Paris: Smokers under 50 are eight times more likely than non-smokers of the same age to have a major heart attack, scientists said Wednesday.
The gap in risk between those who do and don`t consume tobacco diminishes with age, dropping to a five-fold difference among 50-to-65 year-olds, and a three-fold gap among over-65s, the team said.
The findings are surprising because younger men and women typically do not have as many of the health problems -- diabetes, high blood pressure or cholesterol -- associated with an increased chance of heart failure.
"Smoking is perhaps the most powerful of all risk factors, exerting its effect much sooner than any other," concluded the study, published in the journal Heart.
All smokers face a markedly higher danger of heart attacks than non-smokers, but it had not been clear how the risk compared between age brackets.
To find out, a team of researchers led by Ever Grech of The South Yorkshire Cardiothoracic Centre at Northern General Hospital in Sheffield, England, examined data from 1,727 adults who underwent treatment for a common type of heart attack -- known by the acronym STEMI -- between 2009 and 2012.
Such attacks result in a large portion of the heart muscle dying.
Nearly half the patients were current smokers. The rest were almost evenly divided between ex-smokers and people who had never picked up the tobacco habit.
On average, current smokers were at least a decade younger than ex- or never-smokers when the heart attack hit, the study found.
They were also twice as likely as non-smokers to previously have suffered from coronary artery disease.
Across the population of South Yorkshire, 27 percent of adults under the age of 50 consumed tobacco, said the study. But nearly 75 percent of STEMI heart attack patients under 50 were smokers.
Overall, smokers were more than three times as likely to have a STEMI than ex- and non-smokers combined, the data showed.
The results should be a wake-up call to young smokers, the researchers warned.
"Further efforts to reduce smoking in the youngest are needed," the study said.
The researchers added "it is difficult to explain the much higher risk" of acute heart attack among younger patients.
Writing in the same journal, cardiologist Yaron Arbel of the Tel Aviv Medical Center in Israel, said the goal should be on helping younger smokers quit.
And if that proves impossible, "even reducing the number of cigarettes smoked daily might make a difference," he said.