학술논문

Quantifying gaps in the tuberculosis care cascade in Brazil: A mathematical model study using national program data.
Document Type
Article
Source
PLoS Medicine. 3/21/2024, Vol. 21 Issue 3, p1-16. 16p.
Subject
*DELAYED diagnosis
*HIV
*TUBERCULOSIS
*DRUG abuse treatment
*MATHEMATICAL models
*DIAGNOSTIC errors
Language
ISSN
1549-1277
Abstract
Background: In Brazil, many individuals with tuberculosis (TB) do not receive appropriate care due to delayed or missed diagnosis, ineffective treatment regimens, or loss-to-follow-up. This study aimed to estimate the health losses and TB program costs attributable to each gap in the care cascade for TB disease in Brazil. Methods and findings: We constructed a Markov model simulating the TB care cascade and lifetime health outcomes (e.g., death, cure, postinfectious sequelae) for individuals developing TB disease in Brazil. We stratified the model by age, human immunodeficiency virus (HIV) status, drug resistance, state of residence, and disease severity, and developed a parallel model for individuals without TB that receive a false-positive TB diagnosis. Models were fit to data (adult and pediatric) from Brazil's Notifiable Diseases Information System (SINAN) and Mortality Information System (SIM) for 2018. Using these models, we assessed current program performance and simulated hypothetical scenarios that eliminated specific gaps in the care cascade, in order to quantify incremental health losses and TB diagnosis and treatment costs along the care cascade. TB-attributable disability-adjusted life years (DALYs) were calculated by comparing changes in survival and nonfatal disability to a no-TB counterfactual scenario. We estimated that 90.0% (95% uncertainty interval [UI]: 85.2–93.4) of individuals with TB disease initiated treatment and 10.0% (95% UI: 7.6 to 12.5) died with TB. The average number of TB-attributable DALYs per incident TB case varied across Brazil, ranging from 2.9 (95% UI: 2.3 to 3.6) DALYs in Acre to 4.0 (95% UI: 3.3 to 4.7) DALYs in Rio Grande do Sul (national average 3.5 [95% UI: 2.8 to 4.1]). Delayed diagnosis contributed the largest health losses along the care cascade, followed by post-TB sequelae and loss to follow up from TB treatment, with TB DALYs reduced by 71% (95% UI: 65 to 76), 41% (95% UI: 36 to 49), and 10% (95% UI: 7 to 16), respectively, when these factors were eliminated. Total health system costs were largely unaffected by improvements in the care cascade, with elimination of treatment failure reducing attributable costs by 3.1% (95% UI: 1.5 to 5.4). TB diagnosis and treatment of false-positive individuals accounted for 10.2% (95% UI: 3.9 to 21.7) of total programmatic costs but contributed minimally to health losses. Several assumptions were required to interpret programmatic data for the analysis, and we were unable to estimate the contribution of social factors on care cascade outcomes. Conclusions: In this study, we observed that delays to diagnosis, post-disease sequelae and treatment loss to follow-up were primary contributors to the TB burden of disease in Brazil. Reducing delays to diagnosis, improving healthcare after TB cure, and reducing treatment loss to follow-up should be prioritized to improve the burden of TB disease in Brazil. Using a mathematical model, Sivaram Emani and colleagues quantify the gaps in the tuberculosis care cascade in Brazil. Author summary: Why was this study done?: In Brazil, many people with tuberculosis (TB) do not receive proper care due to delayed diagnosis, ineffective treatment, or loss to follow-up. Care cascade analysis can be used to understand the TB burden of disease, providing insights for policy generation and public health strategy. What did the researchers do and find?: We used a care cascade model to estimate the health losses and TB program costs attributable to each gap in the care cascade for TB disease in Brazil. We found that delayed diagnosis, post-TB health sequelae, and loss to follow-up were the main contributors to TB disease burden. What do these findings mean?: Our findings underscore the potential benefit of reducing delays in diagnosis, improving health outcomes after TB cure, and enhancing retention in TB treatment to alleviate the burden of TB disease in Brazil. This study did not consider social factors, although these are known to be important determinants of TB disease outcomes. [ABSTRACT FROM AUTHOR]