Scientists in Denmark have just published the results of a long-term and large-scale study that examined the cellular health of 20,000 individuals for almost 19 years.
According to the University of Copenhagen, researchers have found cellular aging increases the risk of heart attack and early death.
The University reports the ongoing study observed the DNA of approximately 20,000 Danish people and analyzed their "specific telomere length," which is described as a measurement of cellular aging.
"The risk of heart attack or early death is present whether your telomeres are shortened due to lifestyle or due to high age," says Clinical Professor of Genetic Epidemiology Borge Nordestgaard from the Faculty of Health and Medical Sciences at the University of Copenhagen. Nordestgaard also serves as chief physician at Copenhagen University Hospital where large scale studies are conducted.
Experts explain telomeres as sequences of DNA , or "chains of chemical code," in the human body. Over time telomeres shorten as age occurs and the University of Utah explains "Cells normally can divide only about 50 to 70 times, with telomeres getting progressively shorter until the cells become senescent, die or sustain genetic damage."
Experts say lifestyle choices contribute to the shortening of telomeres, and University of Copenhagen researchers have long speculated it is this shortening that increases risk of heart attack. Smoking and obesity are said to be directly linked to telomeres being shortened, and thus lifestyle choices contribute to one's premature shortening of telomeres.
The recent study provides researchers with a direct link. Scientists have concluded that in instances where telomere length is short, risks for heart attack increased 50 percent, and premature death was increased by 25 percent. The study revealed one in four Danes have shortened telomeres.
"That smoking and obesity increases the risk of heart disease has been known for a while. We have now shown, as has been speculated, that the increased risk is directly related to the shortening of the protective telomeres - so you can say that smoking and obesity ages the body on a cellular level, just as surely as the passing of time," says Borge Nordestgaard.
The Copenhagen research also highlighted physicians could, in the future, conduct blood tests to examine their patients' cellular health, and this could help give indicators of telomere length and determine which patients are showing the increased risk.
In related, news, The Times of India reported today a new test will soon be available to determine telomere length.
Dr Jerry Shay, professor of cell biology at the University of Texas Southwestern Medical Center, a lead in developing the blood test told TOI,"Telomeres are like the plastic ends of a shoelace. As the plastic ends shred, the shoelace becomes frayed and damaged. Similarly the shortening of our telomeres can leave our cells vulnerable to damage."
Dr Shay is associated with Life Length, a telomere testing company based in Spain. TOI reported the test will cost approximately $500.
While the conclusions found by the University of Copenhagen provides additional insight, researchers note the need for more studies.
"Future studies will have to reveal the actual molecular mechanism by which the short telomere length causes heart attacks," says Borge Nordestgaard, and asks, "Does one cause the other or is the telomere length and the coronary event both indicative of a third -- yet unknown -- mechanism?"
The Danish study, titled,"Short Telomere Length, Myocardial Infarction, Ischemic Heart Disease, and Early Death," appears in the journal Arteriosclerosis, Thrombosis and Vascular Biology, which is published by the American Heart Association.