Table 4. Mean (± SEM) Age and Clinical Status of Boys and Girls With Sickle Cell Disease Independent of Vitamin A Status

Variable	Boys (n = 34)	Girls (n = 25)
Age, years	6.62 ± 0.71	7.63 ± 1.01
Plasma retinol, μg/dL	49.8 ± 4.90	68.1 ± 5.1^{^a}
Weight, kg	25.78 ± 2.65	25.64 ± 3.26
Weight percentile	34.05 ± 5.59	39.7 ± 6.60
Height, cm	121.32 ± 4.76	119.86 ± 7.27
Height percentile	35.76 ± 5.95	41.66 ± 6.65
Pain crises	0.72 ± 0.16	1.00 ± 0.38
Units of blood	0.91 ± 0.37	1.41 ± 0.49
Infections	0.66 ± 0.16	0.50 ± 0.18
Hospitalizations	1.43 ± 0.33	1.57 ± 0.47
Hematocrit, %	26.98 ± 0.93	28.48 ± 0.87
Hemoglobin, g/dL	8.58 ± 0.32	9.00 ± 0.36
White blood cells × 10⁶/mL	13.30 ± 0.84	11.72 ± 1.06
C-reactive protein, mg/L	8.85 ± 0.39	4.444 ± 1.2
Alpha-1-acid glycoprotein, g/L	0.689 ± 0.06	0.689 ± 0.05
Retinol binding protein, mg/L	21.02 ± 1.52	21.63 ± 1.64
Tumor necrosis factor alpha, pg/mL	59.4 ± 17.89	32.55 ± 14.04
Inflammation score	0.412 ± 0.12	0.36 ± 0.098
Health score^{^b}	3.82 ± 0.65	4.35 ± 1.05

↵^a P < 0.05; girls had higher mean plasma retinol concentrations than boys.
↵^b Health score is the sum of the number of episodes of pain crisis, infection, hospital admission, and/or blood units received.