Quitting smokeless tobacco products following a heart attack can help increase life expectancy similar to those who stop smoking, according to an Uppsala University study.

"We didn't expect to see such a strong association among those people who stopped using (smokeless tobacco)," said Gabriel Arefalk, M.D., lead researcher and cardiologist at Uppsala University Hospital in Uppsala, Sweden, in a press release. "After a heart attack, no doubt smoking cessation reduces the risk of death approximately one third and is really a cornerstone of cardiac rehabilitation worldwide. For smokeless tobacco, we did not know."

This is the first study to analyse the impact of smokeless tobacco on mortality in heart attack survivors.

For the study, the researchers examined the effect of giving up of snus, a moist Swedish smokeless powder tobacco kept under the upper lip. It is a modified version of snuff, but doesn't need to be spit out.

The researchers studied the data of heart attack survivors younger than 75 in Sweden in 2005-09. Among the survivors, 2,474 of them were snus users. Around 675 of the 2, 474 quit snus. During two years observation of 2,474 patients - 14 non-snus users died, while 69 of snus users lost their lives.

Through a mathematical analysis, the researchers found that the death rate was 9.7 per 1,000 person-years at risk for snus quitters and 18.7 for snus users. They also said that patients who stopped using snus were associated with 50 percent of the mortality risk that is similar to those identified with smoking cessation.

The finding is published in the American Heart Association journal Circulation.