|Risk of self-reported symptoms or diagnosis of active tuberculosis in relationship to low body mass index, diabetes and their co-occurrence|
||Prince, L, Andrews, JR, Basu, S, and Goldhaber-Fiebert, JD
||Tropical Medicine and International Health, 21(10): 1272-1281; DOI: 10.1111/tmi.12763
Body Mass Index (BMI)
||Objective: Globally, tuberculosis prevalence has declined, but its risk factors have varied across place and time – low body mass index (BMI) has persisted while diabetes has increased. Using India's National Family Health Survey (NFHS), wave 3 and World Health Survey (WHS) data, we examined their relationships to support projection of future trends and targeted control efforts.
Methods: Multivariate logistic regressions at the individual level with and without diabetes/BMI interactions assessed the relationship between tuberculosis, diabetes and low BMI and the importance of risk factor co-occurrence. Population-level analyses examined how tuberculosis incidence and prevalence varied with diabetes/low BMI co-occurrence.
Results: In NFHS, diabetic individuals had higher predicted tuberculosis risks (diabetic vs. non-diabetic: 2.50% vs. 0.63% at low BMI; 0.81% vs. 0.20% at normal BMI; 0.37% vs. 0.09% at high BMI), which were not significantly different when modelled independently or allowing for risk modification with diabetes/low BMI co-occurrence. WHS findings were generally consistent. Population-level analysis found that diabetes/low BMI co-occurrence may be associated with elevated tuberculosis risk, although its predicted effect on tuberculosis incidence/prevalence was generally =0.2 percentage points and not robustly statistically significant.
Conclusions: Concerns about the additional elevation of tuberculosis risk from diabetes/low BMI co-occurrence and hence the need to coordinate tuberculosis control efforts around the nexus of co-occurring diabetes and low BMI may be premature. However, study findings robustly support the importance of individually targeting low BMI and diabetes as part of ongoing tuberculosis control efforts.
Keywords: body mass index; diabetes; nutrition; risk factor; tuberculosis; underweight