Association of dietary caffeine intake and metabolites in the urine of individuals with latent tuberculosis infection: a cross-sectional study

Abstract

Abstract Background Currently, there is insufficient evidence available regarding the association between dietary caffeine intake and latent tuberculosis infection (LTBI). The aim of this study was to elucidate the impact of dietary caffeine intake and urinary caffeine metabolite levels on LTBI. Methods We conducted a prospective cohort study using data from the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2012. We used multivariate logistic regression to explore the relationship between dietary caffeine intake and LTBI prevalence, and adjusted for confounding factors. At the same time, we measured the level of caffeine metabolites in the urine. Results The mean dietary caffeine intake was 94.0 mg (12.0–205.0 mg) in the non-LTBI group and 71.0 mg (11.2–160.0 mg) in the LTBI group (P<0.05). Multivariable-adjusted regression revealed that the participants with a dietary caffeine intake of ≥ 150 mg/day have lower odds of LTBI compared with the participants with a dietary caffeine intake<150 mg/day ( OR [odds ratio] 0.70, 95% confidence interval 0.54–0.91). In subgroup analysis, LTBI correlated negatively with age < 65 years, the male sex, the Mexican American ethnicity, a body mass index of 25 to < 30 kg/m2, and diabetes (Ps<0.05). Caffeine metabolites such as 1-methyl-uric acid and 1,7-dimethyl-uric acid were significantly lower in urine from the participants with LTBI (Ps<0.05). Conclusions A lower dietary caffeine intake was proportionally related to LTBI. The findings presented in this study should be validated and investigated further.

Keywords

• Caffeine
• Metabolites
• Latent tuberculosis infection
• Nutrition