More than 40 million U.S. adults (17.9 percent) report using dietary supplements (DS), according to the 2012 National Health Interview Survey. However, a Boston Medical Center (BMC) study revealed that just 6 percent of respondents were asked by their physicians about DS use, disclosed that use to a physician, and had their DS use documented. The findings are published in the current issue of the journal Patient Education and Counseling.

Dietary supplements are recognized in The Joint Commission's National Safety Goals, which requires documentation of patients' DS use and over-the-counter drugs in their health record, just like any other medication. According to the 1994 Dietary Supplement Health and Education Act (DSHEA), a DS is intended to supplement the diet, and contains one or more dietary ingredients including, but not limited to: vitamins, minerals, herbs or other botanicals, amino acids, and other substances or their constituents.

"If clinicians are unaware of possible drug-DS reactions, they may unknowingly provide a treatment plan or prescribe medications that could have an adverse reaction or interactions with the dietary supplement," said Paula Gardiner, MD, MPH, assistant director for the Program for Integrative Medicine and Health Care Disparities, who is the study's lead author. "Dietary supplements also affect physiological processes in the body and could have an impact on medical procedures like surgery, chemotherapy, blood work and many other treatments or procedures."

Specific patient populations, especially the elderly, those who are frequently hospitalized, and those who take prescription medications may be more susceptible to drug-DS interactions or adverse reactions due to acute or chronic illnesses, according to the study.

In the analysis of 558 hospitalized, prescription medication users who use a dietary supplement, 20 percent were asked about supplement use by a provider, and only 18 percent reported disclosing DS use to a provider. Although 36 percent had documentation of DS use in the medical chart, the study reports that documentation decreases with increasing patient age, and is lower among those who self-identify as Hispanic or a race other than Caucasian. Forty-eight percent reported that they would continue to use their supplements after discharge.

"Research has shown that some of the reasons patients do not disclose DS use is because they either don't know that physicians need the information, or sometimes there's a fear of being judged by a clinician," said Gardiner, who also is an assistant professor in the Department of Family Medicine at Boston University School of Medicine.

Findings by additional studies, in other hospital settings, also demonstrate a discrepancy in DS documentation. Among patients in a general internal medicine and geriatric service, 75 percent reported that no physician asked about DS use during admission.

"Medical school faculty have the opportunity, and in fact the obligation, to educate tomorrow's physicians about the importance of DS dialogue with patients of all ages and cultural backgrounds," Gardiner said. "Physicians need to establish a formalized approach to DS documentation to help prevent adverse reactions from dietary supplement-prescription medication interactions and ultimately to improve outcomes."