AUTHOR=Ortiz Laza N. , Lopez Aranaga I. , Toral Andres J. , Toja Uriarte B. , Santos Zorrozua B. , Altube Urrengoechea L. , Garros Garay J. , Tabernero Huguet E. 

TITLE=Latent tuberculosis infection treatment completion in Biscay: differences between regimens and monitoring approaches

JOURNAL=Frontiers in Medicine

VOLUME=Volume 10 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2023.1265057

DOI=10.3389/fmed.2023.1265057

ISSN=2296-858X

ABSTRACT=Contact tracing and treatment of latent tuberculosis infection (LTBI) is a key element of tuberculosis (TB) control in low TB incidence countries. A TB control and prevention program has been active in the Basque Country since 2003, including the development of the nurse case manager role and a unified electronic record. Three World Health Organization-approved LTBI regimens have been used: isoniazid for 6 months (6H), rifampicin for 4 months (4R), and isoniazid and rifampicin for 3 months (3HR). Centralized follow-up by a TB nurse case manager started in January 2016, with regular telephone follow-up, telemonitoring of blood test results, and monitoring of adherence by electronic review of drugs dispensed in pharmacies.
Objective: To estimate LTBI treatment completion and toxicity of different preventive treatment regimens in a real-world setting. Secondary objective: to investigate the adherence to different approaches to preventive treatment monitoring
Methods: 
A multicentre retrospective cohort study was conducted using data collected prospectively on contacts of patients with TB in five hospitals in Biscay from 2003 to 2022.
Results
A total of 3066 contacts with LTBI were included. The overall completion rate was 66.8%; 86.5% of patients on 3HR (n=699) completed treatment vs 68.3% (n=1260) of those on 6H (p<0.0001). The rate of toxicity was 3.8%, without significant differences between the regimens. 
A total of 394 contacts were monitored by a TB nurse case manager. In these patients, the completion rate was 85% vs 67% in those under standard care (p<0.001). A multivariate logistic regression model identified three independent factors associated with treatment completion: being female, the 3HR regimen, and nurse telemonitoring.  
Conclusions
3HR was well tolerated and associated with a higher rate of treatment completion.
Patients with nurse telemonitoring follow-up had better completion rates.