title: Coronary artery outcomes among children with Kawasaki disease in the United States and Japan.
abstract: OBJECTIVE
  It has been claimed that the aneurysm rate for Kawasaki disease (KD) patients in Japan is lower than in the U.S. However it has been difficult to compare coronary artery (CA) outcomes between the two countries because of different definitions for CA abnormalities. Therefore, we compared CA internal diameters between Japanese and U.S. KD patients using standard definitions and methods.
  
  
  METHODS
  We retrospectively reviewed CA outcomes in 1082 KD patients from 2 centers in the U.S. and 3 centers in Japan and compared Z-max scores (maximum internal diameter for the left anterior descending or right coronary artery expressed as standard deviation units from the mean (Z-score) normalized for body surface area) obtained within 12 weeks after onset and calculated using two different regression equations from Canada (Dallaire) and Japan (Fuse). We defined a Z-max of < 2.5 as normal and a Z-max of ≥ 10 as giant aneurysm.
  
  
  RESULTS
  The median Z-max for the U.S. and Japanese subjects was 1.9 and 2.3 SD units, respectively (p < 0.001). There was no significant difference in rates of patients with Z-max ≥ 5.0 between the countries. In a multivariable model adjusting for age, sex, and treatment response, being Japanese was still associated with a higher Z-max score.
  
  
  CONCLUSIONS
  Previously reported differences in aneurysm rates between Japan and the U.S. likely resulted from use of different definitions and nomenclature. Adoption of Z-scores as a standard for reporting CA internal diameters will allow meaningful comparisons among different countries and will facilitate international, collaborative clinical trials.
authors.affiliation: Department of Pediatrics, Rady Children's Hospital, University of California San Diego, School of Medicine, La Jolla, CA, United States.
authors.forename: Shohei
authors.initials: S
authors.lastname: Ogata
authors.forename: Adriana H
authors.initials: AH
authors.lastname: Tremoulet
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Sato
authors.forename: Kayla
authors.initials: K
authors.lastname: Ueda
authors.forename: Chisato
authors.initials: C
authors.lastname: Shimizu
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Sun
authors.forename: Sonia
authors.initials: S
authors.lastname: Jain
authors.forename: Laura
authors.initials: L
authors.lastname: Silverstein
authors.forename: Annette L
authors.initials: AL
authors.lastname: Baker
authors.forename: Noboru
authors.initials: N
authors.lastname: Tanaka
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Ogihara
authors.forename: Satoshi
authors.initials: S
authors.lastname: Ikehara
authors.forename: Shinichi
authors.initials: S
authors.lastname: Takatsuki
authors.forename: Naoko
authors.initials: N
authors.lastname: Sakamoto
authors.forename: Tohru
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Shigeto
authors.initials: S
authors.lastname: Fuse
authors.forename: Tomoyo
authors.initials: T
authors.lastname: Matsubara
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ishii
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Saji
authors.forename: Jane W
authors.initials: JW
authors.lastname: Newburger
authors.forename: Jane C
authors.initials: JC
authors.lastname: Burns
mesh_terms: D002675:Child, Preschool; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007223:Infant; D007564:Japan / Q000453:epidemiology; D008297:Male; D009080:Mucocutaneous Lymph Node Syndrome / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D012189:Retrospective Studies; D016896:Treatment Outcome; D014463:Ultrasonography; D014481:United States / Q000453:epidemiology
keywords: Coronary artery aneurysm; Echocardiography; Kawasaki disease; Vasculitis; Z score