With the rising incidence and mortality rates of cancer, there is an urgent need for effective biomarkers to predict cancer occurrence and monitor its prognosis. The red blood cell distribution width to albumin ratio (RAR), a novel inflammatory biomarker, has inconclusive associations with both cancer occurrence and prognosis. This study aims to explore the relationship between RAR and cancer incidence, as well as the prognosis of cancer survivors. we included 21,452 U.S. adults from the National Health and Nutrition Examination Survey 2005 to 2016, of whom 1910 were cancer survivors. The association between RAR and cancer incidence was assessed using weighted multivariable logistic regression. The relationship between RAR and mortality in cancer survivors was evaluated using weighted multivariable Cox proportional hazards models and sensitivity analyses. The outcomes assessed were all-cause and cancer-specific mortality. After full adjustment for confounders, no significant association was found between RAR and cancer incidence. However, each unit increase in RAR was significantly associated with increased all-cause mortality (hazard ratio 2.42, 95% confidence interval CI: 1.93-3.03) and cancer-specific mortality (hazard ratio 2.49, 95% CI: 1.79-3.47) in cancer survivors. This positive association was consistent across all predefined subgroups. A prognostic model incorporating RAR demonstrated moderate discriminative ability, with a C-index of 0.76 and time-dependent areas under the curve for 5- and 10-year survival of 0.77 and 0.83, respectively. RAR is an independent prognostic factor for both all-cause and cancer-specific mortality in cancer survivors, suggesting its potential utility as a prognostic biomarker. The model shows moderate accuracy, warranting external validation to confirm its clinical utility.
Li et al. (Fri,) studied this question.