Complementary medicine and alternative medicine (CAM) is estimated to be a multibillion business in the United States, but people who use it instead of conventional cancer treatment have a 2-fold risk of death, a recent study in JAMA Oncology reported. Patients using or considering CAM are unlikely to discuss it with their doctors, who should proactively inform patients of the risk, the study said.
Complementary medicine and alternative medicine (CAM) is estimated to be a multibillion business in the United States, but those who use it instead of conventional cancer treatment (CCT) have a 2-fold risk of death, a recent study in JAMA Oncology reported. Clinicians need to be aware of this issue, because most patients using or considering CAM are unlikely to discuss it with their doctors, who should proactively inform patients of the risk, the study said.
Patients most likely to pick CAM over CCT are more likely to be middle-aged women with higher education and higher incomes living in the Western part of the country, the study of nearly 2 million people reported. By cancer type, patients are more likely to have breast cancer, followed by colon cancer.
CAM may include herbs and botanicals, vitamins and minerals, traditional Chinese medicine, specialized diets, homeopathy and naturopathy. While some patients use CAM in addition to CCT, finding it improves their quality of life, others may choose it over CCT and refuse traditional medicine.
From 1.9 million patients in the National Cancer Database, researchers compared 258 patients who used CAM with 1032 who didn’t. Patients were included if they were diagnosed with nonmetastatic breast, prostate, lung, or colorectal cancer between 2004 and 2013.
Researchers studied CAM use in addition to at least 1 CCT, which was defined as surgery, radiotherapy, chemotherapy or hormone therapy, looking at overall survival, adherence to treatment and patient characteristics.
CAM use varied by several factors and was associated with refusal of conventional cancer treatment. The survival difference could be mediated by adherence to all recommended CCT.
In the results, 258 patients (199 women and 59 men; mean age, 56 years [interquartile range, 48-64 years]) were in the CAM group, and 1032 patients (798 women and 234 men; mean age, 56 years [interquartile range, 48-64 years]) were in the control group.
Patients who chose CAM did not have a longer delay to initiation of CCT, but they had higher refusal rates of surgery (7% [18 of 258] vs 0.1% [1 of 1031]; P  < .001), chemotherapy (34.1% [88 of 258] vs 3.2% [33 of 1032]; P  < .001), radiotherapy (53% [106 of 200] vs 2.3% [16 of 711]; P  < .001), and hormone therapy (33.7% [87 of 258] vs 2.8% [29 of 1032]; P  < .001).
Use of CAM was associated with poorer 5-year overall survival compared with no CAM (82.2% [95% CI, 76%-87.0%] vs 86.6% [95% CI, 84.0%-88.9%]; P = .001) and was independently associated with greater risk of death (hazard ratio, 2.08; 95% CI, 1.50-2.90) in a multivariate model that did not include treatment delay or refusal. However, there was no significant association between CAM and survival once treatment delay or refusal was included in the model (hazard ratio, 1.39; 95% CI, 0.83-2.33).
Researchers found that, among patients who were receiving at least 1 CCT modality, patients who chose CAM were more likely to refuse at least 1 component of CCT and had a higher risk of death than patients who did not use CAM.
Johnson SB, Park HS, Gross CP, et al. Complementary medicine, refusal of conventional cancer therapy, and survival among patients with curable cancers. [published online July 19, 2018]. JAMA Oncol. doi: 10.1001/jamaoncol.2018.2487.