title: F8 gene mutation type and inhibitor development in patients with severe hemophilia A: systematic review and meta-analysis.
abstract: This systematic review was designed to provide more precise effect estimates of inhibitor development for the various types of F8 gene mutations in patients with severe hemophilia A. The primary outcome was inhibitor development and the secondary outcome was high-titer-inhibitor development. A systematic literature search was performed to include cohort studies published in peer-reviewed journals with data on inhibitor incidences in the various F8 gene mutation types and a mutation detection rate of at least 80%. Pooled odds ratios (ORs) of inhibitor development for different types of F8 gene mutations were calculated with intron 22 inversion as the reference. Data were included from 30 studies on 5383 patients, including 1029 inhibitor patients. The inhibitor risk in large deletions and nonsense mutations was higher than in intron 22 inversions (pooled OR = 3.6, 95% confidence interval [95% CI], 2.3-5.7 and OR = 1.4, 95% CI, 1.1-1.8, respectively), the risk in intron 1 inversions and splice-site mutations was equal (pooled OR = 0.9; 95% CI, 0.6-1.5 and OR = 1.0; 95% CI, 0.6-1.5), and the risk in small deletions/insertions and missense mutations was lower (pooled OR = 0.5; 95% CI, 0.4-0.6 and OR = 0.3; 95% CI, 0.2-0.4, respectively). The relative risks for developing high titer inhibitors were similar.
authors.affiliation: Department of Pediatrics, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands. s.c.gouw@umcutrecht.nl
authors.forename: Samantha C
authors.initials: SC
authors.lastname: Gouw
authors.forename: H Marijke
authors.initials: HM
authors.lastname: van den Berg
authors.forename: Johannes
authors.initials: J
authors.lastname: Oldenburg
authors.forename: Jan
authors.initials: J
authors.lastname: Astermark
authors.forename: Philip G
authors.initials: PG
authors.lastname: de Groot
authors.forename: Maurizio
authors.initials: M
authors.lastname: Margaglione
authors.forename: Arthur R
authors.initials: AR
authors.lastname: Thompson
authors.forename: Waander
authors.initials: W
authors.lastname: van Heerde
authors.forename: Jorien
authors.initials: J
authors.lastname: Boekhorst
authors.forename: Connie H
authors.initials: CH
authors.lastname: Miller
authors.forename: Saskia
authors.initials: S
authors.lastname: le Cessie
authors.forename: Johanna G
authors.initials: JG
authors.lastname: van der Bom
mesh_terms: D057134:Antibodies, Neutralizing / Q000097:blood / Q000276:immunology*; D005169:Factor VIII / Q000235:genetics* / Q000276:immunology* / Q000627:therapeutic use; D006467:Hemophilia A / Q000188:drug therapy / Q000235:genetics*; D006801:Humans; D009154:Mutation
chemical_list: D057134:Antibodies, Neutralizing; C078147:F8 protein, human; D005169:Factor VIII