New research suggests that the amount of gray hair may be an indication of heart disease risk in men.
In atherosclerosis, plaque - which is made of cholesterol, fat, calcium, and other substances - starts building up inside the blood vessels. With time, this plaque becomes calcified, limiting the elasticity of the arteries and the supply of blood to the heart and other vital organs in the body.
One of the main cardiovascular events connected with atherosclerosis is coronary artery disease, also called coronary heart disease. This disease occurs as a consequence of plaque building up inside the coronary arteries - the two main blood-supplying arteries that start from the heart's aorta.
It is well-known that aging is a risk factor for heart disease. Furthermore, atherosclerosis and graying hair have similar causes: the damaged DNA that comes with aging, increased oxidative stress, and the aging of cells.
A new observational study - presented at the EuroPrevent 2017 conference of the European Society of Cardiology - suggests that the amount of gray hair in adult men is correlated with an increased risk of heart disease.
Studying the link between gray hair and heart disease in adult men
The researchers examined 545 adult men who were suspected of having coronary artery disease and divided them into several subgroups based on whether they had the disease, and according to how much gray hair they had. The men had also been examined using a multi-slice computed tomography coronary angiography because they were suspected of having the disease.
The team graded the level of gray hair using the following scale: 1 for pure black hair, 2 for more black hair than white, 3 for an equal amount of black and white hair, 4 for more white hair than black hair, and 5 for pure white hair. Each participant was assessed by two independent observers and received a hair whitening score.
Additionally, the researchers collected clinical data on the participants' risk factors for cardiovascular disease (CVD), such as hypertension, smoking, diabetes, dyslipidemia - that is, high blood cholesterol levels - and a family history of CVD.
The team used multivariate regression analyses and found that age, hair whitening grade, high blood pressure, and dyslipidemia all predicted atherosclerotic coronary artery disease independently.
Graying hair 'could be used as a predictor for coronary artery disease'
The study found that patients with coronary heart disease had a greater hair whitening score and increased levels of coronary artery calcification compared with their healthy counterparts.
More specifically, a high hair whitening grade - typically 3 or higher - correlated with an increased risk of coronary artery disease. This correlation was independent of age or CVD risk factors.
Study co-author Dr. Irini Samuel, a cardiologist at Cairo University in Egypt, comments on the significance of the findings:
"Atherosclerosis and hair graying occur through similar biological pathways and the incidence of both increases with age. Our findings suggest that, irrespective of chronological age, hair graying indicates biological age and could be a warning sign of increased cardiovascular risk.
More research is needed on cutaneous signs of risk that would enable us to intervene earlier in the cardiovascular disease process."
Dr. Samuel also recommends that high-risk patients who may not have any symptoms of coronary artery disease have regular checkups in order to avoid heart disease and start taking preventive measures. She also notes that more research is needed to confirm their findings.
"Further research is needed, in coordination with dermatologists, to learn more about the causative genetic and possible avoidable environmental factors that determine hair whitening," she says. "A larger study including men and women is required to confirm the association between hair graying and cardiovascular disease in patients without other known cardiovascular risk factors."
"If our findings are confirmed," Dr. Samuel concludes, "standardization of the scoring system for evaluation of hair graying could be used as a predictor for coronary artery disease."