Use of certain medications known as monoclonal anti- tumor necrosis factor α (TNF-α) antibodies for the treatment of rheumatoid arthritis appears to be associated with an increased risk for herpes zoster (shingles), the painful infection characterized by blisters, according to a study in the February 18 issue of JAMA.
There has been evidence from some studies that patients treated with anti-TNF-α agents are at an increased risk of bacterial infections, but little is known about the risk of viral infections, such as herpes zoster, in patients with rheumatoid arthritis receiving these types of medications. Herpes zoster is one of the most common adverse events reported in clinical trials of anti-TNF-α agents, according to background information in the article. Patients with rheumatoid arthritis are at increased risk of herpes zoster compared with the general population.
Anja Strangfeld, M.D., of the German Rheumatism Research Center, Berlin, and colleagues investigated the association of various rheumatoid arthritis treatments, including anti-TNF-α therapy, with the risk of herpes zoster. The researchers analyzed data from patients who began treatment with adalimumab or infliximab (monoclonal anti-TNF-α antibodies), etanercept (a fusion protein), the monotherapeutic agent anakinra, or when patients changed conventional disease-modifying anti-rheumatic drug (DMARD). Treatment, clinical status and adverse events were assessed by rheumatologists at fixed points during follow-up (of up to three years). A total of 5,040 patients were included in the analysis.
There were 86 cases of herpes zoster among 82 patients. Thirty-nine occurrences could be attributed to treatment with anti-TNF-α antibodies (23 to etanercept, 24 to conventional DMARDs). The researchers found a significant association between herpes zoster and treatment with the monoclonal anti-TNF-α antibodies infliximab and adalimumab, although this risk was lower than the threshold for clinical significance. There was no significant association between herpes zoster and treatment with etanercept, or anti-TNF-α treatment as a class.
A significantly higher risk of developing herpes zoster was found for patients of older age and for treatment with glucocorticoids (steroid hormones that are widely used as anti-inflammatory medications).
"Based on our data, we recommend careful monitoring of patients treated with monoclonal anti-TNF-α antibodies for early signs and symptoms of herpes zoster," the authors conclude.
More information: JAMA. 2009;301:737-744
Source: JAMA and Archives Journals
Explore further: Italy bans Novartis flu vaccine after suspicious deaths