title: Male pattern baldness and its association with coronary heart disease: a meta-analysis.
abstract: OBJECTIVE
  To confirm the association between male pattern baldness and coronary heart disease (CHD).
  
  
  METHODS
  Meta-analysis of observational studies.
  
  
  METHODS
  Medline and the Cochrane Library were searched for articles published up to November 2012 using keywords that included both 'baldness' and 'coronary heart disease' and the reference lists of those studies identified were also searched.
  
  
  METHODS
  Observational studies were identified that reported risk estimates for CHD related to baldness. Two observers independently assessed eligibility, extracted data and assessed the possibility of bias.
  
  
  RESULTS
  The adjusted relative risk (RR) and 95% CI were estimated using the DerSimonian-Laird random-effect model.
  
  
  RESULTS
  850 possible studies, 3 cohort studies and 3 case-control studies were selected (36 990 participants). In the cohort studies, the adjusted RR of men with severe baldness for CHD was 1.32 (95% CI 1.08 to 1.63, p=0.008, I(2)=25%) compared to those without baldness. Analysis of younger men (<55 or ≤60 years) showed a similar association of CHD with severe baldness (RR 1.44, 95% CI 1.11 to 1.86, p=0.006, I(2)=0%). In three studies employing the modified Hamilton scale, vertex baldness was associated with CHD and the relation depended on the severity of baldness (severe vertex: RR 1.48 (1.04 to 2.11, p=0.03); moderate vertex: RR 1.36 (1.16 to 1.58, p<0.001); mild vertex: RR 1.18 (1.04 to 1.35, p<0.001)). However, frontal baldness was not associated with CHD (RR 1.11 (0.92 to 1.32, p=0.28)).
  
  
  CONCLUSIONS
  Vertex baldness, but not frontal baldness, is associated with an increased risk of CHD. The association with CHD depends on the severity of vertex baldness and also exists among younger men. Thus, vertex baldness might be more closely related to atherosclerosis than frontal baldness, but the association between male pattern baldness and CHD deserves further investigation.
authors.affiliation: Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Tomohide
authors.initials: T
authors.lastname: Yamada
authors.forename: Kazuo
authors.initials: K
authors.lastname: Hara
authors.forename: Hitomi
authors.initials: H
authors.lastname: Umematsu
authors.forename: Takashi
authors.initials: T
authors.lastname: Kadowaki
references.citation: Control Clin Trials. 1986 Sep;7(3):177-88
references.pmid: 3802833
references.citation: Ann N Y Acad Sci. 1951 Mar;53(3):708-28
references.pmid: 14819896
references.citation: Actas Dermosifiliogr. 2010 Apr;101(3):248-56
references.pmid: 20398601
references.citation: J Steroid Biochem Mol Biol. 1994 Aug;50(3-4):169-74
references.pmid: 8049146
references.citation: Int J Cardiol. 1998 Dec 31;67(3):251-5
references.pmid: 9894707
references.citation: BMJ. 1997 Sep 13;315(7109):629-34
references.pmid: 9310563
references.citation: Am Heart J. 1995 Nov;130(5):1003-10
references.pmid: 7484729
references.citation: Am Fam Physician. 1999 Apr 15;59(8):2189-94, 2196
references.pmid: 10221304
references.citation: N Engl J Med. 1999 Sep 23;341(13):964-73
references.pmid: 10498493
references.citation: Lancet. 2006 May 27;367(9524):1747-57
references.pmid: 16731270
references.citation: J Cardiovasc Risk. 2001 Jun;8(3):147-51
references.pmid: 11455846
references.citation: South Med J. 1975 Nov;68(11):1359-65
references.pmid: 1188424
references.citation: Dermatology. 2007;214(2):125-9
references.pmid: 17341860
references.citation: Stat Med. 2002 Jun 15;21(11):1539-58
references.pmid: 12111919
references.citation: Circulation. 2003 Jan 28;107(3):363-9
references.pmid: 12551853
references.citation: Eur J Dermatol. 2007 May-Jun;17(3):220-2
references.pmid: 17478384
references.citation: JAMA. 2009 Apr 15;301(15):1547-55
references.pmid: 19366774
references.citation: Biometrics. 1994 Dec;50(4):1088-101
references.pmid: 7786990
references.citation: Therapie. 1995 Mar-Apr;50(2):145-50
references.pmid: 7631289
references.citation: Ann Intern Med. 2009 Aug 18;151(4):W65-94
references.pmid: 19622512
references.citation: J Am Acad Dermatol. 2006 May;54(5):903-6
references.pmid: 16635680
references.citation: Br J Dermatol. 2010 Aug;163(2):371-7
references.pmid: 20426781
references.citation: J Am Acad Dermatol. 2006 May;54(5):824-44
references.pmid: 16635664
references.citation: Arch Dermatol. 2001 Jul;137(7):943-7
references.pmid: 11453815
references.citation: JAMA. 1993 Feb 24;269(8):998-1003
references.pmid: 8429606
references.citation: Arch Intern Med. 2011 Jul 25;171(14):1260-8
references.pmid: 21606093
references.citation: Arch Intern Med. 2000 Jan 24;160(2):165-71
references.pmid: 10647754
references.citation: J Androl. 1997 Sep-Oct;18(5):495-500
references.pmid: 9349747
references.citation: J Clin Epidemiol. 2008 Apr;61(4):344-9
references.pmid: 18313558
references.citation: Eur J Dermatol. 2011 Jan-Feb;21(1):79-82
references.pmid: 21224180
references.citation: Arterioscler Thromb Vasc Biol. 1999 Apr;19(4):972-8
references.pmid: 10195925
references.citation: JAMA. 2000 Apr 19;283(15):2008-12
references.pmid: 10789670
references.citation: Lancet. 2000 Sep 30;356(9236):1165-6
references.pmid: 11030300
references.citation: Br J Dermatol. 2004 Feb;150(2):186-94
references.pmid: 14996087
references.citation: J Endocrinol. 1998 Jan;156(1):59-65
references.pmid: 9496234
references.citation: Am Heart J. 1986 Feb;111(2):383-90
references.pmid: 3946178
references.citation: Am J Epidemiol. 1996 Apr 1;143(7):651-7
references.pmid: 8651226
references.citation: Am J Epidemiol. 2008 Mar 15;167(6):676-83
references.pmid: 18208984