PD

NP

OR

95% CI

p-value

Age at diagnosis

≤5 years

109

155

0.9

0.5 - 1.6

0.7734

>5 years*

39

41

1.1

0.6 - 1.9

Number of hospitalizations/year

> 5

39

25

2.4

1.4 - 4.3

0.0013

≤5*

109

171

Number of bone CVO/year

> 3

61

41

2.7

1.6 - 4.3

0.0000

≤3*

87

155

Blood transfusion

Yes

147

176

16.7

2.2 - 125.9

0.0002

No*

1

20

Age of first transfusion

≤12 months

14

12

1.4

0.6 - 3.2

0.3734

>12 months*

133

164

Number of transfusions since discovery

>5

37

26

2.03

1.2 - 3.6

0.0127

≤5*

110

150