Association between fifteen peripheral blood inflammatory markers and cancer prevalence: a cross-sectional study based on NHANES and a Chinese hospital cohort

Background Chronic low-grade inflammation has been associated with cancer, but comparative data on routine inflammatory markers in individuals with a history of cancer (prevalent cancer) remain limited. We examined associations between 15 peripheral blood inflammatory markers and cancer prevalence in a US general population and a Chinese hospital cohort. Methods We analyzed the NHANES cohort and a hospital cohort from the Second Affiliated Hospital of Kunming Medical University. Fifteen markers were calculated from routine blood tests. Weighted multivariable logistic regression, restricted cubic splines, and subgroup analysis were used. Results In NHANES, MLR, NMLR, SIRI, NLR, CAR, CLR, HALP, IBI, and NPAR were positively associated with cancer prevalence in continuous analysis, whereas PAR was inversely associated; LMR showed a significant nonlinear inverse association (P overall < 0.0001, P nonlinear = 0.0189) only in quartile analysis (Q4 OR = 0.64, 95% CI: 0.51–0.80). In the hospital cohort, MLR, NMLR, SIRI, SII, NLR, PLR, CAR, CLR, PIV, IBI, NPAR, and PAR were positively associated with cancer prevalence, while LMR and CALLY were inversely associated. In the overall NHANES cohort, MLR, NMLR, SIRI, SII, NLR, PIV, IBI, and NPAR were associated with higher all-cause mortality (2,257 deaths among 17,644 participants), whereas LMR and CALLY were associated with lower mortality. Conclusion Peripheral blood inflammatory markers are cross-sectionally associated with cancer prevalence and with mortality among cancer survivors. These findings do not establish incident cancer risk, causality, screening performance, or clinically actionable risk thresholds. Prospective studies are needed.