Association between body mass index and newly diagnosed drug-resistant pulmonary tuberculosis in Shandong, China from 2004 to 2019

BACKGROUND: Drug-resistant tuberculosis (DR-TB), obesity, and malnutrition are growing public health problems in the world. However, little has discussed the impact of different BMI status on the emergence of TB drug resistance. We aimed to explore the drug-resistant profiles of DR-TB and its clinical predictors among underweight, overweight or obesity population. METHODS: 8957 newly diagnosed TB cases with drug susceptibility results and BMI data in Shandong China, from 2004 to 2019 were enrolled. Multivariable and univariable logistic regression models were applied to investigate the impact of BMI on different drug-resistance. Clinical predicators and drug-resistant profiles of DR-TB among obesity, underweight, normal TB group were also described. RESULTS: Among 8957 TB cases, 6417 (71.64%) were normal weight, 2121 (23.68%) were underweight, 373 (4.16%) were overweight, and 46 (0.51%) were obese. The proportion of drug resistance and co-morbidity among normal weight, underweight, overweight, obese TB groups were 18.86%/18.25%/20.38%/23.91% (DR-TB), 11.19%/11.74%/9.65%/17.39% (mono-resistant tuberculosis, MR-TB), 3.41%/3.06%/5.36%/0.00% (multidrug resistant tuberculosis, MDR-TB), 4.21%/3.39%/5.36%/6.52% (polydrug resistant tuberculosis, PDR-TB), 10.57%/8.44%/19.57%/23.91% (co-morbidity), respectively. Compared with normal weight group, underweight were associated with lower risk of streptomycin-related resistance (OR 0.844, 95% CI 0.726–0.982), but contributed to a higher risk of MR-TB (isoniazid) (odds ratio (OR) 1.347, 95% CI 1.049–1.730; adjusted OR (aOR) 1.31, 95% CI 1.017–1.686), P < 0.05. In addition, overweight were positively associated with MDR-TB (OR 1.603, 95% CI 1.002–2.566; aOR 1.639, 95% CI 1.02–2.633), isoniazid + rifampicin + streptomycin resistance (OR 1.948, 95% confidence interval (CI): 1.061–3.577; aOR 2.113, 95% CI 1.141–3.912), Any isoniazid + streptomycin resistance (OR 1.472, 95% CI 1.013–2.14; aOR 1.483, 95% CI 1.017–2.164), P < 0.05. CONCLUSIONS: The higher risk of MDR-TB, isoniazid + rifampicin + streptomycin resistance, Any isoniazid + streptomycin resistance, and co-morbidity among overweight population implies that routine screening for drug sensitivity and more attention on co-morbidity among overweight TB cases may be necessary. In addition, underweight TB cases have a higher risk of isoniazid resistance. Our study suggests that an in-depth study of the interaction between host metabolic activity and infection of DR-TB may contribute more to novel treatment options or preventive measures, and accelerate the implementation of the STOP TB strategy.