| Objective To analyze the drug resistance characteristics and trends of clinically isolated Mycobacterium tuberculosis（MTB） in elderly tuberculosis patients（≥60 years old） in Anhui province, and to provide reference data for optimizing clinical anti-tuberculosis treatment regimens and formulating scientific prevention and control strategies. Methods A retrospective study was used to collect the results of drug susceptibility testing and clinical data of elderly tuberculosis patients attending Anhui Provincial Chest Hospital from January 2022 to December 2024. The overall drug resistance rate, multidrug resistance（MDR） rate, pre-extensively drug resistant（pre-XDR） rate, and resistance rate to six anti-tuberculosis drugs: isoniazid（INH）, rifampicin（RIF）, streptomycin（Sm）, ethambutol（EMB）, moxifloxacin（MFX）, and levofloxacin（LFX） were all analyzed. Resistance rates across different genders, age groups, treatment types, and patients with comorbidities were compared. The drug resistance spectrum among MDR and pre-XDR strains, trends in resistance rates from 2022 to 2024, and cross-resistance between MFX and LFX were analyzed. χ2 tests or Fisher’s exact probability test were employed for group comparisons, and the χ2 trend test was utilized to analyze the trend of changes in drug resistance rate Results A total of 1 544 MTB strains were included for analysis, with an overall resistance rate of 21.18%（327/1 544）, MDR rate of 5.63%（87/1 544）, and pre-XDR rate of 2.85%（44/1 544）. The resistance rates for the six anti-tuberculosis drugs were ranked as follows: INH（13.08%）, Sm（10.36%）, RIF（9.97%）, MFX（6.15%）, LFX（4.53%）, and EMB（1.81%）. Male patients had higher rates of INH resistance and RIF resistance than female patients（P ＜0.05）; the group aged 60～69 years had the highest total resistance rate（23.25%）; and the rates of total resistance, INH, RIF, and Sm resistance in patients of various ages were statistically significant（P ＜0.05）. The rates of drug resistance in all categories were higher in retreatment patients than in treatment-naive patients（P ＜0.05）. Patients with concomitant chronic pulmonary diseases had significantly higher overall drug resistance rates, MDR rates, pre-XDR rates, and drug resistance rates for INH, RIF, EMB, and MFX（P ＜ 0.05）. There were 16 drug-resistant combinations in the resistance profiles of 131 MDR and pre-XDR strains, and the highest resistance rate was found in the combination of “INH + RIF”（2.53%, 39/1 544）. From 2022 to 2024, the drug resistance rate of MDR strains and RIF resistance rate showed a downward trend（P ＜0.05）; the resistance rate of MFX and LFX showed an upward trend（P ＜0.05）, and there was cross-drug resistance. Conclusion The drug-resistant situation of elderly tuberculosis patients in Anhui province is still severe, and measures such as drug-resistant monitoring and rational drug interventions need to be strengthened to reduce the generation and spread of drug-resistant tuberculosis. |
