Relationship of Baseline Hemoglobin Level with Serum Ferritin, Postphlebotomy Hemoglobin Changes, and Phlebotomy Requirements among HFE C282Y Homozygotes
Table 3
Comparisons of mean ± SD decreases (95% confidence interval), percentage changes in posttreatment hemoglobin from baseline, and the mean ± SD number of phlebotomies among hemoglobin subgroups of C282Y homozygotes and male genotype groups.
Base-Hb
Post-Hb
MD (95% CI)
% change
Post < Base
Nr-PH
g/L
g/L
g/L
g/L
(%)
Mean ± SD
Males
C282Y/C282Y
150.4 ± 10.1
144.4 ± 11.0
−6.0 (−7.7, −4.4)
−4.0
93/124 (75)
21.7 ± 14.8
SF <1000 μg/L
151.9 ± 8.4
145.3 ± 10.7
−6.6 (−8.7, −4.5)
−4.2
65/85 (76)
16.0 ± 6.8
SF >1000 μg/L
147.1 ± 12.6
142.2 ± 11.4
−4.8 (−7.7, −1.9)
−3.3
28/39 (72)
34.0 ± 19.4
value
0.014
0.31
<0.001
Low SF/high Hb
157.4 ± 4.7
149.0 ± 10.9
−8.4 (−11.4, −5.5)
−5.3
43/52 (83)
14.3 ± 5.1
Low SF/low Hb
143.3 ± 4.9
139.6 ± 7.5
−3.7 (−6.2, −1.2)
−2.6
22/33 (67)
18.8 ± 8.1
value
<0.001
0.038
0.038
High SF/high Hb
160.3 ± 5.6
151.2 ± 9.4
−9.1 (−14, −4.3)
−5.7
13/16 (81)
26.7 ± 11.3
High SF/low Hb
137.8 ± 6.2
136.0 ± 8.1
−1.8 (−5.1, −1.5)
−1.3
15/23 (65)
39.1 ± 22.2
value
<0.001
0.014
0.06
C282Y/H63D
153.2 ± 6.7
143.4 ± 9.6
−9.9 (−15, −4.9)
−6.5
15/18 (83)
11.2 ± 4.9
Females
C282Y/C282Y
138.2 ± 8.1
133.1 ± 9.1
−5.1 (−7.3, −3.0)
−3.7
52/72 (72)
15.4 ± 10.9
SF <1000 μg/L
139.0 ± 8.1
133.2 ± 9.1
−5.8 (−8.0, −3.6)
−4.2
47/61 (77)
12.3 ± 6.3
SF >1000 μg/L
134.0 ± 6.6
132.5 ± 9.8
−1.5 (−8.5, 5.6)
−1.1
5/11 (45)
32.7 ± 14.7
value
0.059
0.16
<0.001
Low SF/high Hb
144.3 ± 5.1
136.3 ± 7.7
−8.0 (−10.5, −5.5)
−5.5
31/35 (89)
12.5 ± 7.5
Low SF/low Hb
131.2 ± 5.3
128.9 ± 9.2
−2.8 (−6.7, −1.0)
−2.1
16/26 (62)
12.0 ± 4.1
value
0.020
0.64
High SF/high Hb
142.0 ± 2.0
136.7 ± 3.2
−5.3 (−9.1, −1.5)
−3.7
3/3 (100)
20.7 ± 10.3
High SF/low Hb
131.0 ± 4.9
131.0 ± 11.2
0.0
0.0
2/8 (25)
37.3 ± 13.9
value
0.005
0.49
0.036
Results are mean ± SD. Base-Hb: baseline hemoglobin; Post-Hb: posttreatment hemoglobin; MD: mean difference between posttreatment hemoglobin and baseline hemoglobin; Post < Base: number (%) of patients with decreased posttreatment hemoglobin compared with baseline values; Nr-PH: number of phlebotomies. The percentage change is expressed as difference between posttreatment hemoglobin level and baseline hemoglobin level divided by baseline hemoglobin level × 100 and was used as a continuous variable for calculations of the statistical differences between subgroups.