUND: Medicaid insurance promotes screening for early stage cancers. However, previous research suggests that Medicaid recipients are at risk for late stage disease.
OBJECTIVE: To identify differences in stage of diagnosis between cancer patients enrolled in Medicaid before versus after their disease was identified, as well as differences in diagnostic stage between Medicaid enrollees and other patients.
DESIGN: Analyses of a linked database including information from the 1996 and 1997 Michigan Cancer Registry and Medicaid enrollment files. PATIENTS: All persons ages 25 to 64 diagnosed with incident cases of breast, cervical, colorectal, or lung cancer (n = 5852). Patients enrolled in Medicaid before their cancer diagnosis and those enrolled in the same month or after their diagnosis were identified. MAIN OUTCOME MEASURE: Early (in situ, local) versus late (regional, distant, invasive/unknown) cancer stage at diagnosis was modeled using multivariate logistic regression.
RESULTS: In each site of disease with the exception of breast, persons who enrolled in Medicaid after a cancer diagnosis were approximately 2 to 3 times more likely to have late stage disease compared with persons who were enrolled in Medicaid before the month of diagnosis. Odds ratios (OR) and 95% confidence intervals (C.I.) were: 1.28 (95% C.I. = 0.95, 1.67) for breast cancer, 2.96 (95% C.I. = 1.85, 4.75) for cervical cancer, 2.08 (95% C.I. = 1.30, 3.33) for colorectal cancer, and 3.40 (95% C.I. = 2.13, 5.43) for lung cancer. Relative to non-Medicaid enrollees, Medicaid enrollees were 2 to 5 times more likely to be diagnosed with late stage disease.
CONCLUSIONS: Cancer patients enrolled in Medicaid after their diagnosis were disproportionately likely to have late stage disease relative to patients previously enrolled in Medicaid or non-Medicaid enrollees.