Insurance status linked to survival benefit in cancer treatment trials
Patients with cancer who either had Medicaid or no health insurance derived smaller benefits from experimental therapies than standard therapies in clinical trials, according to results of a meta-analysis published in JAMA Network Open.
Better understanding of the quality of survivorship care — including supportive and post-treatment care — received by patients with suboptimal insurance could help explain how external factors may affect outcomes, researchers noted.
“A patient’s insurance coverage seems to be related to the extent to which they benefit from new experimental treatments tested in trials,” Joseph M. Unger, PhD, Southwest Oncology Group (SWOG) health services researcher and biostatistician at Fred Hutchinson Cancer Research Center, said in a press release. “Our findings highlight the importance of policies that would provide more Americans insurance coverage and underline the importance of improving that coverage.”
Few new treatments tested in randomized phase 3 cancer trials improve OS. Understanding whether treatment benefits are consistent across patient groups is necessary to inform guideline care. However, individual trials are designed to assess the benefits of experimental treatments among all patients and can be too small to determine whether the benefits apply to demographic or insurance subgroups, according to study background.
Unger and colleagues analyzed pooled patient-level data of 10,804 patients with cancer in 19 SWOG Cancer Research Network trials to examine whether positive treatment effects in randomized clinical cancer trials apply to specific demographic or insurance subgroups.
The majority of patients were aged younger than 65 years (67.3%) and female (66.3%). Additionally, 11.4% of patients were black and 5.7% were Hispanic.
Enrollment for the trials occurred from 1984 to 2012, and each trial followed patients for up to 5 years after treatment. All trials reported an OS benefit for patients randomly assigned to the experimental treatment.
Researchers used interaction tests to assess whether the association of treatment with survival differed according to age (65 years or older vs. younger than 65 years), race/ethnicity (minority vs. nonminority populations), sex, or insurance status among patients aged younger than 65 years.
Investigators also examined PFS and RFS.
Results showed no significant added survival benefit associated with experimental therapy for patients with Medicaid or no insurance (HR = 1.23; 95% CI, 0.97-1.56) compared with patients with private insurance (HR = 1.66; 95% CI, 1.44-1.92).
Receipt of experimental treatment appeared associated with reduced added OS benefits among patients aged 65 years or older (HR = 1.21; 95% CI, 1.11-1.32) compared with patients aged younger than 65 years (HR = 1.41; 95% CI, 1.3-1.53). Both groups, however, benefited greatly from the experimental treatments.
HRs for PFS and RFS did not differ by age, sex or race/ethnicity but did differ between patients who had private insurance (HR = 1.74; 95% CI, 1.54-1.97) and those who had Medicaid or no insurance (HR = 1.32; 95% CI, 1.06-1.64).
Most trials were completed before the implementation of insurance exchanges and Medicaid expansion under the Affordable Care Act, which served as a limitation to this study.
“People with fewer financial resources have access to fewer health care resources, which can have a persistent, negative influence on their health,” Unger said in a press release. “Patients in trials having no or limited insurance may not have the financial means to pay for the extra supportive treatments or post-trial cancer treatments that help people live longer. This could be especially meaningful for understanding treatment benefits if experimental therapy requires more supportive care or is more difficult to adhere to than standard treatment.”