Anti-TNF therapy is associated with an increased risk of serious infections in patients with rheumatoid arthritis especially in the first 6 months of treatment: updated results from the British Society for Rheumatology Biologics Register with special emphasis on risks in the elderly.
OBJECTIVE
To evaluate the risk of serious infections (SIs) in patients with RA treated with anti-TNF therapy with emphasis on the risk across different ages.


METHODS
Using data from the British Society for Rheumatology Biologics Register, a prospective observational study, we compared the risk of SI between 11 798 anti-TNF-treated patients and 3598 non-biologic DMARD (nbDMARD)-treated patients.


RESULTS
A total of 1808 patients had at least one SI (anti-TNF: 1512; nbDMARD: 296). Incidence rates were: anti-TNF 42/1000 patient-years of follow-up (95% CI 40, 44) and nbDMARD 32/1000 patient-years of follow-up (95% CI 28, 36). The adjusted hazard ratio (adjHR) for SI in the anti-TNF cohort was 1.2 (95% CI 1.1, 1.5). The risk did not differ significantly between the three agents adalimumab, etanercept and infliximab. The risk was highest during the first 6 months of therapy [adjHR 1.8 (95% CI 1.3, 2.6)]. Although increasing age was an independent risk factor for SI in both cohorts, there was no difference in relative risk of infection in patients on anti-TNF therapy in the older population. There was no difference in hospital stay for SI between cohorts. Mortality within 30 days of SI was 50% lower in the anti-TNF cohort [odds ratio 0.5 (95% CI 0.3, 0.8)].


CONCLUSIONS
These data add to currently available evidence suggesting that anti-TNF therapy is associated with a small but significant overall risk of SI. This must be balanced against the risks associated with poor disease control or alternative treatments.
Galloway
James B
JB
Arthritis Research UK Epidemiology Unit, The University of Manchester, Department of Infectious Diseases, North Manchester General Hospital, Stopford Building, Oxford Road, Manchester M13 9PT, UK.
Hyrich
Kimme L
KL
Mercer
Louise K
LK
Dixon
William G
WG
Fu
Bo
B
Ustianowski
Andrew P
AP
Watson
Kath D
KD
Lunt
Mark
M
Symmons
Deborah P M
DP
D000368:Aged; D000911:Antibodies, Monoclonal / Q000009:adverse effects; D018501:Antirheumatic Agents / Q000009:adverse effects*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy*; D005260:Female; D006801:Humans; D007239:Infections / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D012042:Registries; D012044:Regression Analysis; D012307:Risk Factors; D000079424:Tumor Necrosis Factor Inhibitors; D048069:Tumor Necrosis Factors / Q000009:adverse effects; D006113:United Kingdom
D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D000079424:Tumor Necrosis Factor Inhibitors; D048069:Tumor Necrosis Factors