Abstract 4224: Psychotropic polypharmacy during the initial phase of care among cancer patients in the United States
Authors: Vyas Ami M. , Kogut Stephen J. , Aroke Hilary , Buchanan Ashley 
Published: August 2018

Abstract
Objectives: Limited evidence exists regarding the rates of psychotropic polypharmacy (PP) during the initial phase of care among cancer patients. We describe the characteristics, rates of PP and its predictors during the initial phase of care among cancer patients using administrative claims data.
Methods: A retrospective cohort study was conducted in patients age 18 and above diagnosed with the most commonly occurring cancers (breast, prostate, lung, colorectal) during 2011-2012 using the Optum ClinformaticsTM Data Mart (OptumInsight, Eden Prairie, MN) commercial claims database. PP was defined as concurrent use of two or more psychotropic medications for at least 90 days during the initial phase of care (defined as the first year after cancer diagnosis). Psychotropic medications included antidepressants, antipsychotics, anticonvulsants, anxiolytics-sedatives-hypnotics, and central nervous system stimulants/psychostimulants. The average number of psychotropic medications per patient with PP during the initial phase of care and the proportion of patients on PP were determined. An adjusted logistic regression identified significant predictors of PP in this vulnerable population.
Results: Among 5,604 cancer patients included in the study, 52.6% had breast cancer, 30.6% had prostate cancer, 11.4% had colorectal cancer and 5.5% had lung cancer. During the initial phase of cancer care, PP was found in 7.4% of cancer patients, with highest among those with lung cancer (14.4%), and least among those with prostate cancer (2.9%). Cancer patients on PP had an average of 10.7 (standard deviation=9.6) psychotropic medications prescriptions during the initial phase of cancer care, with highest among lung cancer patients (mean=12.4) and least among prostate cancer patients (mean=9.4). The significant predictors associated with an increased risk of PP were gender (adjusted odds ratio (AOR) for females=2.1, 95% confidence interval (CI):1.29, 3.41), age (AOR for age 55-64 years=1.7, 95% CI: 1.09, 2.65), colorectal cancer (AOR=2.18; 95% CI:1.29, 3.69), lung cancer (AOR=2.46; 95% CI:1.39, 4.35), and presence of psychiatric (AOR for two or more psychiatric conditions=11.7, 95% CI: 6.75, 20.3) and physical chronic conditions (AOR for two or more physical conditions=2.2, 95% CI: 1.63, 3.05).
Conclusion: Psychotropic polypharmacy differed by type of cancer, and it was highly prevalent among those with lung, breast and colorectal cancer patients during their initial phase of care. These findings underscore the importance of evidence-based psychotropic prescribing and close surveillance of adverse drug interactions between psychotropic medications and between psychotropic medications and anti-cancer treatment regimen, in order to improve quality of care and clinical outcomes in this vulnerable population.
Citation Format: Ami M. Vyas, Stephen J. Kogut, Hilary Aroke, Ashley Buchanan. Psychotropic polypharmacy during the initial phase of care among cancer patients in the United States [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4224.