Table 1.

Studies of cancer outcomes among persons dually enrolled in Medicaid and Medicare

Study	Sample	Design	Outcomes	Results
Bradley et al. 2008 (a)	2,626 older patients with local and regional stage NSCLC	Retrospective cohort	Receipt of resection, chemotherapy, radiation therapy, and survival	Dually eligible patients were half as likely to undergo resection as Medicare patients (P<0.001) and were more likely to receive radiation than Medicare patients. Surgically treated dually eligible patients had slightly poorer survival as compared with that of Medicare patients
Bradley et al. 2008 (b)	103,808 patients in Michigan Tumor Registry with incident female breast, prostate, colorectal, and lung cancer	Population based cohort	Cancer incidence	In dually eligible patients enrolled 12 or more months before the diagnosis, an excess cancer incidence was observed for black patients relative to white patients in every cancer site examined except for lung cancer
Shugarman et al. 2008	26,073 Medicare beneficiaries age ≥65 years diagnosed with lung cancer	Retrospective cohort	Survival	Increasing age, comorbidity, Medicaid enrollment, and having been diagnosed with stage 3 or state 4 lung cancer were associated with increased mortality risk
Koroukian et al. 2011	Patients with incident breast, prostate, or colorectal cancer in Ohio, age ≥65 years_	Cross-sectional	Unknown stage/unstaged cancer, and distant stage at diagnosis	Dually eligible patients were more likely to have unknown stage/unstaged breast cancer (OR 1.43, 95% CI: 1.02–2.0), and more likely to have distant stage colorectal cancer (OR 1.74, 95% CI: 1.12–2.70)
Koroukian et al. 2012	2,568 patients with incident breast, colorectal, or prostate cancer in Ohio	Retrospective cohort	Recommended cancer treatment	Dual Medicare-Medicaid status was associated with a lower likelihood of receiving definitive treatment for colorectal cancer (OR 0.60, 95% CI: 0.38–0.95) but not for breast or prostate cancer
Manzano et al. 2014	30,199 patients with gastrointestinal cancer in Texas	Retrospective cohort	Unplanned hospitalization	Unplanned hospitalization was associated with black race; residing in census tracts with poverty levels >13.3%; esophageal, gastric, and pancreatic cancer; advanced disease stage; comorbidity; and dual eligibility for Medicare and Medicaid (P<0.05 in each instance)
Warren et al. 2015	1,200 Medicare patients with incident cancer of the breast (stage 11B to III), colon (stage III), rectum (stage II to III), lung (stage II to IV), or ovary (stage II to IV)	Retrospective observational	Consultation with an oncologist and receipt of chemotherapy	Dual-eligible patients were less likely to receive chemotherapy than were Medicare patients with private insurance
Doll et al. 2015	4,522 women age >65 years dually enrolled in Medicare and Medicaid, with cancer of the uterus, ovary, cervix, or vulva/vagina residing in North Carolina	Population based cohort	All-cause mortality and stage at diagnosis	Dual enrollees had increased all-cause mortality overall (HR 1.34, 95% CI: 1.19–1.49) and within each cancer site. Increased odds of advanced stage disease at diagnosis was only present in uterine cancer (OR 1.38, 95% CI: 1.06–1.79)
Guadagnolo et al. 2015	69,572 patients dying of cancer in Texas	Retrospective cohort	Receipt of chemotherapy and radiation therapy, acute care, and costs	Medicaid patients were more likely to receive chemotherapy and radiation therapy, and more likely to have >1 emergency room visit than Medicare patients (OR 5.27, 95% CI: 4.76–5.84). Dual eligibles were more likely to have >1 emergency room visit than Medicare-only beneficiaries (OR 1.19, 95% CI: 1.07–1.33). Costs were higher for non-white Medicare, Medicaid, and dually eligible patients compared to white Medicare enrollees
Parikh-Patel et al. 2017	763,884 persons with breast, ovary, endometrium, cervix, colon, lung, or gastric cancer in California	Retrospective cohort	Recommended radiation, chemotherapy, or surgery	Persons with Medicaid or Medicare-Medicaid dualeligible coverage and the uninsured had lower odds of receiving recommended radiation and/or chemotherapy or surgery for breast, endometrial, and colon cancer, relative to those with private insurance
Ratnapradipa et al. 2017	10,618 patients age ≥65 years who underwent colon cancer resection	Retrospective cohort	Laparoscopic or open resections for colon cancer	Medicare-Medicaid dual enrollment, age ≥85 years, and higher tumor stage and grade were associated with receipt of laparoscopic surgery
Hess et al. 2017	1,452 patients with NSCLC who were treated with erlotinib	Retrospective cohort	Treatment duration	Low income subsidy status, having Medicare insurance, dual eligibility, and higher erlotinib out of pocket costs were associated with longer treatment duration
Somayaji et al. 2018	262 adults having a lung biopsy in 8 counties in Western New York region	Retrospective cohort	Outpatient and emergency department use, survival time	Age and the number of comorbidities predicted outpatient use and the number of comorbidities predicted emergency department use in patients with lung cancer. Patients with lung cancer who received a lung biopsy by a Commission on Cancer accredited organization had a longer time of survival from the biopsy event

CI, confidence interval; OR, odds ratio; HR, hazards ratio; NSCLC, non-small cell lung cancer.