To determine the prescribing practices, laboratory monitoring protocols, and perceived barriers of United States rheumatologists in prescribing tumor necrosis factor (TNF) inhibitors in rheumatoid arthritis (RA).
A survey questionnaire was mailed to 1970 rheumatologists who were randomly selected from a national sample of 3008 rheumatologists. A one-page non-response questionnaire was mailed to approximately 200 randomly selected non-responding rheumatologists to assess non-response bias.
Two mailings yielded a response rate of 22.3% (428 completed, usable surveys out of 1922 deliverable surveys). Rheumatologists reported using all three agents in patients with moderate RA (82-87%), severe RA (94-96%), and in newly diagnosed and mild RA patients (10-18%). In patients with severe RA who inadequately responded to methotrexate, 91% of rheumatologists reported using a TNF inhibitor with one other disease modifying anti-rheumatic drug. Over 94% of rheumatologists reported switching patients from one TNF inhibitor to a different TNF inhibitor due to inadequate response or side effects. Most rheumatologists (96%) ordered the purified protein derivative test for tuberculosis, with almost 82% conducting this test at baseline. Costs to patients and insurance coverage were perceived as major barriers to prescribing these agents although the perception was slightly lower with infliximab than with adalimumab or etanercept.
The use of TNF inhibitors is not restricted to patients with moderate and severe RA. Rheumatologists are fairly similar in their utilization of the three TNF inhibitors although some variation exists in terms of laboratory practices and perceived barriers regarding the use of these agents.