Geographic variation in palliative care delivery among patients diagnosed with metastatic lung cancer in the USA: Medicare population-based study.

The USA has observed a significant increase in the use of palliative care for patients diagnosed with advanced cancer. However, it is unknown how geographic variation affects patients' use of palliative care services. We examined temporal and demographic trends in receipt of and timing of palliative care by state and region. A retrospective cohort study of the Surveillance, Epidemiology, and End Results (SEER)-Medicare database. Study sample included community-dwelling patients aged ≥ 65 years with metastatic lung cancer who were diagnosed between 2001 and 2015. Cochran-Armitage trend test was used to evaluate temporal trends in receipt of and timing of palliative care by states and census region. The proportion of metastatic lung cancer patients who received palliative care ranged from 16.4% in Washington and 16.3% in Connecticut to 6.4% in Louisiana. From 2001 to 2015, use of palliative care increased from 3.2 to 29.8% in the West region, from 3.3 to 31.9% in the Northeast region, from 3.8 to 36.2% in the Midwest region, and from 0.9 to 23.3% in the South region (all P < 0.001). The median time from the date of cancer diagnosis to the date of first palliative care visit varied geographically, from 44 days in Utah to 66 days in California. Hospital-based palliative care was most common in these states. The substantial geographic variation in the use of palliative care suggesting a need for additional research on geographic disparities in palliative care and strategies that might improve state-level palliative care delivery.