Does using so-called complementary medicine affect cancer patients' survival?
Yale School of Medicine researchers aimed to find out by analyzing a national cancer database. Their findings, published Thursday in JAMA Oncology, offered a troubling answer: Complementary medicine users are more likely than non-users to refuse a conventional cancer treatment — and are more likely to die as a result.
But other experts say Yale's methodology is so flawed that the conclusion is basically a slap at what proponents now prefer to call "integrative medicine" — supportive therapies added to conventional treatment to help manage side effects and enhance quality of life.
"This study is full of so many problems," said Daniel Monti, director of the Marcus Institute of Integrative Health at Thomas Jefferson University. "The fact that JAMA Oncology published it really speaks to the misunderstanding about integrative medicine and the negative bias some of our colleagues have toward it."
As the Yale researchers explain in their article, complementary medicine is a catchall term for practices and products including herbs, vitamins, homeopathy, Chinese medicine, special diets, Reiki, acupuncture, and meditation.
The national database of cancer-patient records that Yale delved into doesn't contain information about use of "complementary medicine." It does, however, say which patients used "Other-Unproven: Cancer treatments administered by nonmedical personnel."
So the Yale researchers decided to define complementary medicine users as patients with that negative-sounding check mark in their record.
"It was either that or we couldn't do the study," said senior author Joseph Yu, a radiation oncologist at Yale Cancer Center. "We thought it was better to make an attempt."
"That is not a definition of complementary medicine used by many people, certainly not by me," said Maurie Markman, president of medicine and science at Cancer Treatment Centers of America, which is known for its integrative approach to care.
While most complementary medicine approaches have not been rigorously studied, the field is not completely unproven. Massage, acupuncture, yoga, and meditation have been shown by past research to improve patients' quality of life, as the Yale researchers point out.
In any case, very few patients in the database fit the Yale researchers' debatable definition of complementary medicine. Out of 1.9 million patients diagnosed with nonmetastatic breast, prostate, lung, or colorectal cancer between 2004 and 2013, only 258 — or 0.01 percent — were users of other-unproven treatments.
But as the Yale paper says, complementary and alternative medicine is a "multibillion-dollar industry in the United States," with surveys estimating that 48 percent to 88 percent of cancer patients incorporate it into treatment.
Finding only 258 users "doesn't in any way comply with anything we know about the cancer population's use of complementary therapies," Monti said. "That suggests there's a methodological problem."
Skyler Johnson, chief resident in radiation oncology at Yale and lead author of the analysis, said, "I think the number is actually much higher. Patients are hesitant to discuss their use of complementary medicine."
To look for an impact on behavior and survival, the Yale researchers compared each of the 258 patients with four patients who were carefully matched in terms of cancer type and stage, age, race, household income, insurance type, and more.
It turned out that the patients who opted for unproven treatments were more likely to refuse a recommended conventional treatment — surgery or radiation or chemotherapy. For example, 53 percent of patients in the unproven treatment group refused radiation, vs, 2 percent in the comparison group.
As a result, the researchers concluded, the complementary medicine users had worse five-year survival rates and were twice as likely to die during the study period.
Markman at Cancer Treatment Centers said he was "very concerned" because the paper unfairly implies that people who use complementary approaches "are somehow associated with refusal of conventional therapies."