title: Depression and obesity: do shared genes explain the relationship?
abstract: BACKGROUND
  Studies have found a modest association between depression and obesity, especially in women. Given the substantial genetic contribution to both depression and obesity, we sought to determine whether shared genetic influences are responsible for the association between these two conditions.
  
  
  METHODS
  Data were obtained from 712 monozygotic and 281 dizygotic female twin pairs who are members of the community-based University of Washington Twin Registry. The presence of depression was determined by self-report of doctor-diagnosed depression. Obesity was defined as body mass index of > or =30 kg/m(2), based on self-reported height and weight. Generalized estimating regression models were used to assess the age-adjusted association between depression and obesity. Univariate and bivariate structural equation models estimated the components of variance attributable to genetic and environmental influences.
  
  
  RESULTS
  We found a modest phenotypic association between depression and obesity (odds ratio=1.6, 95% confidence interval=1.2-2.1). Additive genetic effects contributed substantially to depression (57%) and obesity (81%). The best-fitting bivariate model indicated that 12% of the genetic component of depression is shared with obesity.
  
  
  CONCLUSIONS
  The association between depression and obesity in women may be in part due to shared genetic risk for both conditions. Future studies should examine the genetic, environmental, social, and cultural mechanisms underlying the relationship between this association.
authors.affiliation: Department of Psychiatry, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0738, USA. nafari@ucsd.edu
authors.forename: Niloofar
authors.initials: N
authors.lastname: Afari
authors.forename: Carolyn
authors.initials: C
authors.lastname: Noonan
authors.forename: Jack
authors.initials: J
authors.lastname: Goldberg
authors.forename: Peter
authors.initials: P
authors.lastname: Roy-Byrne
authors.forename: Ellen
authors.initials: E
authors.lastname: Schur
authors.forename: Golnaz
authors.initials: G
authors.lastname: Golnari
authors.forename: Dedra
authors.initials: D
authors.lastname: Buchwald
mesh_terms: D000328:Adult; D015992:Body Mass Index; D003863:Depression / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D016015:Logistic Models; D008875:Middle Aged; D008957:Models, Genetic; D009765:Obesity / Q000235:genetics*; D010641:Phenotype; D012042:Registries; D012307:Risk Factors; D014429:Twins, Dizygotic / Q000235:genetics*; D014430:Twins, Monozygotic / Q000235:genetics*; D014861:Washington; D055815:Young Adult
references.citation: Twin Res Hum Genet. 2006 Dec;9(6):1023-9
references.pmid: 17254446
references.citation: Science. 2007 May 11;316(5826):889-94
references.pmid: 17434869
references.citation: Obesity (Silver Spring). 2008 Feb;16(2):473-5
references.pmid: 18239662
references.citation: Biol Psychiatry. 2003 Aug 1;54(3):330-7
references.pmid: 12893108
references.citation: Diabetes Care. 2001 Jun;24(6):1069-78
references.pmid: 11375373
references.citation: Ciba Found Symp. 1996;201:108-15; discussion 115-7, 188-93
references.pmid: 9017277
references.citation: Am J Med Sci. 2006 Apr;331(4):166-74
references.pmid: 16617231
references.citation: Ann Endocrinol (Paris). 2000 Dec;61 Suppl 6:24-30
references.pmid: 11148333
references.citation: Handb Exp Pharmacol. 2006;(175):485-524
references.pmid: 16722247
references.citation: Clin Genet. 1983 Aug;24(2):103-12
references.pmid: 6577993
references.citation: J Health Psychol. 2008 Nov;13(8):1190-7
references.pmid: 18987092
references.citation: J Psychosom Res. 2006 Mar;60(3):263-71
references.pmid: 16516658
references.citation: Science. 1996 Nov 29;274(5292):1527-31
references.pmid: 8929413
references.citation: Annu Rev Med. 2003;54:453-71
references.pmid: 12414915
references.citation: Am J Public Health. 1983 Feb;73(2):171-8
references.pmid: 6600376
references.citation: PLoS Genet. 2007 Jul;3(7):e115
references.pmid: 17658951
references.citation: JAMA. 2002 Oct 9;288(14):1723-7
references.pmid: 12365955
references.citation: Am J Psychiatry. 2000 Oct;157(10):1552-62
references.pmid: 11007705
references.citation: Psychiatr Genet. 2009 Feb;19(1):32-8
references.pmid: 19125106
references.citation: Int J Obes (Lond). 2008 Jun;32(6):881-91
references.pmid: 18414420
references.citation: Gen Hosp Psychiatry. 2008 Mar-Apr;30(2):127-37
references.pmid: 18291294
references.citation: Pediatrics. 2001 May;107(5):1049-56
references.pmid: 11331685
references.citation: Neuropsychopharmacology. 2006 Mar;31(3):620-7
references.pmid: 16192984
references.citation: Acta Genet Med Gemellol (Roma). 1979;28(3):225-36
references.pmid: 297423
references.citation: Gen Hosp Psychiatry. 2008 Jan-Feb;30(1):32-9
references.pmid: 18164938
references.citation: Int J Obes Relat Metab Disord. 2004 Mar;28(3):442-6
references.pmid: 14724656
references.citation: Am J Psychiatry. 2006 Jan;163(1):109-14
references.pmid: 16390897
references.citation: Nature. 2000 Apr 6;404(6778):644-51
references.pmid: 10766251
references.citation: Am J Med Genet B Neuropsychiatr Genet. 2003 Jan 1;116B(1):103-25
references.pmid: 12497624
references.citation: BMC Med Res Methodol. 2007 Apr 30;7:17
references.pmid: 17470289
references.citation: Arch Intern Med. 2001 Jul 23;161(14):1725-30
references.pmid: 11485505
references.citation: Science. 2003 Jul 18;301(5631):386-9
references.pmid: 12869766
references.citation: Am J Geriatr Psychiatry. 2007 Sep;15(9):815-25
references.pmid: 17804833
references.citation: Eur J Neurol. 2001 Jul;8(4):315-9
references.pmid: 11422427
references.citation: Biol Psychiatry. 2007 Jan 15;61(2):223-30
references.pmid: 16806099
references.citation: Prev Chronic Dis. 2009 Jan;6(1):A10
references.pmid: 19080016
references.citation: J Am Geriatr Soc. 2001 Jun;49(6):732-6
references.pmid: 11454111
references.citation: Nat Genet. 2009 Jan;41(1):25-34
references.pmid: 19079261
references.citation: Biol Psychiatry. 1998 Aug 1;44(3):151-62
references.pmid: 9693387
references.citation: Brain Behav Immun. 2005 Jul;19(4):275-80
references.pmid: 15944067
references.citation: Mol Psychiatry. 2001 Sep;6(5):579-85
references.pmid: 11526472
references.citation: J Psychosom Res. 1996 Jan;40(1):59-66
references.pmid: 8730645
references.citation: Am J Geriatr Psychiatry. 1999 Spring;7(2):124-31
references.pmid: 10322239
references.citation: Soc Sci Med. 2007 Dec;65(12):2458-63
references.pmid: 17761378
references.citation: Biol Psychiatry. 2005 May 1;57(9):999-1003
references.pmid: 15860340
references.citation: Obesity (Silver Spring). 2006 Apr;14(4):529-644
references.pmid: 16741264
references.citation: Arch Gen Psychiatry. 1994 Jan;51(1):8-19
references.pmid: 8279933
references.citation: Obes Res. 2003 Jun;11(6):802-8
references.pmid: 12805402
references.citation: Epidemiol Rev. 2007;29:49-61
references.pmid: 17566051
references.citation: Obes Res. 2002 Jul;10(7):585-9
references.pmid: 12105278
references.citation: Arch Intern Med. 2000 Jun 26;160(12):1761-8
references.pmid: 10871968
references.citation: Ann Epidemiol. 2008 Jun;18(6):458-66
references.pmid: 18329894
references.citation: Arch Pediatr Adolesc Med. 2000 Sep;154(9):931-5
references.pmid: 10980798
references.citation: Mol Psychiatry. 2008 Aug;13(8):772-85
references.pmid: 17938638
references.citation: Curr Opin Lipidol. 2008 Apr;19(2):113-21
references.pmid: 18388690
references.citation: Eat Weight Disord. 1998 Jun;3(2):71-7
references.pmid: 10728153
references.citation: J Psychosom Res. 1980;24(5):233-41
references.pmid: 7205712
references.citation: Mol Psychiatry. 2006 Oct;11(10):892-902
references.pmid: 16880826
references.citation: Am J Public Health. 2000 Feb;90(2):251-7
references.pmid: 10667187
references.citation: J Affect Disord. 1993 Oct-Nov;29(2-3):85-96
references.pmid: 8300981
references.citation: J Psychosom Res. 1981;25(2):75-82
references.pmid: 7277275
references.citation: Obes Res. 1998 Sep;6 Suppl 2:51S-209S
references.pmid: 9813653
references.citation: Ann Behav Med. 2006 Aug;32(1):68-76
references.pmid: 16827631
references.citation: Psychol Bull. 1995 Jan;117(1):3-20
references.pmid: 7870862
references.citation: Int J Obes Relat Metab Disord. 1992 Dec;16(12):999-1003
references.pmid: 1335980
references.citation: Arch Gen Psychiatry. 2006 Jul;63(7):824-30
references.pmid: 16818872
references.citation: Twin Res Hum Genet. 2005 Aug;8(4):362-7
references.pmid: 16176721
references.citation: Br Med J. 1976 Jan 3;1(6000):7-9
references.pmid: 1247732
references.citation: Int J Obes (Lond). 2008 Mar;32(3):558-66
references.pmid: 17895885
references.citation: Nat Genet. 2009 Jan;41(1):18-24
references.pmid: 19079260
references.citation: J Psychol. 1989 Jul;123(4):385-95
references.pmid: 2795495
references.citation: Clin Genet. 1989 Jun;35(6):423-32
references.pmid: 2736790
references.citation: Int J Obes Relat Metab Disord. 2003 Apr;27(4):514-21
references.pmid: 12664085
references.citation: Neurosci Lett. 2007 Mar 6;414(2):155-8
references.pmid: 17258395
references.citation: Am J Epidemiol. 2003 Dec 15;158(12):1139-47
references.pmid: 14652298
references.citation: Gen Hosp Psychiatry. 2007 Mar-Apr;29(2):147-55
references.pmid: 17336664
references.citation: Am J Epidemiol. 2000 Jul 15;152(2):163-70
references.pmid: 10909953