title: Familial [corrected] transmission of coronary heart disease: a cohort study of 80,214 Swedish adoptees linked to their biological and adoptive parents.
abstract: BACKGROUND
  Studies of adoptees have the potential to disentangle the contributions of genetic versus family environmental factors in the familial [corrected] transmission of coronary heart disease (CHD) because adoptees do not share the same family environment as their biological parents. The aims of this study were as follows: (1) to examine the risk of CHD in adopted men and women with at least one biological parent with CHD and (2) to examine the risk of CHD in adopted men and women with at least one adoptive parent with CHD.
  
  
  METHODS
  The Swedish Multigenerational register was used to follow all Swedish-born adoptees (born in or after 1932, n = 80,214) between January 1, 1973, and December 31, 2008, for CHD. The risk of CHD was estimated in adopted men and women with at least one biological parent with CHD and adopted men and women with at least one adoptive parent with CHD. The control groups consisted of adopted men or women without a biological parent with CHD or adopted men or women without an adoptive parent with CHD.
  
  
  RESULTS
  Adopted men and women with at least one biological parent with CHD (n = 749) were 1.4 to 1.6 times (statistically significant, 95% CI) more likely to have CHD than adoptees without a biological parent with CHD. In contrast, men and women with at least one adoptive parent with CHD (n = 1,009) were not at increased risk of the disease.
  
  
  CONCLUSIONS
  These findings (based on validated hospital diagnoses unbiased by recall) suggest that the familial [corrected] transmission of CHD from parents to offspring is more related to genetic factors than to family environmental factors.
authors.affiliation: Center for Primary Health Care Research, Lund University, Malmö, Sweden. Kristina.sundquist@med.lu.se
authors.forename: Kristina
authors.initials: K
authors.lastname: Sundquist
authors.forename: Marilyn
authors.initials: M
authors.lastname: Winkleby
authors.forename: Xinjun
authors.initials: X
authors.lastname: Li
authors.forename: Jianguang
authors.initials: J
authors.lastname: Ji
authors.forename: Kari
authors.initials: K
authors.lastname: Hemminki
authors.forename: Jan
authors.initials: J
authors.lastname: Sundquist
mesh_terms: D000300:Adoption; D003324:Coronary Artery Disease / Q000453:epidemiology / Q000235:genetics*; D005260:Female; D005500:Follow-Up Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D009017:Morbidity / Q000639:trends; D016487:Parenting; D010290:Parents; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology