Tuberculosis risk with biologics by screening-guided preventive strategy in rheumatoid arthritis under intermediate tuberculosis burden.

OBJECTIVES

We aimed to compare tuberculosis (TB) risk during biologics treatment between patients with RA who did (prophylaxis) and did not (non-prophylaxis) undergo chemoprophylaxis following pre-biologic latent TB screening in Korea of an intermediate TB burden.

METHODS

Using the 2002-16 Korea National Health Insurance database, we conducted a cohort study examining TB risk, defined by International Classification of Diseases Tenth Revision codes plus anti-TB drugs, among RA patients initiating a biologic drug with and without chemoprophylaxis after screening triage for latent TB. To control baseline confounding, we used propensity score-based fine stratification (PSS) and weighting. Cox proportional hazards models estimated hazard ratios and 95% CIs comparing TB risk between the prophylaxis vs non-prophylaxis groups.

RESULTS

The PSS-weighted study cohort (mean age 57.0 years; 81.3% female) included 2249 and 7225 RA patients in the prophylaxis and non-prophylaxis groups, respectively. During 2.42 years of biologics treatment, 118 patients developed TB with the incidence rate per 100 person-years of 0.33 in the prophylaxis and 0.63 in the non-prophylaxis groups. The PSS-weighted hazard ratio (95% CI) for TB associated with the prophylaxis was 0.52 (0.32, 0.86). During the follow-up time, the incidence rate of TB remained consistently low in the prophylaxis group but it was highest in the first year, then time-dependently declined in the non-prophylaxis group.

CONCLUSION

This population-based cohort study warns that the current screening-based preventive strategy generates a substantially higher TB risk after biologics initiation among screening-negative patients compared with screening-positive patients receiving chemoprophylaxis, when the background TB burden is not low.