NUTRI-TB—Levering the Nutritional Status for Tuberculosis Detection
Undernutrition is an important, yet little-researched, risk factor for tuberculosis. According to estimates, it is responsible for more cases of the disease than HIV or diabetes. Previous findings are based predominantly on body mass index (BMI), which is only of limited significance for assessing nutritional status. This proof-of-concept study will examine the relationship between nutrition and tuberculosis by analyzing stored samples and longitudinal data from the ERASE-TB cohort. The ERASE-TB cohort comprises over 2,000 household contacts of tuberculosis patients in Zimbabwe, Tanzania, and Mozambique. The study aims to characterize participants' nutritional status at the beginning of the study and evaluate the relationship between nutrition and tuberculosis occurrence. Additionally, the nutritional status of individuals who develop tuberculosis will be compared to those who remain healthy. This study will provide valuable insights into the role of nutrition in tuberculosis risk and progression.
Why is nutrition so important when it comes to tuberculosis?
Proper nutrition is fundamental to health and plays a central role in fighting infections. Although malnutrition is considered one of the most important risk factors for tuberculosis (TB), it has received little research attention to date. Malnutrition is responsible for more than twice as many TB cases as other known risk factors, such as HIV or diabetes. It is estimated that about 15% of all TB cases are due to malnutrition, compared to 7.6% associated with HIV.
TB and malnutrition often occur together and influence each other. This close interaction makes it difficult to identify clear causal relationships and understand the direction of the relationship.
Why BMI alone is not sufficient
Body mass index (BMI) is often used to assess nutritional status. Although this measure is simple, inexpensive, and non-invasive, it provides only limited meaningful results. Reduced food intake is only reflected in BMI only after a delay, and the values correlate weakly with biochemical or immunological markers of malnutrition. Previous studies on the relationship between nutrition and tuberculosis have relied exclusively on BMI.
The NUTRI-TB project addresses this issue by investigating the influence of micronutrient deficiencies and other biochemical markers of malnutrition on the risk of developing tuberculosis.
How the study is conducted
NUTRI-TB uses data and samples from the ERASE-TB cohort, which is funded by the European and Developing Countries Clinical Trials Partnership (EDCTP). This prospective longitudinal study is being conducted in Zimbabwe, Tanzania, and Mozambique, aiming to develop and validate new diagnostic methods for tuberculosis.
A total of 2,109 household contacts of individuals with microbiologically confirmed pulmonary tuberculosis were included in the study. Participants are followed up every six months over a period of 24 months. Each visit includes a tuberculosis examination, blood samples for storage in a biobank, and anthropometric measurements.
This extensive dataset offers a unique opportunity to analyze nutritional status at the beginning of the study, changes in nutritional status over time, and the relationship between nutrition and tuberculosis occurrence.
The three work packages of NUTRI-TB
The NUTRI-TB proof-of-concept study is divided into three work packages based on the data and samples collected as part of ERASE-TB.
- Work package 1: Description of the nutritional status of household contacts of tuberculosis patients at the time of diagnosis of the index case
- Work package 2: Analysis of the relationship between nutritional status and the occurrence of tuberculosis in household contacts
- Work package 3: Comparison of the nutritional trajectories of individuals who develop tuberculosis with those who remain healthy
Expected insights of NUTRI-TB
By investigating various markers of nutritional status and their relationship to tuberculosis, NUTRI-TB provides new scientific insights into the interaction between nutrition and infectious diseases.
The results may contribute to
- developing targeted nutritional measures for the prevention of tuberculosis,
- improving TB diagnostics by combining nutritional biomarkers with other parameters,
- optimizing treatment outcomes through accompanying nutritional support.
Thus, NUTRI-TB makes an important contribution to improving tuberculosis prevention and therapy in regions with a high disease burden.
