The interplay of insulin resistance and systemic inflammation on cancer history: a nationally representative cross-sectional study from NHANES

Abstract Aim To investigate whether systemic inflammation, measured by the neutrophil-to-lymphocyte ratio (NLR), modifies the cross‑sectional association between insulin resistance (IR, assessed by HOMA-IR) and overall cancer history in a nationally representative population. Methods We conducted a cross-sectional analysis utilizing data from the 2017–2018 National Health and Nutrition Examination Survey (NHANES), which employs a complex, multistage probability sampling design. All analyses accounted for the complex survey design and sampling weights to ensure national representativeness. Weighted multivariable logistic regression was used to assess the cross‑sectional association, with an interaction term between HOMA-IR and NLR. Results Among 3,746 adults, after adjusting for age, sex, and BMI, HOMA-IR was not independently associated with cancer history (OR = 1.00, 95% CI 0.98–1.02). The HOMA-IR × NLR interaction term was not statistically significant (P for interaction = 0.359), indicating no significant effect modification by NLR. Conclusion In this nationally representative sample, we found no evidence that systemic inflammation, as measured by NLR, amplifies the cross‑sectional association between IR and overall cancer history. The potential synergistic effect may be confined to specific high-risk subgroups or inflammatory pathways.