Correlation between Inflammatory Biomarkers and Red Blood Cell Life Span in Chronic Hemodialysis Patients

The pathogenesis of anemia in hemodialysis (HD) patients is dependent on multiple factors, with decreased red blood cell life span (RBCLS) being a significant contributor. Although the impact of reduced RBCLS on anemia is recognized, it is still a subject that is not well researched. The objective of this study was to investigate the relationship between RBCLS and inflammatory biomarkers in chronic HD patients.

RBCLS was calculated from alveolar carbon monoxide concentrations measured by gas chromatography. Interleukins (IL) IL-6, IL-18, IL-10, and high sensitivity C-reactive protein were measured using bead-based multiplex assay. Measurements were carried out at baseline and during follow-up. The associations between RBCLS and inflammatory biomarkers were evaluated using linear mixed effects models.

RBCLS measurements were available for 54 HD patients. Their average age was 58.5 ± 14.4 years, 68.5% were males, 48.1% were diabetics, and the HD vintage was 51 ± 48 months. In 4 patients, RBCLS was measured once, while in 50 patients, up to 5 repeated RBCLS measurements were available. RBCLS was 73.2 ± 17.8 days (range 37.7-115.8 days). No association was found between RBCLS and any of the inflammatory biomarkers. Of note, RBCLS was positively correlated with levels of uric acid (p = 0.02) and blood urea nitrogen (BUN; p = 0.01), respectively.

Our study suggests that inflammation pathways reported by these biomarkers only have a limited role in causing premature RBC death. The positive correlation with uric acid and BUN warrants further studies.