Nutritional problems in tuberculosis management

A study investigates the role of nutritional rehabilitation in reducing tuberculosis (TB) incidence and mortality in South-East Asia, emphasizing undernutrition as a significant risk factor. It employs a deterministic compartmental model to simulate TB transmission across 10 countries, categorizing individuals by nutritional status to assess intervention outcomes. This model is effective, enabling an in-depth analysis of how nutritional status impacts TB dynamics and intervention efficacy.[1] See also: TB control in China

Independent variables include nutritional status variations, the extent of intervention coverage, and TB service enhancements, while dependent variables measure TB incidence and mortality. Confounders such as COVID-19 disruptions and differences in healthcare infrastructure are considered, with control scenarios involving no nutritional interventions and standard TB services. This setup allows for precise evaluations of how nutritional improvements can influence TB outcomes under different conditions.[1] See also: https://tbreadingnotes.blogspot.com/2024/10/impact-of-diabetes-itself-and-glycemic.html

The results show that nutritional interventions significantly lower TB incidence and mortality, particularly in high-risk populations. For instance, in India, interventions among household contacts are projected to reduce TB incidence and mortality by 5.7% and 6.2%, respectively, by 2030. Broadening these interventions to cover 30% of the general population could lead to a 23.6% reduction in incidence and a 35.5% decrease in mortality. These findings illustrate the critical need to integrate nutritional support into comprehensive TB prevention strategies, especially in regions where undernutrition is a prevalent TB driver.[1] See also: Lin TB Lab

Malnutrition significantly elevates tuberculosis (TB) risk by impairing cell-mediated immunity (CMI), making malnourished individuals more susceptible to progressing from latent to active TB. This risk is compounded in impoverished populations where poor nutrition and higher TB incidence are interconnected. Case studies from historical contexts illustrate the impact of nutrition on TB rates.[2] See also: Spatial information for TB

During World War I, Denmark experienced increased TB rates as it exported most of its protein-rich foods. However, following a German blockade in 1918 that inadvertently improved local food availability, TB rates declined, contrasting with continued increases in neighboring countries still engaged in the war. A similar pattern was observed at the Trondheim Naval Training School in Norway, where TB rates initially remained high despite improved housing and hygiene. It was only after the diet was nutritionally fortified that TB morbidity significantly decreased.[2]

Further evidence comes from World War II, where British and Russian prisoners of war (POWs) consumed the same prison diet, but the British had access to additional food supplements from the Red Cross. This resulted in substantially lower TB rates among British POWs (1.2%) compared to their Russian counterparts (15-19%). The correlation between better nutrition, higher plasma protein levels, and reduced TB severity was evident. These cases underscore the critical need to understand the timing of malnutrition and TB onset to discern cause-effect relationships, especially since TB can cause symptoms resembling malnutrition, further complicating analyses. Additionally, vitamin supplementation among family contacts of TB patients has shown potential in reducing TB risk, suggesting broader implications for nutritional interventions in TB prevention strategies.[2]

Among dialysis patients, factors such as current smoking, shorter dialysis duration, active radiographic lesions, and fever significantly contribute to the prevalence of TB. This increased risk in individuals with renal failure can be attributed to enhanced immune cell apoptosis, lymphocyte depletion, and dysfunction of polymorphonuclear leukocytes, all of which are worsened by oxidative stress and uremic toxins. Moreover, the dialysis population inherently carries a high TB risk; while a positive QFT-GIT test indicates significant risk, there is a notable 49.6% rate of negative conversion. However, persistent positivity in QFT-GIT testing correlates with a higher hazard ratio and specificity for future TB development, underscoring the complex interplay between TB risk factors and management in vulnerable populations such as those undergoing dialysis.[3]

Cardiovascular disease was most prevalent in the diabetes mellitus (DM) group, while anemia was notably higher in the tuberculosis-diabetes mellitus (TB-DM) group. Smoking and alcohol consumption were more common among the tuberculosis (TB) group, followed by the TB-DM group. Additionally, the TB-DM group exhibited poor glycemic control, with HbA1c levels averaging 10.47%, significantly higher than the 8.17% observed in the DM group. Despite similar nutritional parameters like albumin, globulin, and total proteins across groups, vitamin B12 levels were distinctly elevated in the TB-DM group, with a vast majority (95.83%) showing HbA1c levels above 6.5.[4]

The TB group showed a significant incidence of low serum albumin (71.91%), and vitamin D deficiency was most prevalent in the TB-DM group (73.68%), suggesting more severe nutritional deficits compared to the DM (50%) and TB (42.86%) groups. The TB-DM group also faced elevated vitamin B12 levels, with 66.67% exceeding 2000 pg/ml. These patients also demonstrated significantly higher glycemic parameters and a greater prevalence of low mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH), which are indicative of anemia risk. Collectively, these findings illustrate that the coexistence of TB and DM compounds health risks, exacerbating metabolic disturbances and nutritional deficiencies, thus leading to a higher incidence of cardiovascular diseases and more challenging diabetes management.[4]

References:

1. Mandal, S., Bhatia, V., Bhargava, A., Rijal, S. and Arinaminpathy, N., 2024. The potential impact on tuberculosis of interventions to reduce undernutrition in the WHO South-East Asian Region: a modelling analysis. The Lancet Regional Health-Southeast Asia, p.100423.

2. Cegielski, J.P. and McMurray, D.N., 2004. The relationship between malnutrition and tuberculosis: evidence from studies in humans and experimental animals. The international journal of tuberculosis and lung disease, 8(3), pp.286-298.

3. Shu, C.C., Hsu, C.L., Wei, Y.F., Lee, C.Y., Liou, H.H., Wu, V.C., Yang, F.J., Lin, H.H., Wang, J.Y., Chen, J.S. and Yu, C.J., 2016. Risk of tuberculosis among patients on dialysis: the predictive value of serial interferon-gamma release assay. Medicine, 95(22), p.e3813.

4. Patel, D.G., Baral, T., Kurian, S.J., Malakapogu, P., Saravu, K. and Miraj, S.S., 2024. Nutritional status in patients with tuberculosis and diabetes mellitus: A comparative observational study. Journal of Clinical Tuberculosis and Other Mycobacterial Diseases, 35, p.100428.