WASHINGTON – More than one-third of U.S. rheumatoid arthritis patients report using alternative medicine, such as fish oil and glucosamine, at some time after their diagnosis.
However, only 10% of these patients stick with these complementary and alternative (CAM) therapies long term, Dr. Peri H. Pepmueller reported in a poster presentation at the annual meeting of the American College of Rheumatology.
This finding means that rheumatologists "need to ask" about the use of these alternative medicines, Dr. Pepmueller said in an interview.
"I think we can counsel patients that if they want to take them, [they should] take them in addition to the prescription medications," she said.
Dr. Pepmueller of St. Louis University and her colleagues looked at data from the CORRONA (Consortium of Rheumatology Researchers of North America) registry, a multicenter, longitudinal prospective database in the United States with more than 30,000 patients.
The researchers assessed reported CAM use, including the use of fish oil and glucosamine/chondroitin supplements. They also assessed the use of borage seed oil, evening primrose oil, and flax seed oil, the presumed effect of which is to decrease inflammation, Dr. Pepmueller said.
"The oils ... have been shown in many studies to have an anti-inflammatory effect on a variety of chronic conditions in which inflammation is thought to play a role," she said.
In total, 11,970 patients were included in the final analysis. All had at least 2 years of follow-up and at least three visits.
The researchers defined the use of CAM as the use of any of the above-listed therapies within 2 years of their first recorded visit. "Long-term" therapy was defined as the use of the same therapy at either three consecutive visits or all visits in 1 year.
They found that 35.2% of patients reported using one of the complementary therapies looked at, but only 10.8% reported long-term use.
Fish oil was the most commonly reported supplement, used by 27.3% of the cohort.
The next most common supplement was glucosamine/chondroitin, used by a reported 13.6% of the cohort, followed by flax seed oil (3.3%), evening primrose oil (2.1%), and borage seed oil (1.4%).
Dr. Pepmueller then analyzed which, if any, demographic and disease factors predicted complementary alternative medicine use.
Of current smokers, the odds that they would ever use CAM were 0.70 (95% confidence interval, 0.62-0.79; P less than .0001) and the odds of long term CAM use was .71 (95% CI, 0.57-0.87; P less than .05), based on findings of the multivariate analysis.
Patients with education levels of high school or less were also less likely to try complementary medicines, with an OR of 0.69 ( 95% CI, 0.63-0.75; P less than .0001), versus patients with any college-level education.
Geographically, patients in the Western United States were more likely to try complementary medicine alternatives, compared with Midwestern patients (OR, 1.49; 95% CI, 1.29-1.72; P less than .0001), while patients in the Northeastern United States were even less likely than their Midwestern counterparts to try these alternatives (OR, 0.83; 95% CI, 0.74-0.93; P less than .0001 for both values).
On the other hand, while disease duration and severity were not significant predictors of complementary medicine use in a multivariate analysis, unadjusted models showed that a longer duration and a greater number of swollen and tender joints, as well as patient- and physician-assessed disease severity, were all associated with decreased use of complementary medicine.
Dr. Pepmueller also pointed to articles detailing some of the risks involved with alternative medicines, including reports of increased levels of low-density lipoprotein cholesterol levels with fish oil consumption (Rheum. Dis. Clin. North Am. 2011;37:77-84).
Medication interactions are also possible. For example, there have been reports of fish oil potentiating the effects of coumadin.
Dr. Pepmueller stated that she had no relevant financial disclosures; a coinvestigator reported funding from Axio Research.