Background:
In March 2010, the Brazilian Ministry of Health updated its tuberculosis (TB) treatment guidelines, changing the standard intensive phase regimen from three drugs (rifampicin, isoniazid, and pyrazinamide – RHZ) to a four-drug fixed-dose combination (rifampicin, isoniazid, pyrazinamide, and ethambutol – RHEZ-FDC). This change aimed to curb increasing primary isoniazid resistance and simplify drug dispensing. However, the addition of ethambutol to an already complex therapeutic scheme raised concerns regarding the potential increase in adverse drug reactions (ADRs).
Abstract:
Methods: A retrospective cohort study was conducted using data from 730 randomly selected TB patients (365 per group) treated at a reference center in Salvador, Brazil, between 2007 and 2014. The study compared the frequency of ADRs and cure rates between the RHZ (pre-2010) and RHEZ-FDC (post-2010) regimens.
Results: Patients treated with the RHEZ regimen developed ADRs significantly more often than those on the RHZ regimen (23.6% vs. 15.1%; $p = 0.01$). Multivariable analysis confirmed that the RHEZ-FDC scheme was independently associated with a 1.61-fold increased risk of ADRs. This risk was particularly pronounced in patients older than 30 years ($p = 0.01$). The most common ADRs were gastrointestinal and neurological. Cure rates were similar between both treatment groups.
Conclusion: The implementation of the four-drug RHEZ-FDC regimen in Brazil increased the incidence of adverse drug reactions without significantly altering cure rates. These findings highlight the need for careful clinical monitoring, especially for patients over 30 years of age.
Keywords: Tuberculosis; adverse drug reactions; ethambutol; fixed-dose combination; treatment outcome; Brazil.
Clique aqui
- Data de Publicação: 26/12/2019
- Autores: Marı ́a B. ArriagaID1,2,3,4*, Ninfa M. C. TorresID1,5, Nelia C. N. Araujo1,2, Simone C. C. Caldas2 , Bruno B. AndradeID2,3,4,6,7,8*, Eduardo M. Netto1,2
