Catastrophic costs due to tuberculosis worsen treatment outcomes: a prospective cohort study in Indonesia

BACKGROUND: While the incidence of catastrophic costs due to tuberculosis (TB) remains high, there is little evidence about their impact on TB treatment outcomes and adherence. We assessed their effect on treatment outcomes and adherence in Indonesia. METHODS: We interviewed 282 adult TB patients who underwent TB treatment in urban, suburban and rural districts of Indonesia. One year after the interview, we followed up treatment adherence and outcomes. We applied multivariable analysis using generalized linear mixed models. RESULTS: Follow-up was complete for 252/282 patients. Eighteen (7%) patients had unsuccessful treatment and 40 (16%) had poor adherence. At a threshold of 30% of annual household income, catastrophic costs negatively impacted treatment outcomes (adjusted odds ratio [aOR] 4.15 [95% confidence interval {CI} 1.15 to 15.01]). At other thresholds, the associations showed a similar pattern but were not statistically significant. The association between catastrophic costs and treatment adherence is complex because of reverse causation. After adjustment, catastrophic costs negatively affected treatment adherence at the 10% and 15% thresholds (aOR 2.11 [95% CI 0.97 to 4.59], p = 0.059 and aOR 2.06 [95% CI 0.95 to 4.46], p = 0.07). There was no evidence of such an effect at other thresholds. CONCLUSIONS: Catastrophic costs negatively affect TB treatment outcomes and treatment adherence. To eliminate TB, it is essential to mitigate catastrophic costs.