Objective To confirm the association between male pattern baldness and coronary heart disease (CHD).
Design Meta-analysis of observational studies.
Data sources 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.
Study selection 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.
Data synthesis 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, I2=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, I2=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.
This is an open-access article distributed under the terms of the Creative Commons Attribution Non-commercial License, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited, the use is non commercial and is otherwise in compliance with the license. See: http://creativecommons.org/licenses/by-nc/3.0/ and http://creativecommons.org/licenses/by-nc/3.0/legalcode
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.
This web only file has been produced by the BMJ Publishing Group from an electronic file supplied by the author(s) and has not been edited for content.
Files in this Data Supplement:
- Data supplement 1 - Online supplement