Body Mass Index Trajectories and Association With Tuberculosis Risk in a Cohort of Household Contacts in Southern Africa

Larsson, Leyla ; Calderwood, Claire J ; Marambire, Edson T ; Held, Kathrin ; Banze, Denise; Mfinanga, Alfred; Madziva, Karlos; Walsh, Phoebe; Jacob, Joseph; Fernandez, Francisco Trinchan; Lungu, Patrick; Mesic, Anita; Khosa, Celso ; Minja, Lilian T; Mutsvangwa, Junior; Bhargava, Madhavi; Lauseker, Michael ; Gupta, Rishi K ; Heinrich, Norbert und Kranzer, Katharina (2025): Body Mass Index Trajectories and Association With Tuberculosis Risk in a Cohort of Household Contacts in Southern Africa. In: Clinical Infectious Diseases, ciaf222

Abstract

Background: Studies have demonstrated an inverse log-linear relationship between body mass index (BMI) and tuberculosis incidence. However, a person's BMI is dynamic and longitudinal changes may be more informative than cross-sectional assessments. We evaluate the association between cross-sectional and changing BMI and risk of tuberculosis and describe longitudinal trajectories in a high-risk cohort.

Methods: ERASE-TB was a prospective longitudinal cohort study of household contacts ≥10 years in Southern Africa (Zimbabwe, Tanzania, and Mozambique), with 6-monthly follow-up up to 24 months. Associations between BMI and tuberculosis were investigated based on baseline (including haemoglobin) and changing BMI, using logistic, Poisson, and Cox models. Prevalent tuberculosis was defined as diagnosis during <30 days after recruitment. Growth mixture modelling (GMM) was used to model longitudinal latent trajectories.

Results: Of 2,107 recruited household contacts (621 [29.5%] adolescents and 1,310 [62.2%] female), 520 (24.7%) were underweight. There were 21 and 41 people diagnosed with prevalent and incident tuberculosis, of whom 5/21 (23.8%) and 12/41 (29.3%) were underweight. Being underweight and anaemic (aHR: 3.77, 95% CI: 1.50-9.51) and >10% negative change in BMI during follow-up (aIRR: 2.27 (95% CI: 0.22-22.9) were associated with increased risk of incident tuberculosis. The association between continuous BMI-for-age Z-scores were non-linear, with increased risk of tuberculosis with lower BMI. Four latent groups were defined in the GMM: increasing, decreasing, and low/high stable BMI.

Conclusions: Declining BMI, regardless of absolute value, is a strong predictor of tuberculosis among household contacts. Longitudinal measurements should be considered in active case finding among tuberculosis-affected households.

• Dokumententyp: Zeitschriftenartikel
• Keywords: body mass index; trajectories; tuberculosis; undernutrition
• Fakultät: Medizin > Institut für Medizinische Informationsverarbeitung, Biometrie und Epidemiologie
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• ISSN: 1058-4838
• Sprache: Englisch