Spectrum of blood viscosity, albumin/fibrinogen ratio, and red cell distribution width in newly diagnosed multiple myeloma patients: an observational study

Background and aims
Multiple myeloma (MM) is a malignant plasma cell disorder characterized by clonal proliferation within the bone marrow, leading to bone destruction, anemia, renal failure, and immune dysfunction. The albumin/fibrinogen ratio (AFR), red cell distribution width (RDW), and calculated whole blood viscosity (cWBV) have emerged as potential prognostic markers reflecting inflammation, nutritional status, and hemorheological properties. However, literature reports remain inconsistent, and their prognostic significance in newly diagnosed patients has not been clearly defined. This study aimed to evaluate the prognostic value of AFR, RDW, and cWBV in predicting overall survival in newly diagnosed MM patients using readily available laboratory indices.


Patients and methods
This was a prospective observational cohort study conducted at the Hematology Unit, Assiut University Hospital, from April 2023 to April 2025. A total of 48 patients with newly diagnosed MM, defined according to International Myeloma Working Group 2016 criteria, were enrolled. Clinical data, complete blood count, serum albumin, fibrinogen, and total protein were obtained at diagnosis. AFR and cWBV were computed using validated formulas. RDW was derived from the automated blood count. Survival analysis used Kaplan–Meier curves and log-rank tests. Univariate and multivariate Cox regression analyses were used to assess predictors of overall survival. Receiver-operating characteristic curves were used to determine diagnostic performance and optimal cutoff values. Correlations with the percentage of plasma cells in the bone marrow, renal insufficiency, and lytic lesions were evaluated.


Results

Elevated RDW and decreased AFR values were significantly associated with poor survival. AFR was 9.3 ± 2.4 among survivors versus 6.7 ± 1.7 in nonsurvivors (
P
<0.001). Median RDW was 15.6 versus 17.9% (
P
=0.008). No significant difference in cWBV was observed (
P
=0.203). Kaplan–Meier showed significant associations for AFR (
P
=0.012) and RDW (
P
=0.039), but not cWBV (
P
=0.170). AFR had the highest prognostic accuracy compared with RDW. Multivariate Cox regression confirmed RDW as an independent predictor (
P
=0.003), whereas AFR approached significance (
P
=0.056).



Conclusion
AFR and RDW are simple and readily available prognostic markers, while cWBV was not predictive.