Title : Risk of tuberculosis in patients with autoimmune diseases treated with biologic therapies: A retrospective cohort study in Colombia
Abstract:
Background: Tuberculosis is a recognized complication associated with the use of biologic therapies for the treatment of autoimmune diseases. The risk of tuberculosis among treated patients may be further increased in tuberculosis-endemic settings such as Colombia.
Objective: To determine the cumulative incidence of tuberculosis in Colombian patients with autoimmune diseases receiving biologic therapy and diagnosed with latent tuberculosis infection, and to identify associated risk factors for progression to active disease.
Methods: We conducted a retrospective cohort study including adult patients with autoimmune diseases and latent tuberculosis infection managed within a private healthcare network between January 2003 and December 2024. Follow- up extended from biologic therapy initiation until completion of tuberculosis preventive treatment or diagnosis of active tuberculosis.
Results: A total of 492 patients were included (mean age 49.1 ± 15.9 years; 56.1% female), with a median follow-up of 28.8 months (interquartile range 9.4–51.7 months). The most prevalent autoimmune conditions were rheumatoid arthritis (64.0%), psoriasis (12.2%), atopic dermatitis (7.1%), and spondyloarthritis (5.3%). Most patients initiated biologic therapy before starting tuberculosis preventive treatment (81.1%) and received integrated healthcare follow-up (68.1%). The main biologic agents administered included anti–tumor necrosis factor alpha antibodies (45.7%), anti-CD20 therapies (30.1%), and integrin inhibitors (18.7%). Preventive treatment consisted predominantly of isoniazid monotherapy (93.5%). Seven cases of active tuberculosis were identi^ied (1.42%), corresponding to an incidence rate of 3.8 per 10,000 person-months (95% con^idence interval [CI] 1.5–7.8). Most cases occurred in women (85.7%), were associated with radiographic ^indings suggestive of prior tuberculosis, occurred in patients without integrated follow- up, and were treated with isoniazid-based preventive therapy. Initiation of biologic therapy 12 months or more after autoimmune disease diagnosis was identi^ied as a signi^icant risk factor for tuberculosis (odds ratio 6.2; 95% CI 1.3–28.2).
Conclusions: Although the absolute incidence of tuberculosis was low, it remained higher than that of the general population. Risk was concentrated among patients exposed to TNF-α inhibitors, those with greater immunosuppressive burden, and those with gaps in the implementation of the preventive cascade. Delayed initiation of biologic therapy was independently associated with progression to active tuberculosis.
