Use of complementary medications among older adults with cancer.

BACKGROUND: Little is known about complementary medication use among older adults with cancer, particularly those who are receiving chemotherapy. The objective of this study was to evaluate the prevalence of complementary medication use and to identify the factors associated with its use among older adults with cancer. METHODS: The prevalence of complementary medication use (defined as herbal agents, minerals, or other dietary supplements, excluding vitamins) was evaluated in a cohort of adults aged ≥65 years who were about to start chemotherapy for their cancer. The associations between complementary medication use and patient characteristics (sociodemographics; comorbidities; and functional, nutritional, psychological, and cognitive status), medication use (number of medications and concurrent vitamin use), and cancer characteristics (type and stage) were analyzed. RESULTS: The cohort included 545 patients (mean age, 73 years; range, 65-91 years; 52% women) with cancer (61% stage IV). Seventeen percent of these patients (N = 93) reported using ≥1 complementary medication; the mean number of complementary medications among users was 2 (range, 1-10 medications). Complementary medication use was associated with 1) earlier cancer stage (29% had stage I-II disease vs 17% with stage III-IV disease; odds ratio [OR], 2.05; 95% confidence interval [CI], 1.21-3.49) and 2) less impairment with instrumental activities of daily living (OR, 1.39; 95% CI, 1.12-1.73). CONCLUSIONS: Complementary medication use was reported by 17% of older adults with cancer and was more common among those who had less advanced disease (i.e., those receiving adjuvant, potentially curative treatment) and higher functional status. Further studies are needed to determine the association between complementary medication use and cancer outcomes among older adults.