Study links sex, smoking history and prior treatment to drug-resistant TB in Indonesia

Indonesia carries a heavy burden of tuberculosis: the country ranks second in the world for TB incidence, with a reported prevalence of 759 (95% CI: 589.7-960.8) cases per 100,000 people. To better understand which factors are connected to antibiotic resistance in TB, Yuni Rukminiati and colleagues analyzed data from a national, population-based cross-sectional study of 494 people with TB. The study used records from the Tuberculosis Drug Resistance Survey (TB-DRS) run by the Ministry of Health, Republic of Indonesia, and collected clinical and demographic information during fieldwork carried out between 2017 and 2018. Participants completed a self-report questionnaire after giving informed consent, supplying details such as education, employment, smoking history, prior attempts to seek treatment, and whether they had been treated for TB in the past. Clinical samples from these participants were sent to a National Laboratory to determine drug resistance status. The aim was simple and urgent: to reestablish which patient characteristics are associated with antibiotic-resistant TB, information that could help public health officials target surveillance and control efforts.

Laboratory testing for drug resistance relied on established diagnostic technologies: MGIT960 culture testing, GeneXpert molecular testing, and Illumina-based WGS for genomic analysis. The researchers used descriptive statistics and DATAtab software to run Chi-square tests and logistic regression, applying a significance threshold of p<0.05. The study found that many commonly suspected factors were not statistically linked to TB drug resistance in this sample: age-group (χ2=2.17, p=0.825), geographical location (χ2=0.23, p=0.893), college education (OR: 1.1, 95% CI: 0.76-1.60, p=0.617, χ2=0.25), employment (OR: 0.93, 95% CI: 0.65-1.34, p=0.712, χ2=0.14), actively smoking at the time of study (OR: 1.02, 95% CI: 0.61-1.69, p=0.951, χ2=0.00), living community (OR: 0.94, 95% CI: 0.65-1.35, p=0.735, χ2=0.11), and previous attempts to seek treatment (OR: 1.26, 95% CI: 0.84-1.89, p=0.268, χ2=1.23). By contrast, three factors were reported as statistically associated with higher antibiotic resistance: being female (OR: 1.6, 95% CI: 1.09-2.33, p=0.015, χ2=5.87), having a history of smoking (OR: 0.65, 95% CI: 0.45-0.94, p=0.021, χ2=5.36), and previously treated TB (OR: 0.02, 95% CI: 0.01-0.08, p<0.001, χ2=86.61).

The authors conclude that surveillance and control efforts for drug-resistant TB should focus on the statistically significant risk factors identified in this nationwide study. Because the data come from a large, countrywide survey and the resistance status was confirmed using MGIT960, GeneXpert, and Illumina-based WGS in a National Laboratory, these associations are grounded in robust laboratory and field methods. The mixed pattern of results—many expected factors showed no link while female sex, a history of smoking, and previous TB treatment did—suggests that program planning cannot rely on assumptions alone and needs up-to-date, local evidence to guide where to target resources. In practical terms, focusing case finding, diagnostic testing and follow-up on groups identified by the study could help to detect resistant infections earlier and reduce onward transmission. The researchers emphasize that concentrating surveillance on the significant associated factors is crucial to halt the proliferation of drug-resistant TB within the population.