Abstract
IMPORTANCE: Older adults with metastatic solid cancers experience substantial treatment burdens. Advances in cancer therapeutics and evolutions in care over the years have changed the experience of cancer diagnosis and treatment, but it is unknown how health care contact days have evolved over time. OBJECTIVE: To assess the burden of and trends in health care contact days among older adults diagnosed with 4 common metastatic cancers. DESIGN, SETTING, AND PARTICIPANTS: This cohort study used the Surveillance, Epidemiology, and End Results-Medicare linked database to identify traditional Medicare beneficiaries 66 years and older who were diagnosed with metastatic breast, colorectal, lung, and prostate cancers from January 2008 to February 2019. Analyses were conducted from February 2024 to January 2025. EXPOSURES: Cancer type and year of diagnosis. MAIN OUTCOMES AND MEASURES: Health care contact days (sum of ambulatory [days with a clinician visit, test, imaging, procedure, or treatment] and institutional [days in a hospital, emergency department, skilled nursing facility, or inpatient hospice] days) in the year after diagnosis were assessed. Changes in contact days over time were examined using multivariable negative binomial regression models. RESULTS: A total of 55 806 beneficiaries (14 827 [26.6%] diagnosed at 71-75 years of age; 29 347 [52.6%] male) with metastatic cancer (6495 breast, 10 232 colorectal, 27 340 lung, and 11 739 prostate) who survived 1 year or more after diagnosis were studied. In the year after diagnosis, beneficiaries with colorectal cancer had the highest mean (SD) contact days (62.9 [48.1]), followed by those with lung (60.2 [47.0]), breast (48.7 [47.9]), and prostate (40.1 [42.4]) cancers. Across all cancer types, mean contact days increased from 2008 to 2019 with a prominent increase in ambulatory days from 2016 onward; the largest increase in contact days was observed for breast cancer (44.9 [95% CI, 38.7-52.2] to 57.6 [95% CI, 46.9-70.8]). CONCLUSIONS AND RELEVANCE: This cohort study of older traditional Medicare beneficiaries who were diagnosed with common metastatic cancers found a mean of 40.1 to 62.9 health care contact days in the year after diagnosis. Health care contact days increased from 2008 to 2019, suggesting that treatment advancements and/or care inefficiencies may have imposed additional burdens on beneficiaries.