After adjusting for sex, age, BMI, CKD, chronic liver disease, diabetes, hypertension, AIDS, etiology of tuberculosis, anti-tuberculosis therapy, retreated TB, drug resistant TB, fever, ALT, AST, PaO2/FiO2 ratio, procalcitonin, C-reactive protein, mechanical ventilation use, renal replacement therapy, and multilobar pulmonary infiltrates, we observed a non-linear relationship between BAR and 28-day all-cause through a restricted cubic spline (P for non-linearity < 0.001, Fig. 4). Here, CRP is linked to tuberculosis.