Levels of Selenium and Magnesium Impact Asthma Patients: Finds Scientific Reports - Video

Scientists at the Chongqing Medical University, China, have conducted a study to investigate the association between blood levels of heavy metals and all-cause mortality among adult patients with asthma.

The study is published in the journal Scientific Reports.

Asthma is a respiratory disease caused by bronchospasm and airway inflammation. The most common symptoms are breathing difficulty, chest constriction, wheezing, coughing, and thick mucus production.

The prevalence of asthma is increasing steadily worldwide, partly because of increasing environmental exposure to allergens, air pollutants, and tobacco smoke. Currently, more than 350 individuals are living with asthma worldwide, and around 250,000 annual fatalities are directly linked to the condition.

Heavy metals, including lead, cadmium, mercury, and manganese, are ubiquitous in the environment and can enter the lungs and bloodstream through ingestion of food or water and inhalation of polluted air. Exposure to these heavy metals can trigger inflammation and oxidative stress, which in turn can cause lung damage and premature death.

Selenium is a micronutrient that plays a vital role in reducing oxidative stress and improving immune response. It has a multifactorial relationship with respiratory diseases, including asthma.

Existing evidence indicates that low blood levels of selenium increase the risk of developing asthma; however, both deficient and excessive levels of selenium can be harmful.

In this study, scientists have evaluated the associations between blood levels of heavy metals and all-cause mortality in adult asthma patients.

For the study, the scientists screened National Health and Nutrition Examination Survey (NHANES) data and identified 2,432 adult asthma patients for the study analysis. They obtained patient data on blood levels of certain heavy metals, including lead, cadmium, mercury, selenium, and manganese.

The study found that a higher blood selenium level is associated with a significantly lower all-cause mortality in asthma patients. In contrast, a significant positive association was observed between blood manganese level and all-cause mortality among participants. However, it is important to note that the study found a significant U-shaped relationship for both selenium and manganese, indicating that both very low and very high levels of these metals are associated with higher mortality.

Findings suggest that modifying the amount of selenium in the diet and managing exposure to manganese could potentially improve the prognosis for individuals with asthma.

Reference: Liao, J., Wen, J., Wei, C. et al. Association between blood heavy metal element and all-cause mortality in asthmatic adults: a cohort study. Sci Rep 14, 20457 (2024). https://doi.org/10.1038/s41598-024-70250-8