Cardiovascular complications represent the main determinant of survival in patients with hemoglobinopathies. Serum cystatin C is a well-known marker of nephropathy in sickle cell disease (SCD) and β-thalassemia patients that has recently emerged as a strong predictor of cardiovascular dysfunction in patients with and without kidney disease. We performed a case control study to determine the role of cystatin C as a predictor of subclinical cardiovascular dysfunction in SCD and β-thalassemia patients. We enrolled 40 SCD patients with a mean age of 12.4 years, 40 β-thalassemia patients with a mean age of 11.4 years and 40 age and sex-matched controls. We assessed hematological profile, serum ferritin, urinary albumin-creatinine ratio (UACR), serum cystatin C, echocardiography and carotid intima media thickness (CIMT). UACR, cystatin C and CIMT were higher in SCD and β-thalassemia patients compared to controls (p < .001). Significantly higher cystatin C levels were observed in SCD and β-thalassemia patients with nephropathy or left ventricular systolic dysfunction (shortening fraction <30%, or ejection fraction <55%; p < .001). Moreover, SCD patients with pulmonary hypertension had significantly higher cystatin C levels. Cystatin C levels were positively correlated with CIMT in SCD (p = .02) and β-thalassemia patients (p < .001) while negatively correlated with ejection fraction and shortening fraction (p < .001). The cutoff values of cystatin C ≥ 16.03 and ≥ 13.2 (ng/mL) could detect subclinical cardiac dysfunction risk among SCD and β-thalassemia patients respectively. Cystatin C appears to be a promising marker for subclinical cardiovascular dysfunction in SCD and β-thalassemia patients.
Keywords: Cardiovascular; cystatin C; nephropathy; sickle cell disease; β-thalassemia.