Albumin-Corrected Serum Calcium as a Biochemical Correlate of Left Ventricular Dysfunction Among Patients With End-Stage Renal Disease on Maintenance Hemodialysis: A Cross-Sectional Study.

BACKGROUND

Cardiovascular disease is the leading cause of mortality in end-stage renal disease (ESRD), with left ventricular dysfunction (LVD) as its most consequential manifestation. Despite the well-established role of disturbed mineral metabolism in uremic cardiomyopathy, the calcium-phosphate (Ca×PO₄) product is widely used as a composite risk marker in ESRD management. This study aimed to determine the prevalence of LVD in ESRD patients on maintenance hemodialysis and to evaluate albumin-corrected calcium, Ca×PO₄ product, serum albumin, hemoglobin, and uric acid as cross-sectional correlates of left ventricular ejection fraction (LVEF). Sixty consecutive ESRD patients on stable thrice-weekly hemodialysis underwent predialysis transthoracic echocardiography, and LVD was defined as LVEF <50%. Total serum calcium was corrected for albumin using the Payne formula.

RESULTS

LVD was present in 58.3% of patients (35/60); 35.0% met criteria for heart failure with reduced ejection fraction (LVEF <40%) and 23.3% for heart failure with mildly reduced ejection fraction (40%-49%). Among all biochemical parameters evaluated, albumin-corrected calcium was the sole independent associate of LVD on multivariate analysis (adjusted OR, 5.83; 95% CI, 1.84-18.42; p = 0.003), although causal inference is precluded by the cross-sectional design. Serum albumin demonstrated the strongest univariate biochemical correlation with LVEF (Spearman r = 0.701, p <0.001), exceeding corrected calcium (r = -0.488, p <0.001). The Ca×PO₄ product, in both uncorrected (r = -0.121, p = 0.358) and corrected form (r = -0.129, p = 0.329), did not predict LVD. Hemoglobin and uric acid similarly showed no significant association with LVEF. E/e' ratio was the strongest echocardiographic correlate of LVEF (r = -0.566, p <0.001) and was significantly elevated in the LVD group (median 13.9 vs. 10.8; p = 0.001).

CONCLUSIONS

LVD is highly prevalent in ESRD patients on maintenance hemodialysis. Ca×PO₄ product does not show significant cross-sectional association with left ventricular systolic dysfunction in either corrected or uncorrected form. Albumin-corrected calcium was a key independent biochemical correlate of LVD in this cohort, while serum albumin emerged as an additional strong cardiac risk correlate warranting prospective evaluation. However, longitudinal studies are needed to determine whether these associations are causal and to inform clinical practice.