Transcranial doppler as screening method for sickling crises in children with sickle cell anemia: a latin America cohort study

Table 4 Univariate Survival Analyses using a Proportional Hazard Frailty Model for Vaso-occlusive Syndrome Outcome

Predictor Variable	HR	CI 95%	P
Doppler TAMMV conclusion
Normal	-	-	-
Intermediate	1.97	0.64—6.07	0.24
Altered	0.89	0.09—8.84	0.92
Doppler TAMMV conclusion
Normal	-	-	-
Intermediate or altered	1.67	0.60—4.78	0.33
TAMMV Doppler (continuous variable)	1.01	1.00—1.02	0.06
Pulsatility index	0.21	0.01—4.71	0.33
Doppler PSV (cm/s) MCA	1.01	1.00—1.02	0.04
Doppler EDV (cm/s) MCA	1.02	1.01—1.04	0.01
Doppler TAMMV (cm/s) BA	1.02	1.00—1.04	0.04
Sex	0.73	0.26—2.05	0.55
Age	0.98	0.90—1.08	0.74
Genotype
SS	-	-	-
Sβ ou Sα	0.27	0.09—0.83	0.02
FS	0.14	0.03—0.64	0.01
SC	0.01	0.16—2.31	0.47
Hydroxyurea	1.77	0.82—3.83	0.15
Prophylactic transfusion	1.04	0.27—4.05	0.95
Hb	0.49	0.38 —0.65	< 0.001
Ht	0.78	0.71—0.85	< 0.001
Leukocytes	1.1	1.05—1.15	< 0.001
Platelets	0.997	0.994—0.999	0.02
Reticulocytes	1.14	1.06—1.23	< 0.001

TAMMV Time average mean maximum velocity, MCA Middle cerebral artery, PSV Peak systolic velocities, EDV End-diastolic velocity, BA Basilar artery, Hb Hemoglobin, Ht Hematocrit; SS: Homozygous for HbS; Sβ: Heterozygosity for HbS and beta thalassemia; SC: Heterozygosity for HbS and HbC; FS: Heterozygosis for HbS and persistence of fetal hemoglobin; Sα: Heterozygosity for HbS and alpha thalassemia

ISSN: 1471-2431