Monday, July 31, 2017

Asking patients about herbal dietary supplements

- Jennifer Middleton, MD, MPH

The world of herbal dietary supplements can feel murky to physicians, as many supplements have limited rigorous data to back their efficacy and safety. Despite physicians' common reservations, though, an estimated 40.6 million US adults used these supplements in 2012. The authors of a current AFP article on Common Herbal Dietary Supplement-Drug Interactions cite studies showing that only 1 in 3 patients taking a supplement have informed their physician. If we are to help patients navigate the world of supplements safely, we first must know what they are taking.

Several studies have attempted to categorize which patients are more and less likely to discuss their supplement use with physicians. Women are more likely to inform their physicians of supplement use than men, and adults aged 45-64 are more likely to inform than adults aged 18-24. Asian Americans and Hispanic Americans are less likely to inform their physicians than other US ethnic groups. Patients who believe that supplements are safer than conventional medicine and/or not do consider them "medications"  are unlikely to report their use as well. Unfortunately, patients are often unaware of the risks that may exist with supplements.

Knowledge of herbal dietary supplements among physicians is varied, as are attitudes about their use. Physicians with negative views are more likely to advise patients against supplement use. Unfortunately, this advice can discourage patients from further disclosing supplement use at future visits. Physicians may also hesitate to broach the subject with patients because of their own limited knowledge, and, in general, physicians are willing to learn more about supplements and other complimentary medicine therapies given the opportunity.

Several potential solutions exist. Raising awareness of the prevalence of supplement use, and many patients' reticence to discuss it, is a necessary first step. Improving our knowledge of common therapies' safety and efficacy is another; the AFP article mentioned above includes a table (Table 3) with several useful resources, and there's also an AFP By Topic on Complimentary and Alternative Medicine. Since less than half of physicians ask patients about their supplement use, simply asking our patients at every visit is also important as most patients prefer for their physician to ask rather than bring up supplement use themselves. Demonstrating a nonjudgmental attitude may encourage patients to give us honest responses. Communication and cultural competence training may also help physicians more deeply understand and discuss varied health traditions with patients.

How do you discuss supplement use with patients? Are there resources that you have found especially useful?