Analyzing Insurance Status and Cancer Survival

New Jersey State Cancer Registry

Previous studies suggest that having no health insurance or inadequate insurance coverage can be a barrier to accessing cancer screening or receiving appropriate cancer treatment. Such barriers have been shown to impact cancer patient survival. A study looked for links between health insurance status and cancer patient survival in New Jersey.

The New Jersey State Cancer Registry provided data for female breast, colorectal, lung, non-Hodgkin lymphoma, and urinary bladder cancer cases diagnosed between 1999 and 2004 among persons aged 18 to 64 years. The cases were followed to obtain vital status through 2005. Cox proportional hazards models were fit for each cancer site separately to estimate the risk of cancer death for patients in three insurance categories (Medicaid, private, or uninsured) after adjusting for age, stage at diagnosis, and race/ethnicity.

Thirteen percent of the cases in the registry diagnosed between 1999 and 2004 had an unknown insurance payer. To improve the completeness of insurance status information, registry staff matched cancer cases without insurance information to Hospital Patient Discharge Uniform Billing files. Matching reduced the percentage of cases with an unknown payer to about 7%.

For the five cancers, uninsured patients had a significantly higher probability of cancer death than privately insured patients. Medicaid-insured patients also had a significantly higher probability of cancer death than privately insured patients for four cancers, and a non-significantly higher probability for bladder cancer. These results confirm previous findings that patients without private health insurance have worse cancer survival. They were presented at the 2009 North American Association of Central Cancer Registries’ conference in San Diego.