Prevalence of latent tuberculosis infection in patients with rheumatoid arthritis and its relationship with sociodemographic and clinical characteristics

Objective: The aim of this study was to determine the prevalence of latent tuberculosis infection (LTBI) and their relationship with sociodemographic and clinical characteristics in patients with rheumatoid arthritis (RA). Methodology: An analytical cross-sectional study was carried out, with a non-probabilistic sample of 538 patients followed in a Colombian rheumatology center specialized in RA. Patients were tested using tuberculin skin test (TST). Thresholds of this test were defined according to CDC recommendations. We stratified the analysis by sex, type of treatment (conventional and biological therapy) and negative and positive latent tuberculosis infection (LTBI). Results: A prevalence of positive TST of 12.1% (65/538; 95%CI 9.6%-15.1%) in Colombian patients with RA was estimated. We found a prevalence of 14.8% (12/81; 95%CI 8.7%-24.1%) in men, and 11.6% (53/457; 95%CI 9.0%-14.9%) in women. Patient ages ranged from 19 to 92 years (mean, 57 years; SD, 12.0), the female-to-male ratio was 5.6:1, and median time since diagnosis of RA was 15 years (IQR, 8.8 17.8). The prevalence of LTBI was not significantly associated with sociodemographic and another clinical characteristic, except for time since diagnosis of RA (p = 0.048). However, the prevalence was significantly higher in the csDMARD group (16%) compared to the bDMARD group (9.3%) (p = 0.023). Subgroup analyses according to the type of biologic therapy (anti-TNF, non-TNF biologics, and JAK inhibitors), showed no significant associations with LTBI. Conclusions: This study is one of the first approaches in Colombia to estimate the prevalence of LTBI in patients with rheumatoid arthritis. The prevalence of LTBI was associated with time since diagnosis of RA and type of therapy