Impact of alcohol drinking and tobacco smoking on the drug-resistance of newly diagnosed tuberculosis: a retrospective cohort study in Shandong, China, during 2004–2020

OBJECTIVES: To investigate the independent and collective impact of alcohol drinking and tobacco smoking on the drug-resistance of newly diagnosed tuberculosis (TB). DESIGN: This was a retrospective cohort study. SETTING: Shandong, China. PARTICIPANTS: Patients with newly diagnosed TB from 1 January 2004 to 31 December 2020 were collected. Exclusive criteria: retreated cases; extrapulmonary tuberculosis; without information on drug susceptibility testing results, smoking or drinking habits; bacteriological identification as non-tuberculous mycobacteria. PRIMARY AND SECONDARY OUTCOME MEASURES: Patients were classified into four groups including smokers only (G(1)), drinker only (G(2)), smoker +drinker (G(3)), non-smoker +non-drinker group (G(0)). We described the drug-resistant profiles, clinical factors and calculated the ORs of different drug-resistance among G(1), G(2), G(3), compared with G(0) through univariate and multivariate logistics regression models. RESULTS: Of the 7996 TB cases enrolled, the proportions of G(1), G(2), G(3) and G(0) were 8.25%, 3.89%, 16.46% and 71.40%, respectively. The rates of drug-resistant (DR)-TB, mono-resistant TB, multidrug resistant (MDR)-TB, polydrug resistant TB in G(1,) G(2), G(3) and G(0) were 19.24%/16.4%/17.33%/19.08%, 11.52%/8.68%/10.94%/11.63%, 3.03%/2.57%/2.96%/3.66% and 4.70%/4.82%/3.34%/ 4.08%, respectively. G(3) had a higher risk of MDR1: isoniazid +rifampin (adjusted OR (aOR)=1.91, 95% CI: 1.036 to 3.532), but had a lower risk of DR-TB (aOR=0.84, 95% CI: 0.71 to 0.99), rifampin-related resistance (aOR=0.68, 95% CI: 0.49 to 0.93), streptomycin-related resistance (aOR=0.82, 95% CI: 0.68 to 0.99), ethambutol-related resistance (aOR=0.57, 95% CI: 0.34 to 0.95), MDR3: isoniazid +rifampin+streptomycin (aOR=0.41, 95% CI: 0.19 to 0.85), any isoniazid +streptomycin resistance (aOR=0.85, 95% CI: 0.71 to 1.00). However, there were no significant differences between G(1) and G(0), G(2) and G(0) in all drug-resistant subtypes. Those patients with cavity had a higher risk of DR-TB among G(3) (OR=1.35, 95% CI: 1.01 to 1.81). CONCLUSION: Although we did not found an independent impact of alcohol drinking or tobacco smoking on TB drug-resistance, respectively, these two habits had a combined effect on TB drug-resistance.