Disparities in stage at diagnosis, treatment, and survival in nonelderly adult patients with cancer according to insurance status

Abstract

Purpose: The purpose of this study was to determine the association of insurance status with disease stage at presentation, treatment, and survival among the top 10 most deadly cancers using the SEER database.

Patients and methods: A total of 473,722 patients age 18 to 64 years who were diagnosed with one of the 10 most deadly cancers in the SEER database from 2007 to 2010 were analyzed. A Cox proportional hazards model was used for multivariable analyses to assess the effect of patient and tumor characteristics on cause-specific death.

Results: Overall, patients with non-Medicaid insurance were less likely to present with distant disease (16.9%) than those with Medicaid coverage (29.1%) or without insurance coverage (34.7%; P < .001). Patients with non-Medicaid insurance were more likely to receive cancer-directed surgery and/or radiation therapy (79.6%) compared with those with Medicaid coverage (67.9%) or without insurance coverage (62.1%; P < .001). In a Cox regression that adjusted for age, race, sex, marital status, residence, percent of county below federal poverty level, site, stage, and receipt of cancer-directed surgery and/or radiation therapy, patients were more likely to die as a result of their disease if they had Medicaid coverage (hazard ratio [HR], 1.44; 95% CI, 1.41 to 1.47; P < .001) or no insurance (HR, 1.47; 95% CI, 1.42 to 1.51; P < .001) compared with non-Medicaid insurance.

Conclusion: Among patients with the 10 most deadly cancers, those with Medicaid coverage or without insurance were more likely to present with advanced disease, were less likely to receive cancer-directed surgery and/or radiation therapy, and experienced worse survival.

Fig 1.

Proportion of patients presenting with localized, regional, or distant disease by insurance status. All P < .001. For non-Hodgkin lymphoma (NHL), Ann Arbor stage I disease was considered localized, stage II to III disease was considered regional, and stage IV disease was considered distant.

Fig 2.

Forest plot depicting odds ratios (ORs) and 95% CIs for not undergoing cancer-directed surgery and/or receiving radiation therapy for patients with nonmetastatic disease with Medicaid coverage and those with no insurance as compared with patients with non-Medicaid insurance. All sites controlled for age, race, sex, marital status, residence (urban v rural), and percent of county below federal poverty level.

Fig 3.

Unadjusted Kaplan-Meier curve illustrating cause-specific survival by insurance status for patients with one of 10 most deadly cancers. P < .001.

Fig 4.

Forest plot depicting hazard ratios and 95% CIs for cancer-specific death for patients with Medicaid coverage and those with no insurance as compared with patients with non-Medicaid insurance. All sites controlled for age, race, sex, marital status, stage (local, regional, or distant), residence (urban v rural), percent of county below federal poverty level, and undergoing cancer-directed surgery and/or receiving radiation therapy. Breast and prostate sites also controlled for estrogen receptor and prostate-specific antigen and Gleason score, respectively. NHL, non-Hodgkin lymphoma.

Fig A1.

Proportion of patients with nonmetastatic disease treated with cancer-directed surgery and/or radiation therapy by insurance status. NHL, non-Hodgkin lymphoma.