Association between the aggregate index of systemic inflammation and hyperuricemia: evidence from NHANES 2011–2018

Objective The aim of this study was to explore the association between the Aggregate Index of Systemic Inflammation (AISI) and hyperuricemia, using data from the 2011–2018 cycles of the NHANES. The research sought to understand how systemic inflammation, as indicated by AISI, correlates with elevated serum uric acid levels and their potential role in the pathophysiology of hyperuricemia. Methods This cross-sectional study included 19,881 participants. AISI was calculated using neutrophil, platelet, monocyte, and lymphocyte counts, and hyperuricemia was defined as serum uric acid levels ≥ 7.0 mg/dL in males and ≥ 6.0 mg/dL in females. Multivariate logistic regression analysis, restricted cubic spline analysis and subgroup analysis were performed to assess the association between AISI and the prevalence of hyperuricemia. Additionally, sensitivity and subgroup analyses were performed to support the robustness of the association. Results The study found that 3,666 participants had hyperuricemia, and 16,215 participants were non-hyperuricemic. Those with hyperuricemia were older, had higher BMIs, and were more likely to suffer from chronic conditions like hypertension and diabetes. AISI levels were significantly higher in the hyperuricemic group compared to non-hyperuricemic participants, suggesting a positive correlation between AISI and hyperuricemia. Multivariate logistic regression revealed that for each unit increase in AISI, the prevalence of hyperuricemia increased by 42% (OR = 1.07, 95% CI = 1.06–1.08). Nonlinear analysis identified a threshold at AISI = 612, with AISI levels below this threshold significantly increasing the likelihood of hyperuricemia. Subgroup analyses showed that this association remained consistent across different demographic groups, including age, sex, and BMI. Sensitivity and additional analyses confirmed the consistency of these findings, further supporting the robustness of the association. Conclusion The findings of this study suggest a significant positive association between AISI and hyperuricemia, indicating that systemic inflammation, as measured by AISI, may contribute to the pathophysiology of hyperuricemia. Elevated AISI could potentially serve as a marker for identifying individuals at higher risk of hyperuricemia with AISI levels below 612, offering opportunities for early intervention and personalized treatment strategies. Further longitudinal studies are needed to confirm these findings and explore the underlying mechanisms.