Drug-resistant tuberculosis in Lishui, China: first-line drug resistance patterns, trends, and risk factors from a 10-year retrospective study (2015-2024).

PURPOSE: Despite ongoing global efforts, drug-resistant TB (DR-TB) continues to pose a substantial threat to public health, and systematic longitudinal surveillance data on local resistance patterns are lacking in many regions. This study analyzed first-line drug resistance patterns and annual trends in Lishui, China from 2015 to 2024 and identified independent risk factors for multidrug-resistant tuberculosis (MDR-TB).

METHODS

A total of 2,339 TB patients with available phenotypic drug susceptibility testing (pDST) results from the designated TB treatment institution in Lishui were retrospectively enrolled between January 2015 and December 2024. Annual drug resistance trends were assessed, and independent risk factors for MDR-TB were evaluated through multivariate logistic regression.

RESULTS

The overall prevalence of DR-TB and MDR-TB was 20.09 and 6.93%, respectively. Over the 10-year period, overall DR-TB prevalence declined from 23.50% in 2015 to 15.63% in 2024 (APC: -1.30%, p = 0.661), with this reduction largely attributable to the declining trend among retreated patients (56.25-15.00%, APC: -8.19%, p = 0.156), while resistance rates in new patients remained broadly stable (APC: +0.95%, p = 0.732). MDR-TB prevalence in retreated patients decreased significantly from 40.63 to 15.00% (Cochran-Armitage trend test, p = 0.008). Prior TB treatment history (AOR = 4.345, 95% CI: 3.029-6.234, p < 0.001) and farmer occupation (AOR = 1.638, 95% CI: 1.047-2.562, p = 0.031) were identified as independent risk factors for MDR-TB.

CONCLUSION

The decrease in drug resistance among retreated patients was the main driver of the overall decline in DR-TB prevalence observed in Lishui across the study period. The relative stability of resistance in new patients suggests ongoing circulation of drug-resistant strains in the community, highlighting the need for expanded drug susceptibility testing (DST) coverage and strengthened community infection control. Enhanced treatment adherence and universal pDST coverage, particularly for retreated patients and socioeconomically vulnerable populations such as farmers, are essential for effective MDR-TB containment.