SAN FRANCISCO — Rheumatologists and primary care physicians tend to use different diagnostic tests and prescribe different treatments for fibromyalgia syndrome, survey results indicated.
A large fraction of physicians in both groups did not follow the American College of Rheumatology (ACR) 1990 criteria for diagnosing fibromyalgia, Dr. Terence W. Starz and his associates reported in a poster presentation at the annual meeting of the American College of Rheumatology.
“I don't know what that means,” conceded Dr. Starz, a rheumatologist at the University of Pittsburgh Medical Center. “We've got to adhere to criteria” to develop standards of care, he said in an interview during the poster session.
Questionnaires e-mailed to 199 rheumatologists throughout Pennsylvania and 183 primary care physicians in the southwestern portion of the state were returned by 74 (37%) of the rheumatologists and 89 (49%) of the primary care physicians. Both groups agreed that it takes more time to manage patients with fibromyalgia than other patients.
Rheumatologists were significantly more likely to use ACR criteria to diagnose fibromyalgia (56, or 76%) compared with primary care physicians (50, or 56%). The two groups also differed significantly in the use of tests to measure levels of vitamin D, rheumatoid factor, antinuclear antibody, and anti-cyclic citrullinated peptide (anti-CCP) antibody. They reported similar rates of testing for thyroid function, metabolic profile, and human leukocyte antigen B27.
“We need to determine which ones of those should be utilized, because they're very expensive. A vitamin D level can cost up to $250. Anti-CCP is very expensive. They're not included” in the current ACR diagnostic criteria, Dr. Starz said. “We, as a discipline, need to set out standards for diagnosis.”
Vitamin D levels were ordered by 36 rheumatologists (49%) and 15 primary care physicians (17%). Tests for rheumatoid factor were ordered by 43 (58%) and 68 (76%), respectively. Rheumatologists were more likely to measure anti-CCP level (24, or 32%) than were primary care physicians (5, or 6%) but less likely to test for antinuclear antibody (45, or 61%, compared with 68, or 76%, of primary care physicians).
The two groups reported similar perceptions about the pathophysiology of fibromyalgia. Approximately three-fourths said fibromyalgia is both a medical and psychological condition, less than 20% said it's solely a medical condition, and less than 10% said it's solely a psychological condition, judging from the findings in the research, which was recognized as a “notable poster” by the ACR.
Nearly all physicians in both groups prescribed exercise and physical therapy to treat fibromyalgia, but their use of most other therapies differed significantly.
Cognitive therapy was prescribed by 39 rheumatologists (52%) and 26 primary care physicians (29%). NSAIDs were prescribed by 42 (57%) of the rheumatologists and favored by primary care physicians (75, or 84%). “The data on NSAIDs, though, are not very good for fibromyalgia,” Dr. Starz said.
The primary care physicians also were significantly more likely to use SSRIs (68, or 76%) compared with rheumatologists (42, or 57%).
Rheumatologists were more likely to treat with cyclobenzaprine (64, or 86%), or alpha-2-delta ligands such as gabapentin or pregabalin (64, of 86%), compared with primary care physicians (50, or 56% and 59, or 66%, respectively).
The use of selective norepinephrine reuptake inhibitors for fibromyalgia was similar between groups.
“What's interesting to me is there's not nearly enough focus on sleep hygiene and sleep treatment” for patients with fibromyalgia, Dr. Starz commented.
An estimated 5 million people in the United States have fibromyalgia syndrome, more than the combined total of patients with rheumatoid arthritis (1.3 million), systemic lupus erythematosus (322,000), scleroderma (49,000), polymyalgia rheumatica (228,000), and gout (3 million), he said.
The investigators reported no conflicts of interest.