Patient-related diagnostic delay and risk of unfavorable treatment outcomes among pulmonary tuberculosis patients at the antituberculosis center of Brazzaville, Republic of Congo

Tuberculosis (TB) remains a major public health concern worldwide. Early diagnosis is crucial to reduce TB transmission and improve treatment outcomes. This study assessed patient-related diagnostic delay and their impact on the treatment outcomes among pulmonary tuberculosis patients (PTB) at the Antituberculosis center in Brazzaville. We conducted a prospective cohort study from July 2023 to August 2024. Sociodemographic, clinical characteristics, patient-related diagnostic delays delay (short ≤ 30 days, prolonged > 30 days), and treatment outcomes were recorded. Logistic regression models were used to identify risk factors, reporting crude and adjusted odds ratios (OR, AOR) with 95% confidence intervals (CI). A p-value 30 days had higher odds of death (OR = 2.30, 95%CI: 0.7-7.3) and treatment failure (OR = 5.4, 95%CI: 0.8-66.4). A high median patient-related diagnostic delay of 30 days was observed in Brazzaville. Residence in peripheral districts and diabetes mellitus status were significant predictors of delay. Although not statistically significant, prolonged patient delays tended to be associated with higher risks of death and treatment failure. Strengthening early case detection and promoting prompt healthcare-seeking and diagnosis among symptomatic individuals are critical for reducing TB diagnostic delays and improving treatment outcomes.