Predictors for treatment outcomes among patients with drug-susceptible tuberculosis in the Netherlands: a retrospective cohort study

Objectives We evaluated treatment outcomes and predictors for poor treatment outcomes for tuberculosis (TB) among native- and foreign-born patients with drug-susceptible TB (DSTB) in the Netherlands. Methods This retrospective cohort study included adult patients with DSTB treated from 2005 to 2015 from a nationwide exhaustive registry. Predictors for unsuccessful treatment outcomes (default and failure) and TB-associated mortality were analysed using multivariate logistic regression. Results Among 5674 identified cases, the cumulative incidence of unsuccessful treatment and mortality were 2.6% (n/N = 146/5674) and 2.0% (112/5674), respectively. Although most patients were foreign-born (71%; 4042/5674), no significant differences in these outcomes were observed between native- and foreign-born patients (p > 0.05). Significant predictors for unsuccessful treatment were aged 18-24 years (odds ratio (OR), 2.04; 95% CI 1.34-3.10), homelessness (OR, 2.56; 95% CI 1.16-5.63), prisoner status (OR, 5.39; 95% CI 2.90-10.05) and diabetes (OR, 2.02; 95% CI 1.03-3.97). Furthermore, predictors for mortality were aged 74-84 years (OR, 5.58; 95% CI 3.10-10.03) or ≥85 years (OR, 9.35, 95% CI 4.31-20.30), combined pulmonary and extra-pulmonary TB (OR, 4.97; 95% CI 1.42-17.41), central nervous system (OR, 120, 95% CI 34.43-418.54) or miliary TB (OR, 10.73, 95% CI 2.50-46.02), drug addiction (OR, 3.56; 95% CI 1.34-9.47) and renal insufficiency/dialysis (OR, 3.23; 95% CI 1.17-8.96). Conclusions Native- and foreign-born patients exhibited similar TB treatment outcomes. To further reduce disease transmission and inhibit drug resistance, special attention should be given to high-risk patients.