2025 / 02 Distinguished Investigator Shau-Ku Huang (Kaohsiung Municipal Siaogang Hospital)

The increasing prevalence of asthma is largely attributed to environmental factors, yet the specific causes driving its significant phenotypic heterogeneity remain unclear. Acrylamide is a known neurotoxin and reproductive toxin encountered through occupation, smoking, and diet, but its impact on asthma and the immune system is undefined. This study aimed to evaluate the association between acrylamide exposure and various asthma phenotypes. A case-control study was conducted in Taiwan with 365 participants with current asthma and 235 healthy controls. Urinary levels of acrylamide metabolites were measured as biomarkers of exposure. Participants were categorized into phenotypic clusters (A–F) based on characteristics such as age of onset, smoking history, atopy, and BMI. Logistic and multinomial logistic regression analyses were used to assess the association between exposure levels and asthma risk. Asthma patients exhibited significantly higher urinary acrylamide metabolite levels than controls (median: 15.99 vs. 12.82 μg/g creatinine; p < 0.001). Higher exposure was associated with an increased risk of current asthma (OR: 1.52). Risk varied significantly by phenotype, with the highest odds ratios observed in Cluster E (young male smokers) and Cluster A (older non-atopic females). Significant associations were also found in Clusters C, D, and F. Exposure sources included smoking, second-hand smoke, daily vehicle transportation, and commercial occupations. Furthermore, urinary acrylamide metabolites correlated significantly with the oxidative stress marker HEL, particularly in Clusters A and B. This study provides novel evidence linking acrylamide exposure to adult asthma and highlights that susceptibility varies across different phenotypes. The findings suggest that acrylamide is a critical environmental risk factor, potentially mediated by oxidative stress. Future longitudinal studies with comprehensive dietary and occupational data are needed to further understand its role in asthma control.

Application and Highlights:

1. Phenotypic Heterogeneity: Through clustering analysis, the research highlights that acrylamide does not affect all asthma patients equally. It revealed differential risks across six distinct phenotypic clusters (A–F), showing that certain groups are more vulnerable to this specific environmental factor.
2. Precision Prevention: By identifying high-risk clusters—such as Cluster E (young male smokers) and Cluster A (older non-atopic females)—healthcare providers can offer more targeted advice on avoiding specific exposure sources like smoke or environmental pollutants.
3. Raising clinical diagnostic awareness: This study urges asthma researchers to consider acrylamide as a critical environmental factor. This would aid clinicians in evaluating patients with poorly controlled asthma by prompting them to consider the history of environmental chemical exposure.

More Information:
Hsu YT, Wu CC, Wang CC, Sheu CC, Yang YH, Cheng MY, Lai RS, Cheng MH, Chen HC, Yang CJ, Wang CJ, Liu HJ, Chen HL, Hung CH, Lee CL, Huang MS, Huang SK. Differential Risks of Exposure to Acrylamide in Adult Asthma Clusters. Allergy. 2025;80(4):1173-1175. (SCIE, IF₂₀₂₄: 12.0, 1/40=2.50% in ALLERGY)