title: Alpha thalassemia and stroke risk in sickle cell anemia.
abstract: In an effort to identify possible risk factors for stroke in Sickle Cell Anemia (Hb SS), we analyzed the distribution of alpha-globin gene deletions in a group of Hb SS patients with and without stroke. The group with stroke consisted of 44 patients, (27 male, 17 female) with a mean of 7.5 years at time of stroke. The control group (non-stroke) had 256 Hb SS patients (126 male, 130 female) with a mean age of 7.7 years. There were 9 patients with heterozygous alpha-thalassemia in the stroke group (20.5%). In the control group, there were 93 patients with heterozygous alpha-thalassemia and 5 with homozygous alpha-thalassemia. The incidence of alpha-thalassemia in Hb SS patients without stroke (38%) was comparable to that reported for the African-American population in general. The incidence in the stroke population (20.5%) was significantly lower (P = 0.02) These results indicate that alpha-thalassemia is associated with a lower risk of stroke in Hb SS. This observation should be confirmed in studies involving larger numbers of patients. Possible protective effects of alpha-thalassemia are unknown but may be related to decreased hemolysis and more favorable rheologic properties of red blood cells.
authors.affiliation: Department of Neurology, Medical College of Georgia, Augusta 30912.
authors.forename: R J
authors.initials: RJ
authors.lastname: Adams
authors.forename: A
authors.initials: A
authors.lastname: Kutlar
authors.forename: V
authors.initials: V
authors.lastname: McKie
authors.forename: E
authors.initials: E
authors.lastname: Carl
authors.forename: F T
authors.initials: FT
authors.lastname: Nichols
authors.forename: J C
authors.initials: JC
authors.lastname: Liu
authors.forename: K
authors.initials: K
authors.lastname: McKie
authors.forename: A
authors.initials: A
authors.lastname: Clary
mesh_terms: D000293:Adolescent; D000328:Adult; D000755:Anemia, Sickle Cell / Q000150:complications* / Q000235:genetics; D044383:Black People / Q000235:genetics; D002561:Cerebrovascular Disorders / Q000453:epidemiology* / Q000209:etiology / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D005260:Female; D017353:Gene Deletion; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D007223:Infant; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D017085:alpha-Thalassemia / Q000453:epidemiology* / Q000209:etiology / Q000235:genetics; D001741:Black or African American