For patients on ART at the start of TB treatment, a multivariable analysis using Cox proportional hazard models showed a higher risk of TB mortality associated with increasing age (Adjusted hazard ratio (aHR) 1.28 per 10 years increase of age, 95% CI: 1.17–1.40, p < 0.001) and a lower risk of TB mortality associated with new TB (aHR 0.71, 95% CI: 0.61–0.84, p < 0.001) and increasing CD4 counts (aHR 0.87 per increase of 50 cells/mm3, 95% CI: 0.84–0.89, p < 0.001). The gene discussed is CD4; the disease is tuberculosis.