As if losing your hair wasn't bad enough, a new study has linked male pattern baldness to an increased risk of coronary heart disease. Could the male population be made up of modern day Samsons?
Bald picture from Shutterstock
Researchers from the University of Tokyo studied the link between pattern baldness and coronary heart disease in approximately 40,000 men using data from the Medline and the Cochrane Library. They found that men who had lost most of their hair were up to 70 per cent more likely to develop some form of heart disease than their non-balding counterparts:
The present meta-analysis demonstrated that vertex baldness was significantly associated with an increased risk of CHD among participants of all ages and also among younger men.
The likelihood of developing heart disease was also found to increase along with the severity of baldness. Curiously, the link between baldness and heart disease was only present in men with thinning crowns. Men with receding hairlines were not affected.
The researchers suggest a number of possible reasons for the link between baldness and heart disease, including insulin resistance, a precursor to diabetes, a state of chronic inflammation and increased sensitivity to testosterone.
The report concludes that cardiovascular risk factors need to be reviewed carefully in men with vertex baldness, especially younger men, and they probably should be encouraged to improve their cardiovascular risk profile. However, they acknowledge that the usefulness of CHD screening in asymptomatic patients is yet to be proven:
Patients should be evaluated for eligibility before screening to avoid possible over-medicalisation since male pattern baldness affects 30–40% of adult men.
Scientists respond to findings
Several UK scientists have released statements questioning the validity of the study's findings, particularly in the area of risk calculations.
“These figures on increased risk aren’t actually known very precisely," said Professor Kevin McConway, Professor of Applied Statistics, Faculty of Mathematics at The Open University. "From the paper we can see that the increase [in risk] might plausibly be an 11% increase, or any 86% increase, or anywhere in between. There just isn’t enough information to be more precise.
“The researchers also suggest that bald younger men should be encouraged to improve their heart risk profile, presumably by healthier eating, giving up smoking and so on, but that probably applies to all of us…I won’t be advising my bald friends to do anything different.”
Professor Patrick Wolfe, Royal Society Research Fellow and Professor of Statistics at University College London adds: "It is important to remember that the study reports an increase in relative risk, after factors such as body mass index and smoking have been taken into account. So, if we consider the case of two male, non-smoking marathon runners in top physical condition, one of whom is bald and the other not, then their absolute risks for heart disease are likely to be quite small."
Professor David Spiegelhalter, Winton Professor of the Public Understanding of Risk at the University of Cambridge, was similarly skeptical: “This study estimates that keeping hair on your crown is associated with a similar reduced risk of heart disease as taking a statin. But sensibly no causal link is made: it's a nice example of where a common factor may contribute to both baldness and heart disease."
All of the scientists that released statements said that while the findings are interesting, additional research is definitely needed. In other words, if you do suffer from baldness, we wouldn't start pricing pacemakers just yet.