Impact of incident cancer on short-term coronary artery disease–related healthcare expenditures among Medicare beneficiaries

Background: Healthcare spending for coronary artery disease (CAD)–related services is higher than for other chronic conditions. Diagnosis of incident cancer may impede management of CAD, thereby increasing the risk of CAD-related complications and associated healthcare expenditures. This study examined the relationship between incident cancer and CAD-related expenditures among elderly Medicare beneficiaries. Patients and Methods: A retrospective longitudinal study was conducted using the SEER-Medicare linked registries and a 5% noncancer random sample of Medicare beneficiaries. Elderly fee-for-service Medicare beneficiaries with preexisting CAD and with incident breast, colorectal, or prostate cancer (N512,095) or no cancer (N534,237) were included. CAD-related healthcare expenditures comprised Medicare payments for inpatient, home healthcare, and outpatient services. Expenditures were measured every 120 days during the 1-year preindex and 1-year postindex periods. Adjusted relationship between incident cancer and expenditures was analyzed using the generalized linear mixed models. Results: Overall, CAD-related mean healthcare expenditures in the preindex period accounted for approximately 32.6% to 39.5% of total expenditures among women and 41.5% to 46.8% among men. All incident cancer groups had significantly higher CAD-related expenditures compared with noncancer groups (P,.0001). Men and women with colorectal cancer (CRC) had 166% and 153% higher expenditures, respectively, compared with their noncancer counterparts. Furthermore, men and women with CRC had 57% and 55% higher expenditures compared with those with prostate or breast cancer, respectively. Conclusions: CAD-related expenditures were higher for elderly Medicare beneficiaries with incident cancer, specifically for those with CRC. This warrants the need for effective programs and policies to reduce CAD-related expenditures. Close monitoring of patients with a cancer diagnosis and preexisting CAD may prevent CAD-related events and expenditures.