Dietary Outcomes in Osteoarthritis Disease Management

Carol J. Henderson, PhD, RD
Department of Nutrition
Georgia State University 
Atlanta, GA

Discussion with Patients

Dietary supplements or nutriceuticals sold in the United States encompass a wide range of products including vitamins, minerals, amino acids, herbs, botanicals, and other substances. Dietary supplements are not regulated by the Food and Drug Administration in the same manner as prescription drugs, therefore, the consumer has no assurance that a product contains what is stated on the label or that it does not contain undesirable elements not mentioned on the label.

It is important to realize that the use of dietary supplements among the elderly is high compared to the general population. Based on 1988 to 1994 NHANES data, 56% of middle-aged and older adults consume at least one daily dietary supplement vs 40% in the general population. When discussing the use of dietary supplements, it is imperative to discuss the amount of scientific evidence supporting the safety and benefits of dietary supplement use. Health care providers need to be knowledgeable about, or have access to, authoritative sources of information about dietary supplements. All supplements are not safe, and the inappropriate use of some supplements may result in adverse health consequences.

It is not uncommon for physicians to prescribe several medications to treat patients with musculoskeletal and rheumatic diseases. In addition, other medications may be prescribed to manage other underlying conditions. Patients taking dietary supplements do so for a variety of reasons, therefore becoming familiar with supplements that interact with frequently prescribed medications can prove useful in clinical practice. Table 1 lists commonly used drugs and known interactions with various dietary supplements/herbal compounds.

Inconsistencies arise due to lack of product standards. Concerns include possible prescription drug interactions with dietary supplements, potential adverse effects that may pose pre-operative dangers, interactions with over-the-counter medications, contamination of preparations, and mislabeling.

Many rheumatologists believe that it is premature to universally recommend these agents to all patients with OA until better studies are conducted to determine mechanism of action, optimal dosing, long-term effects on disease modification and improved regulations to insure purity, reliability and consistency in the active ingredient.

Information regarding the use of dietary supplements that is available on the Internet may be misleading. Consumers may be easily be misled by vendor's claims that dietary supplements can treat, prevent, diagnose, or cure specific diseases, despite regulations that prohibit such statements. Efforts need to be made to direct patients to appropriate resources and to provide patients with an understanding of how to examine the quality of information used to make an informed decision about the use of dietary supplements. Table 2 provides reliable resources for more information on use of dietary supplements.