Chronic and acute anemia and extracranial internal carotid stenosis are risk factors for silent cerebral infarcts in sickle cell anemia

• Published in: Blood Vol. 125; no. 10; pp. 1653 - 1661
• Main Authors: Bernaudin, Françoise, Verlhac, Suzanne, Arnaud, Cécile, Kamdem, Annie, Vasile, Manuela, Kasbi, Florence, Hau, Isabelle, Madhi, Fouad, Fourmaux, Christine, Biscardi, Sandra, Epaud, Ralph, Pondarré, Corinne
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 05.03.2015
• Subjects: Acute Disease; Adolescent; Anemia - blood; Anemia - complications; Anemia, Sickle Cell - blood; Anemia, Sickle Cell - complications; Anemia, Sickle Cell - genetics; Blood Flow Velocity; Carotid Artery, Internal; Carotid Stenosis - complications; Carotid Stenosis - diagnosis; Carotid Stenosis - physiopathology; Cerebral Infarction - diagnosis; Cerebral Infarction - etiology; Child; Child, Preschool; Chronic Disease; Cohort Studies; Female; Humans; Infant; Infant, Newborn; Longitudinal Studies; Magnetic Resonance Angiography; Magnetic Resonance Imaging; Male; Risk Factors; Young Adult
• ISSN: 0006-4971; 1528-0020; 1528-0020
• DOI: 10.1182/blood-2014-09-599852

Early transcranial Doppler (TCD) screening of the Créteil sickle cell anemia (SCA)-newborn cohort, and rapid initiation of transfusion programs, resulted in successful prevention of overt strokes, but a high cumulative risk of silent cerebral infarcts (SCI) remained, suggesting that TCD screening does not identify all patients with SCA at risk for SCI. We hypothesized that episodes of hypoperfusion/hypoxia, as observed during acute chest syndromes or acute anemic events (AAE), and extracranial internal carotid artery (eICA) stenoses, detectable via submandibular Doppler sonography and cervical magnetic resonance angiography (MRA), could also be risk factors for SCI. This study includes 189 stroke-free patients with SCA from the Créteil newborn cohort (1992-2010) followed longitudinally by magnetic resonance imaging/MRA, including cervical MRA at the last assessment. All patients with abnormal TCD and/or intracranial stenoses were placed on a transfusion program. Mean follow-up was 9.9 years (range, 2.2-19.9 years; 1844 patient-years). Annual rates of clinical events were calculated. The cumulative risk for SCI was 39.1% (95% confidence interval [CI], 23.5%-54.7%) by age 18 years, with no plateau. We confirm that baseline hemoglobin level lower than 7 g/dL before age 3 years is a highly significant predictive risk factor for SCI (hazard ratio, 2.97; 95% CI, 1.43-6.17; P = .004). Furthermore, we show that AAE rate (odds ratio, 2.64 per unit increase; 95% CI, 1.09-6.38; P = .031) and isolated eICA stenosis (odds ratio, 3.19; 95% CI, 1.18-8.70; P = .023) are significant and independent risk factors for SCI. •Baseline hemoglobin levels lower than 7 g/dL, acute anemia, and extracranial internal carotid stenosis are significant and independent risk factors for SCI in SCA.