High Prevalence of Resistance to First-Line Drugs and Multidrug Resistance in Patients with Tuberculosis and Type 2 Diabetes Mellitus at a Referral Hospital in Peru

IntroductionThe coexistence of tuberculosis (TB) and type 2 diabetes mellitus (T2DM) poses an emerging public health challenge, especially in high-TB-burden settings such as Peru. This comorbidity has been linked to unfavorable clinical outcomes and a higher likelihood of developing drug-resistant TB. ObjectiveTo estimate the prevalence of resistance to first-line antituberculosis drugs and identify factors associated with multidrug resistance (MDR) among patients with T2DM and pulmonary TB treated at a public hospital in Lima, Peru. MethodsA cross-sectional study was conducted using secondary data from 130 adults with T2DM and microbiologically confirmed pulmonary TB managed at Hospital Maria Auxiliadora between 2015 and 2019. Drug susceptibility results were categorized as sensitive, monoresistant, polyresistant, or MDR. Factors associated with MDR and resistance to at least one drug were evaluated using Poisson regression models with robust variance. ResultsThe prevalence of resistance to at least one first-line drug was 34.6%, and the prevalence of MDR-TB was 21.5%. The most frequent resistances were to isoniazid (31%) and rifampicin (27%). In the multivariable analysis, age [≥]70 years (PR = 4.13; 95% CI: 1.16-14.7) and age 40-49 years (PR = 2.99; 95% CI: 1.00-8.97) were independently associated with MDR-TB. Furthermore, a T2DM duration [≥]5 years was significantly associated with resistance to at least one drug (adjusted PR {approx} 2.1). ConclusionPatients with T2DM and pulmonary TB show a high prevalence of drug resistance, including MDR-TB. Older age and longer duration of diabetes are significant risk factors. These findings highlight the need for integrated TB-diabetes management strategies to strengthen early detection and control of drug-resistant TB in this vulnerable population.