Diagnosis delay and pre-diagnosis catastrophic costs in newly diagnosed adults with tuberculosis in Cambodia: a cross-sectional study

Evidence on the link between catastrophic costs and tuberculosis (TB) diagnosis delay is limited, particularly in Southeast Asia. This study estimates the prevalence of pre-diagnosis catastrophic costs and examines its association with TB diagnosis delay among adults newly diagnosed with TB through active case-finding programs in Cambodia. This cross-sectional study used baseline data from a TB cohort collected between March and September 2022. Participants were aged ≥ 18 years and had been diagnosed with TB within one month before recruitment. A total of 711 individuals from 10 operational districts were recruited. Pre-diagnosis catastrophic costs were defined as total TB-related costs incurred before TB diagnosis amounting to ≥ 10% of the annual household income. We defined diagnosis delay as the time from the onset of TB symptoms to the date of diagnosis. Multivariable logistic regression was performed among participants who reported using health services for TB symptoms before diagnosis to assess associations between catastrophic costs, diagnosis delay, and other factors. The estimated prevalence of pre-diagnosis catastrophic costs at the 10% threshold was 8.6% (95% CI: 6.6%–11.1%) among the 711 participants. The median diagnosis delay was 64 days (range: 1–365). Direct medical costs accounted for 80.6% of total pre-diagnosis costs. Among participants who sought healthcare before diagnosis, median out-of-pocket costs were highest for private health practitioners (USD 90, IQR: 31–200), followed by pharmacies (USD 30, IQR: 13.88–83). Among those who sought care before TB diagnosis ( n = 256), a diagnosis delay of ≥ 64 days was significantly associated with higher odds of experiencing pre-diagnosis catastrophic costs (pooled adjusted odds ratio [aOR] = 2.87, 95% CI: 1.42–5.80). Approximately one in ten individuals with TB incurred pre-diagnosis catastrophic costs, and longer diagnosis delays were associated with higher odds of pre-diagnosis catastrophic costs. These findings underscore the need to strengthen TB awareness, particularly among financially vulnerable populations, and improve access to timely TB diagnostic services in public health facilities.