Incidence of tuberculosis in patients receiving anti-TNF therapy for rheumatic diseases: a systematic review

Introduction The TNF inhibitors were the first immunobiologicals used to treat rheumatic diseases, but their use is associated with an increased risk of tuberculosis. The primary objective is to estimate the incidence of tuberculosis in patients with rheumatic diseases exposed to anti-TNF therapy. The secondary objectives are to evaluate the incidence of tuberculosis by region and subgroups of diseases, to review the presentation of tuberculosis in these patients, and to assess the time elapsed between onset of anti-TNF therapy and development of active granulomatous disease. Methods A systematic review of the literature was conducted in MEDLINE, the Cochrane Library, and LILACS. The primary endpoint was described as incidence and secondary outcomes, through subgroup analyses and comparisons of means. Results We included 52 observational studies. Among the exposed patients, 947 cases of tuberculosis were documented (62.2% pulmonary), with a cumulative incidence of 9.62 cases per 1000 patients exposed. TB incidence across different continents was distributed as follows: South America, 11.75 cases/1000 patients exposed; North America, 4.34 cases/1000 patients exposed; Europe, 6.28 cases/1000 patients exposed; and Asia, 13.47 cases/1000 patients exposed. There were no significant differences in TB incidence among the described diseases. The mean time elapsed from start of anti-TNF therapy until the endpoint was 18.05 months. Conclusion The incidence of TB in patients with rheumatic diseases exposed TNF inhibitor considering all countries was 9.62 cases per 1000 patients exposed. TB incidence was higher in South America and Asia compared with North America and Europe. Most cases occurred in the first XX months of use, and the pulmonary form predominated.