Southern Africa study finds TB treatment outcomes miss WHO targets

Tuberculosis (TB) remains a major public health challenge in many parts of the world, and outcomes after treatment are still worse than health authorities would like, especially where HIV and drug-resistant forms of TB are common. Lukas Fenner is the corresponding author of a multi-country analysis that aimed to identify which patients are most at risk of unsuccessful TB treatment so care can be improved. The research team used patient data from five clinical cohorts in Southern Africa that are part of broader research networks: the International epidemiology database to evaluate AIDS (IeDEA) and clinics including the Center for Infectious Disease Research, Zambia; Chiure health center, Mozambique; Martin Preuss Center, Lighthouse clinic, Malawi; Masvingo health center, Zimbabwe; and Themba Lethu clinic, Hellen Joseph hospital, South Africa. The study included all people aged 15 years or older who started TB treatment at these sites and looked across basic social and clinical information to find patterns linked to poor outcomes. The stated goal was practical: spot predictors of unsuccessful treatment so programs can reduce deaths, losses to follow-up, and treatment failures.

To find those predictors the researchers assessed treatment outcomes and their relationship with patient characteristics using multivariable mixed-effects models, a statistical method that accounts for differences between clinics and countries. The team defined “unsuccessful outcomes” as death, loss to follow-up, and treatment failure, and then tested how sociodemographic and clinical factors were associated with those results. The analysis reported specific associations: one factor showed an adjusted odds ratio (aOR) of 0.6 (95%-CI 0.36-0.99). Importantly, multidrug-resistant TB (MDR-TB) was associated with an increased risk of unsuccessful outcomes (aOR 2.4, 95%-CI 1.17-4.97). Education appeared protective against loss to follow-up: primary education was linked to a reduced risk (aOR 0.3, 95%-CI 0.14-0.89) and secondary or higher education showed a similar reduction (aOR 0.3, 95%-CI 0.11-0.67). Overall, the outcomes observed in these cohorts did not meet the World Health Organization target of less than 10% unsuccessful outcomes.

The findings point to clear priorities for TB programs in high-burden settings. First, MDR-TB patients are at substantially higher risk of poor outcomes and need focused efforts to prevent treatment interruption and death. Second, loss to follow-up is a major driver of unsuccessful outcomes; the protective association with education suggests barriers such as information, access, or social support may play a role. The authors emphasize the need for stronger retention activities—actions to keep people engaged in care—and better diagnostic capacity so MDR-TB is identified early and treated appropriately. Because the cohorts spanned several Southern African countries, the results give a regional picture that policy makers and clinic managers can use to target resources. In short, meeting WHO targets will require improving how patients are followed and treated, with particular attention to drug-resistant TB and the social factors that lead people to drop out of care.