Serum 25-Hydroxyvitamin D Concentration Spectrum in Patients with Sickle Cell Disease: A Cross-Sectional Descriptive Study

Abstract

Background: Low serum 25-hydroxyvitamin D [25(OH)D] concentrations are frequently reported in sickle cell disease (SCD), but prevalence estimates alone can obscure the depth and shape of the concentration distribution. Objective: To characterize the serum 25(OH)D concentration spectrum in patients with SCD using vitamin D measurements alone. Materials and Methods: A cross-sectional analysis was performed on 54 vitamin D measurements available in an institutional research database. Only the vitamin D variable was analyzed. Descriptive statistics and conventional concentration strata were used. Results: Mean 25(OH)D was 15.98 ± 8.62 ng/mL and median concentration was 14.40 ng/mL (range, 4.5–32.0 ng/mL). Thirty-four measurements (63.0%) were below 20 ng/mL, including 17 (31.5%) below 10 ng/mL. Sixteen (29.6%) were 20–29.9 ng/mL and only four (7.4%) were ≥30 ng/mL. Conclusion: The dataset demonstrates a pronounced lower-end shift in serum 25(OH)D concentrations. Reporting the complete concentration spectrum may be more informative than a binary deficient/non-deficient label. Longitudinal multicenter studies are needed to determine whether the depth and persistence of low 25(OH)D concentrations have clinical significance.