Older cancer survivors’ use of biologically based complementary and alternative medicine (CAM): A national, population-based study in the United States

Abstract

9508 Background: The use of CAM is prevalent among cancer patients, including the geriatric population. The prevalent poly- pharmacy in geriatric patients raises the possibility of significant CAM-medication (MED) interactions. Methods: A national population- based sample of community-residing U.S. adults ages 57–85 years were surveyed, which included cancer survivors, defined as anyone with a diagnosis of cancer, excluding skin cancer. Subjects were queried on the use of CAM in the prior 12 months, and interviewers logged, by direct observation, all current MEDs. Biologically based CAM included any nutritional supplements (NS) (e.g., vitamins), nutraceuticals (NTC) (e.g., glucosamine), and herbal medicines (HM) (e.g., garlic). Thomson Micromedex online software was used to determine potential MED interactions. Analyses were weighted when applicable. Results: A total of 3,005 subjects participated (75.5% response rate), of which 373 subjects (12.5%; 95% CI, 11.2–13.8) were cancer survivors with median age of 71 and mean cancer survivorship of 12 years (range 0–56) and used a median of 5 MEDs (range 0–20). 62% (95% CI, 55–69) used biologically based CAM in the prior 12 months, including 24% (95% CI, 18–30) that used HM. Of documented current HM users, 15 of 36 did not report taking any when asked. The most commonly used NTC and HM were glucosamine (34%), chondroitin (23%), and omega-3 fatty acids (19%). 43 of 75 documented current NTC or HM users were at risk for 116 potential MED interactions (NTC-MED and HM-MED: 12%, NS-MED: 43%, and MED-MED: 45%). Of the NTC-MED and HM-MED interactions, Thomson Micromedex identified 3 severe, 8 moderate, and 3 minor interactions. Conclusions: This population-based survey provides the first detailed information on the prevalent use of biologically based CAM by older Americans with cancer. A substantial number taking HM failed to report doing so. Among current users of biologically based CAM, over half of all interactions identified were related to CAM therapies and affected over one-third of these patients. Oncologists’ awareness of CAM use in this population is important for patient education and prevention of MED interactions. No significant financial relationships to disclose.