'Crown' Baldness Associated with Higher Risk of Heart Disease, Analysis Finds

Article excerpt

Male pattern baldness is associated with an increased risk of heart disease, but only if the baldness is on the crown of the head, a new meta-analysis of previous studies reports.

Among men with receding hairlines, no significant increase in risk was found.

Male pattern baldness is an inherited condition that affects about 30 to 40 percent of adult men -- a proportion that jumps to 80 percent by age 80, according to background information presented in the meta-analysis.

Previous studies have associated baldness with an increased risk of heart disease, but the strength of the risk varied widely. The Japanese authors of this new meta-analysis, which was published Wednesday in the online journal BMJ Open, decided to take a closer look at all the earlier research to see if they could clarify the relationship between male hair loss and heart disease.

What they found was interesting, but not definitive.

Focusing on six studies

The researchers searched Medline and the Cochrane Library databases for studies published on the topic between 1950 and 2012. They found 850 possibilities, but only six studies, involving about 37,000 men living in the United States and Europe, met their strict criteria and were included in the meta-analysis. These studies had been published between 1993 and 2008.

Three of the studies were cohort studies: They tracked men for up to 11 years. An analysis of those studies revealed that men with severe baldness on the top (vertex) of their head had a 32 percent increased risk of developing heart disease compared to men who had retained their hair. Among younger men (those who had not yet reached their 61st birthday), the risk was slightly greater: 44 percent. The percentages were reached after adjusting for other heart-disease risk factors, such as smoking, high blood pressure and obesity.

The analysis also found that the more severe the baldness, the greater the risk.

The other three studies were case-control studies, which are generally considered less rigorous than cohort ones. They compared the incidence of heart disease among bald men and non-bald men. An analysis of those studies revealed that bald or balding men were 70 percent more likely to have heart disease. In younger age groups, the risk jumped to 84 percent.

A possible marker

The reasons for the association between baldness and heart disease are unclear, the meta-analysis authors point out. It may be, however, that top-of-the-head baldness is a marker for insulin resistance or chronic inflammation or some other factor that promotes heart disease. …