Association between Serum C-Reactive Protein Concentrations and Risk of Cancer-Related Mortality in Patients Undergoing Hemodialysis: 10-Year Outcomes of the Q-Cohort Study

Abstract

Introduction: Cancer constitutes a major source of morbidity and mortality among people undergoing hemodialysis (HD). A systemic inflammatory response is associated with the incidence and prognosis of cancer in the general population. However, the effect of systemic inflammation on cancer-related mortality in patients undergoing HD remains unclear. Methods: We analyzed 3,139 patients registered in the Q-Cohort Study, which is a multicenter, observational cohort study of patients on hemodialysis in Japan. The primary outcome was cancer-related mortality during a 10-year follow-up. The covariate of interest was serum C-reactive protein (CRP) concentrations at baseline. The patients were divided into tertiles based on their serum CRP concentrations at baseline (tertile [T] 1: ≤0.07; T2: 0.08–0.24; and T3: ≥0.25). The association between serum CRP concentrations and cancer-related mortality was calculated using the Cox proportional hazards model and the Fine-Gray subdistribution hazards model with non-cancer-related death as a competing risk. Results: During the 10-year follow-up, 216 patients died of cancer. In the multivariable analysis, the risk of cancer-related mortality in the highest tertile (T3) of serum CRP concentrations was significantly higher than that in the lowest tertile (T1) (multivariable-adjusted hazard ratio [95% confidence interval]: 1.68 [1.15–2.44]). This association remained consistent in the competing risk model, in which the subdistribution hazard ratio was 1.47 and the 95% confidence interval was 1.00–2.14 for T3 compared with T1. Conclusion: Higher serum CRP concentrations are associated with an increased risk of cancer-related mortality in patients undergoing maintenance HD.