AUTHOR=Tian Tulei , Xie Meiling , Sun Gengyun 

TITLE=Association of systemic immune-inflammation index with asthma and asthma-related events: a cross-sectional NHANES-based study

JOURNAL=Frontiers in Medicine

VOLUME=Volume 11 - 2024

YEAR=2024

URL=https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2024.1400484

DOI=10.3389/fmed.2024.1400484

ISSN=2296-858X

ABSTRACT=Background: Asthma is associated with persistent airway inflammation, and numerous studies have investigated inflammatory markers causing asthma. However, the systemic immune inflammation index (SII) is a novel inflammatory marker, with scarce research reporting on the correlation between SII and asthma and asthma-related events. This study assessed the relationship between SII and asthma and asthma-related events using data from the National Health and Nutrition Examination Survey (NHANES) 2009-2018.
Methods: Multifactor logistic regression was employed to assess the correlation between SII and asthma and asthma-related events. Smoothed curve fitting and threshold effects analyses were also carried out to determine the presence of nonlinear relationships. Subgroup analyses were performed to identify sensitive populations.
Results: The study analyzed data from 40,664 participants. The findings indicated a positive correlation between SII and asthma, with a relative risk increase of 0.03% for asthma incidence per one percentage point increase in SII (OR = 1.0003, 95% CI: 1.0002, 1.0004). For individuals still suffering from asthma, higher SII also indicated a positive correlation with ongoing asthma (OR = 1.0004, 95% CI: 1.0001, 1.0006). No statistically significant association was observed between SII and asthma exacerbations within the following year (OR = 1.0001, P > 0.05). A slight positive correlation was observed between SII and asthma duration (β = 0.0017, 95% CI: 0.0005, 0.0029), with a significant non-linear relationship at the threshold of 504.3 (β = 0.0031, 95% CI: 0.0014-0.0048, P = 0.0003). Subgroup analysis revealed stronger correlations in males and individuals aged 60 and above for asthma, and in participants under 20 years old for ongoing asthma.
Conclusion: SII is positively correlated with the persistence of asthma, yet has limited predictive power for asthma recurrence. This highlights SII's potential as a tool for assessing asthma risk and formulating targeted management strategies.