Familial clustering of chronic obstructive pulmonary disease (COPD) is well established, but the familial risk of COPD has not been determined among adoptees. The aim was to determine whether the familial transmission of COPD is related to disease in biological and/or adoptive parents.
Historic cohort study.
80,214 (50% females).
The Swedish Multi-Generation Register was used to follow all Swedish-born adoptees born in 1932-2004 (n=80,214) between 1 January 1964 and 31 December 2010 for COPD (n=1978). The risk of COPD was estimated in adoptees with at least one biological parent with COPD but no adoptive parent with COPD (n=162) compared with adoptees without a biological or adoptive parent with COPD. The risk of COPD was also determined in adoptees with at least one adoptive parent but no biological parent with COPD (n=110), and in adoptees with both affected biological and adoptive parents (n=162).
COPD in adoptees.
Adoptees with COPD in at least one biological parent but no adoptive parent were more likely to have COPD than adoptees without a biological or adoptive parent with COPD (standardised incidence ratio, SIR=1.98 (95% CI 1.69 to 2.31)). The familial SIR for adoptees with both a biological parent and an adoptive parent with COPD was 1.68 (95% CI 1.39 to 2.00). Adoptees with at least one adoptive parent with COPD but no biological parent with COPD were not at an increased risk of COPD (SIR=1.12 (95% CI 0.92 to 1.35)).
The findings of the study show that the familial transmission of COPD is associated with COPD in biological but not adoptive parents, suggesting that genetic or early life factors are important in the familial transmission of COPD.
Notes
Cites: Epidemiology. 1990 Jan;1(1):43-62081237
Cites: Respir Med. 2004 Mar;98(3):263-7015002763
Cites: COPD. 2005 Sep;2(3):331-917146998
Cites: Am J Respir Crit Care Med. 2007 Sep 15;176(6):532-5517507545
Cites: Am J Respir Crit Care Med. 2008 Mar 1;177(5):486-9018048810
Cites: J Epidemiol Community Health. 2008 May;62(5):398-40118413451
Cites: Cancer Epidemiol Biomarkers Prev. 2001 Jul;10(7):733-4111440958
Cites: Am J Respir Crit Care Med. 2014 Nov 1;190(9):989-9525192554
Cites: Int J Epidemiol. 1982 Dec;11(4):378-866984028
Cites: IARC Sci Publ. 1987;(82):1-4063329634
Cites: Nature. 2009 Oct 8;461(7265):747-5319812666