Real-world direct health care costs associated with psychotropic polypharmacy among adults with common cancer types in the United States

Ami M. Vyas, University of Rhode Island
Stephen J. Kogut, University of Rhode Island
Hilary Aroke, University of Rhode Island

Abstract

BACKGROUND: Psychotropic polypharmacy is not uncommon among cancer patients and may contribute to the increased direct health care cost burden in this population. OBJECTIVE: To estimate average direct health care costs in the year following cancer diagnosis among cancer patients receiving psychotropic polypharmacy compared with those without psychotropic polypharmacy, using a multivariable analysis framework. METHODS: A retrospective cross-sectional study was conducted among patients aged 18 years and older diagnosed with the most commonly occurring cancers (breast, prostate, lung, and colorectal) in the United States during 2011-2012 using the deidentified Optum Clinformatics Data Mart commercial claims database. Psychotropic polypharmacy was defined as concurrent use of 2 or more psychotropic medications for at least 90 days. Direct health care costs in the year following cancer diagnosis were estimated as total medical payments made by the health plans and were derived from claims files. A generalized linear regression model with log-link function and gamma distribution was used to model average direct health care costs, controlling for baseline patient demographic and clinical covariates. RESULTS: Average annual direct health care costs for cancer patients with psychotropic polypharmacy ($53,497; SD $72,590) were higher than those without psychotropic polypharmacy ($38,255; SD $59,844), with an unadjusted average cost difference of $15,242 (P<0.0001). In the adjusted regression model, the average difference in costs shrunk to $5,888 but remained notable. When examined by type of cancer, average direct health care costs for all cancer patients with psychotropic polypharmacy were significantly higher than those for patients without psychotropic polypharmacy, except for colorectal cancer patients. CONCLUSIONS: Overall health care costs were higher among cancer patients with psychotropic polypharmacy compared with those without psychotropic polypharmacy. Our findings support the need for future research to better understand the benefits and risks of psychotropic polypharmacy, given its potential to cause adverse health outcomes and avoidable health care utilization and costs for this vulnerable patient population.