Objective: The objective of this study was to determine the relation of plasma zinc (Zn) status to growth and maturation in children with SS genotype sickle cell disease.
Study design: A cross-sectional study of 104 subjects who were 50% female and ranged in age from 0.4 to 18 years was performed. Measures included plasma Zn concentration (Znp), height, weight, skinfold thicknesses, elbow breadth, upper arm muscle area, and fat-free mass and fat mass by total body electrical conductivity. Skeletal maturation was assessed by hand-wrist x-ray evaluation and sexual maturation by Tanner stage.
Results: A total of 44% of the patients had low Znp (<10.7 micromol/L [70 microg/dl]); those with low Znp had significantly lower SD scores for height (p = 0.003), weight (p = 0.003), upper arm muscle area (p = 0.045), fat-free mass (p = 0.025), and elbow breadth (p = 0.017) and greater skeletal maturation delay (p = 0.04). In older children (>9 years) low Znp was associated with decreased Tanner scores for pubic hair (p = 0.001) and breast and genital maturation (p = 0.009). No significant differences were seen in age, sex, or fat stores according to Zn status.
Conclusions: Decreased plasma Zn is common in children with SS genotype sickle cell disease and is associated with decreased linear growth, skeletal growth, muscle mass, and sexual and skeletal maturation.