The grayer his hair, the higher his heart risk?

Beyond signaling the march of time, gray hair may also point to a higher risk of heart disease for men, new research suggests.

But don’t panic if you sport silvery locks -- the study only showed an association, not a cause-and-effect link, between hair color and heart risks.

The finding stems from an analysis that looked at 545 adult men for signs of heart trouble, and then cross-referenced the results with hair color.

“In our population, a high hair-whitening score was associated with an increased risk of atherosclerotic coronary artery disease,” said study author Irini Samuel. She is a cardiologist at Cairo University in Egypt.

Atherosclerosis refers to the build-up of plaque in the arteries.

Samuel said the finding held up regardless of a man’s age or whether or not he was already known to face a high risk for developing heart disease.

The frequency with which women tend to color their hair made it impossible to include them in the analysis, Samuel noted. So, her team focused exclusively on men, all of whom underwent scans that looked for indications of heart disease such as plaque build-up.

The participants -- ranging in age from 42 to 64 -- were then divided into five groups based on the degree to which their hair had grayed. The groups ranged from “pure black hair” at one extreme to “pure white” at the other, with shades of gray in between.

The investigators found that 80 percent of the participants showed signs of heart disease. And those who did registered “significantly higher” in terms of hair-whitening scores.

The researchers noted that simply getting older boosts the likelihood that a man’s hair will turn gray.

However, at the same time, graying hair may also go hand-in-hand with unhealthy “biological aging,” since both unfold along similar lines, the research team suggested.

Those lines include several forms of cellular-level degradation, Samuel explained, including an increasing risk for system-wide inflammation, hormonal changes and an impaired ability for DNA to repair itself and for cells to divide and grow.

More research will be needed to better understand the genetic and environmental underpinnings of the link, as well as to explore whether or not a similar association exists among women, Samuel said.

Meanwhile, she suggested that any patient who believes that he or she may already face a high risk for heart disease “should have regular check-ups to avoid early cardiac events by initiating preventive therapy.”

The study findings were presented this week at the European Society of Cardiology annual meeting, in Malaga, Spain. Research presented at meetings should be considered preliminary until it is published in a peer-reviewed journal.

Dr. Gregg Fonarow is a professor of cardiology with the University of California, Los Angeles. He said that a possible link between heart disease and graying hair was “first reported in the medical literature in the 1980s,” with some studies indicating a link among both men and women.

“Since then, some additional studies have suggested that premature graying of hair is a risk factor for coronary artery disease, independent of age, whereas other studies have not found this association,” Fonarow added.

The upshot, he said, is that while graying hair may turn out to be an indicator of risk, most of the focus to date has stayed centered around clearly “modifiable” risk factors, meaning behaviors that patients can change. Those include shedding weight, quitting smoking and taking steps to reduce high blood pressure and cholesterol.