C-reactive protein-to-albumin ratio and six-month mortality in incident hemodialysis patients

Abstract

Background

The first few months of hemodialysis (HD) are associated with a higher risk of mortality. Protein-energy malnutrition is a demonstrated major risk factor for mortality in this population. The C-Reactive Protein to Albumin ratio (CAR) has also been associated with increased mortality risk. The aim of this study was to determine the predictive value of CAR for six-month mortality in incident HD patients.

Methods

Retrospective analysis of incident HD patients between January 2014 and December 2019. CAR was calculated at the start of HD. We analyzed six-month mortality. A Cox regression was performed to predict six-month mortality and the discriminatory ability of CAR was determined using the receiver operating characteristic (ROC) curve.

Results

A total of 787 patients were analyzed (mean age 68.34 ± 15.5 years and 60.6% male). The 6-month mortality was 13.8% (n = 109). Patients who died were significantly older (p < 0.001), had more cardiovascular disease (p = 0.010), had central venous catheter at the start of HD (p < 0.001), lower parathyroid hormone (PTH) level (p = 0.014) and higher CAR (p = 0.015). The AUC for mortality prediction was 0.706 (95% CI (0.65–0.76), p < 0.001). The optimal CAR cutoff was ≥0.5, HR 5.36 (95% CI 3.21–8.96, p < 0.001).

Conclusion

We demonstrated that higher CAR was significantly associated with a higher mortality risk in the first six months of HD, highlighting the prognostic importance of malnutrition and inflammation in patients starting chronic HD.

Keywords:

• Hemodialysis
• mortality
• inflammation
• malnutrition

Acknowledgements

None.

Ethical approval and consent to participate

The study was approved by the Ethical Committee at the Centro Hospitalar Universitário Lisboa Norte, EPE. Due to the retrospective and non-interventional nature of the study, informed consent was waived by the Ethical Committee.

Consent for publication

Not applicable.

Author contributions

MS was involved in acquisition of data and drafting the manuscript. BMS, CB, CC, NP, AC, AMA, JF participated in the acquisition of data. CO, CR, JAL were involved in the critical revision of the manuscript. JG made substantial contributions to the study concept and design, analysis and interpretation of data, and revision of the manuscript.

Disclosure statement

The results presented in this paper have not been published previously in whole or part, except in abstract format.

Data availability statement

Please contact author for data requests.

Additional information

Funding

No funding was received for this study.