biostudies-literatureUnknown15(1)Zhang HVitamin D deficiency and elevated CRP (C-reactive protein) levels are independent indicators of risk for mortality in cancer survivors; however, their combined association with mortality has not been examined. This study included adult cancer survivors from four NHANES cycles (2003-2010), utilizing a multistage survey design. CRP levels were measured using a latex-enhanced turbidimetric assay, and serum 25(OH)D levels were assessed using RIA and LC-MS/MS methods. Mortality data were linked with the National Death Index up to 2019. The restricted cubic spline model was used to explore the nonlinear associations with mortality. Kaplan-Meier analysis was used to examine survival curve differences. Cox analysis was employed to assess mortality risk after adjusting for confounding factors, and Scientific reports14798https://www.ebi.ac.uk/biostudies/studies/S-EPMC12038049biostudies-literatureInteraction effects between serum 25(OH)D and CRP status on cancer related mortality in adult cancer survivors.PMC12038049Zhang HChen XSun XDou BfalseInteraction effects between serum 25(OH)D and CRP status on cancer related mortality in adult cancer survivors.Vitamin D deficiency and elevated CRP (C-reactive protein) levels are independent indicators of risk for mortality in cancer survivors; however, their combined association with mortality has not been examined. This study included adult cancer survivors from four NHANES cycles (2003-2010), utilizing a multistage survey design. CRP levels were measured using a latex-enhanced turbidimetric assay, and serum 25(OH)D levels were assessed using RIA and LC-MS/MS methods. Mortality data were linked with the National Death Index up to 2019. The restricted cubic spline model was used to explore the nonlinear associations with mortality. Kaplan-Meier analysis was used to examine survival curve differences. Cox analysis was employed to assess mortality risk after adjusting for confounding factors, and 2025-01-01T00:00:00Z2025 Apr2025-07-04T03:06:06.319Z2025-07-04T03:06:06.319ZS-EPMC120380494029551810.1038/s41598-025-95931-w