Does diabetes mellitus comorbidity increase the risk of drug-induced liver injury during tuberculosis treatment?

BACKGROUND: The growing burden of diabetes worldwide is a threat to tuberculosis (TB) control. Drug-induced liver injury (DILI) due to TB drugs is a significant concern and there is currently limited evidence on the effect of diabetes on TB DILI. This study sought to investigate the effect of diabetes as a risk factor for DILI and to further study any potential co-factors. METHODS: An unmatched case-control study. Cases were TB patients on 2RHZE/4RH presenting with DILI from 2013–2017 in Porto Alegre, Brazil. Controls were contemporaneous TB patients without DILI being treated in any one of the same five Porto Alegre TB clinics. The exposure variables were diabetes (main exposure variable), age, sex, alcohol misuse, human immunodeficiency virus (HIV), hepatitis C (HCV) and B (HBV) viruses, concomitant hepatotoxic drugs, other liver diseases and TB site. The outcome variable was the occurrence of DILI. RESULTS: Odds of DILI were increased by: older age group 51–60, 61–70 and 71–93 years (adjusted OR 2.39, 95%CI 1.30–4,38; adjusted OR 4.37, 2.28–8,35; adjusted OR 12.91, 5.81–28,66, respectively), HIV positive status (adjusted OR 3.59, 95%CI 2.25–5.73), HCV positive status (adjusted OR 3.49, 95%CI 1.96–6.21) and having concurrent pulmonary and extrapulmonary TB (adjusted OR 3.16, 95%CI 1.93–5.19). Diabetes, gender, and other hepatotoxic drugs were not associated with DILI. CONCLUSIONS: This study confirms the association between TB DILI and well-known risk factors but did not demonstrate increased odds of TB DILI in patients with diabetes.