Underweight people at greater risk of tuberculosis
There appears to be an inverse correlation between body mass index (BMI) and the risk of tuberculosis, especially in the underweight population, a recent study has found.
Researchers conducted a large population-based cohort study including more than 10 million individuals, whose data were retrieved from the 2010–2017 database of the Korean National Health Insurance.
Over more than 70 million person-years of follow-up, 52,615 individuals developed active TB, resulting in an incidence rate of 0.75 per 1,000 person-years. Multivariable Cox regression analysis found an overall log-linear inverse correlation between BMI and the incidence of tuberculosis, particularly in the BMI range 15–30 kg/m2.
For instance, those with BMI <18.5 kg/m2 were more than twice as likely to contract tuberculosis than normal-weight participants (adjusted hazard ratio [HR], 2.08, 95 percent confidence interval [CI], 2.02–2.15). Meanwhile, the risk of tuberculosis was approximately halved in overweight (adjusted HR, 0.56, 95 percent CI, 0.55–0.58) and obese (adjusted HR, 0.40, 95 percent CI, 0.39–0.41) individuals.
Of note, the degree of thinness in the underweight population further aggravated tuberculosis risk. Mild thinness was associated with an adjusted HR of 1.98 (95 percent CI, 1.91–2.05), while risk estimates were much higher for those with moderate (adjusted HR, 2.50, 95 percent CI, 2.33–2.68) and severe (adjusted HR, 2.83, 95 percent CI, 2.55–3.15) thinness (ptrend<0.001).