Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: FRIDAY, August 18, 1995 TAG: 9508180100
SECTION: NATL/INTL PAGE: A8 EDITION: METRO
SOURCE: THE NEW YORK TIMES
DATELINE: LENGTH: Medium
The risk of heart attacks for young adult smokers is about double what had previously been believed, said the researchers from Oxford University, who conducted the study in Britain.
The study involved 46,000 people and extended findings from many earlier studies that showed that smoking increases the risk of heart attacks in older people.
``When cigarette smokers have a heart attack in their 30s and 40s, there is an 80 percent chance that tobacco caused it,'' said Dr. Rory Collins, a co-author of the report, in Saturday's issue of The British Medical Journal.
Dr. Richard Peto, another co-author, said, ``These results mean that every year smoking causes 40,000 heart attacks among Americans who are still only in their 30s or 40s.''
Most young adult smokers who had heart attacks started as teen-agers, Peto said, and the study found a tendency for a higher risk among those who started smoking earliest. About one-fifth of the heart attacks in young adults are fatal.
The younger a person is when he or she suffers a heart attack, the more likely it is that smoking caused it.
The Oxford study also found that smokers in their 50s tripled their risk of heart attack and those in their 60s and 70s doubled their risk.
Expressing the statistics in another way, the British study found that among cigarette smokers, the proportion of heart attacks that were caused by tobacco is four-fifths for those in their 30s and 40s, two-thirds in those in their 50s, and one half for those in their 60s and 70s.
One reason the increased risk is greatest among younger adults is not because tobacco is more dangerous in younger people but because heart attacks are much less common among younger people than among older people.
The researchers also assessed the risk of heart attack based on whether the participant smoked medium- or low-tar cigarettes. The risks of heart attacks were slightly greater with medium-tar rather than low-tar cigarettes, but the difference was not definite.
Differences in risk between smokers and nonsmokers are far greater than any differences in risk between one type of cigarette and another, the researchers said.
Far more heart attacks could be prevented by not smoking than by reducing cigarette tar yields, the researchers said. ``This huge study shows that there's no such thing as a safe cigarette,'' Collins said. ``They are all good at killing you.''
Dr. Clark Heath, an official of the American Cancer Society in Atlanta, saidthat the data in the new study were ``very good'' and ``quite similar to United States data,'' adding: ``The study says that all the tinkering with cigarettes to make a safe cigarette is unsuccessful at least as measured by heart attacks as an outcome. Even low-tar cigarettes produced a big risk.''
Peto said that overall, half of all persistent smokers die from tobacco-related illnesses, and heart attacks are the main way that tobacco kills young adults.
The Oxford team studied 14,000 heart attacks patients and 32,000 of their relatives who did not have a heart attack and who served as scientific controls for purposes of comparison.
As part of a questionnaire, all were asked which of 137 cigarette brands they smoked and how many each day. Most respondents said they had smoked the same brand for the past 10 years.
Heart attack survivors have a reduced chance of a recurrence if they stop smoking. ``But stopping smoking before you have had one is even better,'' Peto said.
by CNB