The Association Between Medicare Low-income Subsidy and Anticancer Treatment Uptake in Advanced Lung Cancer
A partir des données des registres américains des cancers et de la base Medicare portant sur 19 746 patients atteints d'un cancer du poumon non à petites cellules de stade avancé et âgés de plus de 65 ans, cette étude analyse l'impact des aides financières sur leur décision de prendre des traitements anticancéreux dispensés par voie orale et sur le moment du début du traitement
Background : High out-of-pocket costs may impact anticancer treatment uptake. Low-income subsidies (LIS) can reduce patient out-of-pocket cost for Medicare Part D-covered treatments. We examined whether LIS increased uptake and reduced time to initiate orally-administered anticancer drugs in patients with advanced non-small cell lung cancer (NSCLC). Methods : Using SEER-Medicare data, we identified older adults (aged 65+) diagnosed with advanced NSCLC from 2007-2013 and categorized them as full, partial, or non-LIS. We used propensity-score weighted (IPTW) Cox proportional hazards regression to assess the likelihood of and time to initiate Part D treatments. Part B medication uptake was our negative control since supplemental insurance reduces out-of-pocket costs for those drugs. All statistical tests were two-sided. Results : Among 19,746 advanced NSCLC patients, approximately 10% initiated Part D treatments. Patients with partial or no subsidies were less likely to initiate Part D treatments than those with full subsidies (Partial LIS vs. Full LIS: HRIPTW=0.77, 95%CI=0.62-0.97; Non-LIS vs. Full LIS: HRIPTW=0.87, 95%CI=0.79-0.95). Time to initiate Part D treatments was also slightly shorter among full-LIS patients [Full LIS mean=10.8 months (SD = 0.04), Partial LIS:mean =11.3 months (SD = 0.08), Non-LIS mean=11.1 months (SD = 0.03), p<.001]. Conversely, patients with partial or no subsidies had shorter time to initiation of Part B drugs. Conclusion : Patients receiving full low-income subsidies had higher orally-administered anticancer treatment uptake than patients without subsidies. Notably, patients with partial subsidies had the lowest treatment uptake, likely due to their low incomes combined with high expected out-of-pocket spending. High out-of-pocket costs for Part D medications may be a barrier to treatment use for patients without full low-income subsidy.