Mortality and associated factors among drug-resistant tuberculosis patients in Portugal, 2000-2016

Treatment of drug-resistant tuberculosis (TB) has become a major challenge for TB control worldwide and treatment outcomes are often suboptimal. Overall, the death rate reported by WHO was 15% among patients with multidrug-resistant tuberculosis (MDR-TB) and 26% among patients with extensively drug-resistant tuberculosis (XDR-TB). We aimed to evaluate treatment outcomes and to identify the factors associated with death among MDR- and XDR-TB patients. We studied all patients that started MDR/XD-TB treatment in Portugal from 2000 to 2016 (follow up December 2019). Logistic regressions were used to identify the factors associated with treatment outcomes. We assessed treatment outcomes of 294 MDR- and 142 XDR-TB patients. Among MDR-TB patients, the death rate was 18%. Injectable drugs use (OR 6.70; 95% CI 3.12–14.40) and comorbidities (OR 2.53; 95% CI 1.09–5.88) were the identified risk factors. Fourteen (26 %) patients died in the first 3 months of treatment, 36% of which were HIV-positive injecting drug users. Among XDR-TB patients, the death rate was 24%. Incarceration (OR 3.30; 95% CI 1.10–9.87) was the risk factor associated with death. Twelve (75%) prisoners were also injecting drug users. Three (9%) patients died in the first 3 months of treatment. Taking into account the identified risk factors associated with death, we need to readjust measures to enable earlier diagnosis and improve case management on specific population groups.