BERLIN – Patients who have inflammatory rheumatic diseases and are on anti–tumor necrosis factor therapy have nearly double the risk of herpes zoster when they are compared with patients on disease-modifying antirheumatic drugs, according to the first meta-analysis in these patient populations.
Although the risk of bacterial infection is known to be increased among patients on anti-TNF therapy, less well known is whether the use of anti-TNF agents increases the risk for viral infections, especially herpes zoster, said Dr. Cedric Lukas of the department of rheumatology at Lapeyronie Hospital in Montpellier, France.
Dr. Cedric Lukas
The meta-analysis of literature that was published between 2002 and 2010 involved a review of 655 articles and 134 congress abstracts, of which 22 articles and 28 abstracts eventually were included in the study. The anti-TNF therapies that were investigated included etanercept (Enbrel), adalimumab (Humira), and infliximab (Remicade), which were the agents available at the time.
National registries from the United States, United Kingdom, and other European countries were included in the meta-analysis, including BSRBR (British Society for Rheumatology Biologics Register), BIOBADASER (Spanish Registry of Adverse Events of Biological Therapies in Rheumatic Diseases), CORRONA (Consortium of Rheumatology Researchers of North America), the McDonald cohort of U.S. veterans (Clin. Infect. Dis. 2009;48:1364-71), and RABBIT (the German Rheumatoid Arthritis Observation of Biologic Therapy) were selected for inclusion. After selection for appropriate treatment regimens and diseases, 124, 966 patient years were included.
Upon meta-analysis, Dr. Lukas showed that there was a similar trend across the different registries, and no significant heterogeneity among data sources.
The meta-analysis showed an overall increased risk of herpes zoster infection up to 75% in patients whose inflammatory rheumatic diseases were treated with anti-TNF inhibitors. Overall, the pooled odds ratio for herpes zoster infection with anti-TNF therapy was 1.75 (95% confidence interval, 1.50-2.04). This was almost a twofold risk of developing disease with these drugs compared with DMARDs, Dr. Lukas said at the annual European Congress of Rheumatology.
Odds ratios by national registries were BIOBADASER, 2.45; BSRBR, 1.45; CORRONA, 2.34; McDonald, 1.33; and RABBIT, 1.82.
In addition to the meta-analysis, investigators used data from three registries specifically to determine whether the use of any particular anti-TNF drug was associated with a higher risk. "We found that one registry showed [that] infliximab had a somewhat higher risk, but this was only one out of three studies. The other two studies showed a similar risk across all anti-TNF agents."
In the McDonald registry, the risk was found to e higher with infliximab (OR, 1.32; 95% CI, 0.85-2.03) compared with etanercept (OR, 0.62; 95% CI, 0.40-0.95) and adalimumab (OR 0.53; 95% CI, 0.31-0.91).
"We already knew that these patients were prone to herpes zoster; we see the lesions in clinics." But there are preventive measures available that one can take, he said.
In the United States, there are vaccines to prevent herpes zoster, which are available to people who are older than age 60 years, or are at high specific risk of developing herpes zoster infection. "In these patients, we could think about vaccines before treatment is started," pointed out Dr. Lukas. "It is a live vaccine so it should be given a month before start of anti-TNF therapy. In Europe, where the vaccine is unavailable, we need to give patients prophylaxis."
Dr. Lukas reported no relevant conflicts of interest. The study was supported by an unrestricted educational grant from Abbott France.