title: Morbidity and mortality in Klinefelter syndrome (47,XXY).
abstract: Klinefelter syndrome (KS) (47,XXY) is the most common sex chromosome disorder in man and is a relatively common cause of male infertility and hypogonadism. The syndrome has been known since 1942, and many reports of different diseases associated with KS have been reported since that, but a more systematic knowledge about the long-term outcome was not described until the last decade, where nation-wide epidemiological studies were reported from Britain and Denmark. We here review the epidemiological data from two cohorts of patients with KS in Denmark and Britain, showing a significant increase in both mortality and morbidity from a variety of different causes. Mortality was increased by 50% (SMR 1.5 or HR 1.4) corresponding to a median loss of approximately 2 years. The risk of being admitted to hospital with any diagnosis was increased by 70%. The underlying reason for the poorer health in KS may be caused by interaction of genetic, hormonal and socio-economic factors.
  
  
  CONCLUSIONS
  Both morbidity and mortality are significantly increased in Klinefelter syndrome with a 50% increase in mortality risk and a 70% increase in risk of being admitted to hospital.
authors.affiliation: Department of Clinical Genetics, Vejle Hospital, Sygehus Lillebaelt, Denmark. anders.bojesen@dadlnet.dk
authors.forename: Anders
authors.initials: A
authors.lastname: Bojesen
authors.forename: Claus H
authors.initials: CH
authors.lastname: Gravholt
mesh_terms: D003718:Denmark / Q000453:epidemiology; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007713:Klinefelter Syndrome / Q000453:epidemiology* / Q000401:mortality; D008297:Male; D009017:Morbidity; D009369:Neoplasms / Q000453:epidemiology; D012306:Risk; D006113:United Kingdom / Q000453:epidemiology