Adherence to preventive treatment for latent tuberculosis infection in close contacts of pulmonary tuberculosis patients: A cluster-randomized controlled trial in China

Objectives

This study examined adherence rates to tuberculosis preventive treatment (TPT) among close contacts of individuals with pulmonary tuberculosis (PTB) and identified factors associated with TPT adherence in China.

Methods

A multicenter, cluster-randomized, open-label control trial was carried out across three sites involving 34 counties in China. Close contacts of bacteriologically confirmed rifampin and isoniazid-susceptible PTB cases were identified and screened for latent tuberculosis infection (LTBI). Eligible participants were randomly assigned to either the 3H₂P₂ group, which consisted of a 3-month, twice-weekly regimen of rifapentine and isoniazid, or the 6H group, which entailed a 6-month daily regimen of isoniazid. To assess the factors influencing adherence, a two-level logistic regression model was utilized.

Results

Out of the 2434 close contacts who initiated TPT, 2121 (87.1%) completed the regimen. Of the 313 individuals who did not complete TPT, 60.1% refused to continue, and 27.8% discontinued due to adverse effects. The two-level logistic regression model revealed several factors associated with enhanced TPT adherence: enrollment in the 3H₂P₂ group (odds ratio [OR] = 2.09), management by a TB dispensary responsible for TPT (OR = 2.55), supervision by healthcare workers (OR = 6.40), and clinician incentives (OR = 2.49). Conversely, the occurrence of any adverse effects (OR = 0.08) was identified as a risk factor for nonadherence.

Conclusion

Administering TPT to individuals with LTBI is feasible among close contacts. Adherence to TPT can be enhanced through shorter, safer treatment regimens and supportive interventions, such as directly supervised therapy for TPT recipients and incentives for healthcare providers managing TPT.