MONDAY, June 23, 2014 (HealthDay News) -- A new study suggests that heart attack patients who stop using snus -- a specific type of moist chewing tobacco that is popular in Sweden -- could greatly reduce their risk of dying within a couple years.
The findings don't directly prove that stopping the use of this type of smokeless tobacco actually affects cardiac health, and ethical constraints may prevent researchers from ever understanding the full value of quitting. There are other caveats, and it's not clear that quitting the main kinds of smokeless tobacco used in the United States would have the same potential effect.
Still, the study "indicates that quitting snus use after a heart attack might be as equally beneficial as quitting smoking after a heart attack," said study author Dr. Gabriel Arefalk, a cardiologist at Uppsala University Hospital in Uppsala, Sweden.
The health risks of smokeless tobacco have been in the news over the past week because of the death of baseball legend Tony Gwynn at the age of 54. Gwynn blamed his initial salivary gland cancer on a long history of chewing tobacco, although doctors say there's no definitive link between that kind of tobacco and that type of cancer.
It's clear, however, that smokeless tobacco poses major risks to health and causes other kinds of cancer.
Smokeless tobacco comes in a variety of forms, including traditional chewing tobacco (which may come in loose leaves or "plugs") and snuff (finely cut or powdered tobacco), according to the U.S. National Cancer Institute. The new study examines snus (rhymes with "moose"), a kind of moist snuff that doesn't need to be spit out because users typically swallow the tobacco juices.
"Snus is very different from American chewing tobacco such as Red Man or American moist snuff such as Skoal or Copenhagen," explained Dr. John Spangler, a professor of family and community medicine and psychiatry and behavioral medicine at Wake Forest School of Medicine. "Snus is pasteurized by steam, while American smokeless tobacco is cured in a heated environment over time. Curing generates more cancer-causing agents, so some tobacco experts argue that snus is safer and want tobacco companies to be able to market snus as safer."
Snus is especially popular in Sweden, where 20 percent of adult men and 3 percent of adult women use it.
The researchers tracked almost 2,500 snus users, mostly men, who were younger than 75 and had heart attacks between 2005 and 2009. Only about one-fourth -- 675 -- quit using snus, while the rest continued.
Fourteen of those who quit and 69 of those who continued to use snus died over an average of about two years. Those who quit were about half as likely to die as those who continued using the smokeless tobacco, after researchers adjusted their statistics so they wouldn't be thrown off by high or low numbers of people of certain ages or genders.
What's going on? Researchers aren't sure. Those who quit using smokeless tobacco could simply be healthier overall or they might have started taking better care of themselves, although the researchers tried to account for this possibility. Those who kept using snus were also more likely to have diabetes.
The researchers speculate that something about snus -- possibly the nicotine -- hurts the heart, perhaps by making it more vulnerable to damage from irregular heartbeats.
The findings may reveal little if anything about the smokeless tobacco that's used in the United States, even the snus that's sold here. "There are snus-type products available in the U.S. market currently, but the American products are manufactured and sold differently than Swedish snus, and there are no studies on the health effects of products sold in the U.S. labeled 'snus,'" said Dr. Pamela Ling, an associate professor with the University of California, San Francisco's Center for Tobacco Control Research and Education.
However, "smokeless tobacco use of all types is associated with increased risk of cardiovascular disease, so the results of this study on snus probably also apply to other forms of smokeless tobacco," she said. "Patients with heart attacks should be encouraged to quit all forms of tobacco, both cigarettes and smokeless tobacco."
The study appears online June 23 and in the July 22 print issue of the journal Circulation.
Visit the U.S. National Cancer Institute for more on smokeless tobacco.