Background Since the introduction of biologics many concerns about the increased risk of infections, have been reported Available data from randomized controlled trials, national registries and open label studies do not fully clarify the magnitude of this risk . To date, the real impact of infections in the daily practice in the rheumatologic centers is still largely unknown.
Objectives To evaluate the infection rates associated with the use of biologics in a large cohort of patients enrolled in 3 tertiary referral rheumatologic units in Italy. In addition, the risk of infections, including serious infections, was correlated with different clinical features.
Methods A retrospective study, between January 2010 and December 2013, enrolled 731 rheumatic patients: 332 with rheumatoid arthritis (RA), 308 with psoriatic arthritis (PsA), 85 with ankylosing spondylitis (AS), 16 with primary Sjogren syndrome (pSS). Demographic and disease characteristics, therapies, comorbidities and infectious events were recorded and statistically analysed by multivariate analysis.
Results All patients received at least 1 biologic, 82 patients 2 biologics, 30 patients 3 biologics, 6 patients 4 biologics and 4 patients 5 biologics. Two-hundred-thirty-five infectious episodes were observed in 208 (28.4%) patients. About total infections, bacteria were identified in 70.6% out of total cases, and viruses in 18.3%. The most common site of infection was the urinary tract (39.1%). Duration of disease (p=0.02), longer follow-up (p=0.0001), concomitant steroid therapy (p=0.001), comorbidities (p=0.015), treatment with infliximab (p=0.001), etanercept (p=0.029), golimumab, (p=0.004), abatacept (p=0.0001) and tocilizumab (p=0.0001) were significantly associated with any infection. In our cohort, 17 episodes fulfilled the criteria of serious infection, and occurred in 17 different patients (2.3%), the majority involving the lower respiratory tract (41.2%). Serious infections were associated with the beginning of biologics in older age (p=0.002), the use of i.v. therapy with infliximab (p=0.02), rituximab (p=0.05) and tocilizumab (p=0.01).
Conclusions Surprisingly, our study shows that, in daily practice, a lower rate of infections was observed in our patients, when compared with previous reports. Duration of disease, concomitant steroid therapy and comorbidities may be considered risk factors for the occurrence of infections in treated patients. Of note, serious infections seem to be associated with older age of patients and i.v. treatments.
Singh JA. Adverse effects of biologics: a network meta-analysis and Cochrane overview. Cochrane Database Syst Rev. 2011 Feb 16;(2):CD008794.
Ruderman EM. Overview of safety of non-biologic and biologic DMARDs. Rheumatology (Oxford). 2012;51:vi37–43.
Disclosure of Interest None declared