All forms of tobacco exposure affect cardiovascular health

All forms of tobacco exposure wether it is consumed through chewing, smoking, puffing on "bubble" pipes or even second-hand smoke can lead to an increased risk of heart attack, a Canadian Interheart study involved 27,000 people in 52 countries around the world has revealed.

The study led by two Canadian researchers, Dr. Koon Teo and Dr. Salim Yusuf of McMaster University in Hamilton, Ontario, revealed that heart attack risk increased three-fold in smokers compared to completely non-smokers.

Dr. Teo says because of the magnitude of the study, he and colleagues from around the world were able to confirm an array of postulations and suspicions about the effect tobacco has on cardiovascular health.

He said in an interview on Thursday that in this study, "we included practically all the regions of the world, so we can say that the results apply to all ... different types of people."

The research, published in the Lancet, shows the risk of acute myocardial infarction (AMI) or a heart attack was increased by exposure to tobacco in all kinds, to prove this, it provided concrete evidence that secondhand smoke was harmful to the heart. A person with the highest levels of passive smoking exposure, 22 hours or more per week, developed their risk of a heart attack by nearly 45%. Furthermore, chewing tobacco doubled the risks of having a heart attack, as did smoking eight to 10 cigarettes a day.

The study also noted an increased risk in those who smoke ‘beedies’ (a small amount of tobacco wrapped in a dried temburini leaf smoked in South Asia) and ‘sheesha’ (a water pipe), as well as other kinds of smoked and non-smoked tobacco used worldwide.

In their study, researchers noted that heart attack risk decreased with time after people quitted smoking. "For people who smoke lighter, maybe up to 10 cigarettes a day, after five years the risk is almost gone," said Teo.

On the other hand, people who smoked 20 or more cigarettes a day still had a 22% increased risk 20 years after giving up.

Prof. Salim said: "Since the risks of heart attack associated with smoking dissipate substantially after smoking cessation, public health efforts to prevent people from starting the habit and promote quitting in current smokers, will have a large impact in the prevention of heart attacks worldwide."

In an attempt to boost the will power of the smokers who want to quit the smoking, Teo says, "The risk they are suffering actually diminishes very quickly so it's never too late to quit."

The study, which is labeled as “outstanding work” by scholars was, funded by the Canadian Institute of Health Research, the Heart and Stroke Foundation of Ontario and the International Clinical Epidemiology Network. It also received endorsement from various global pharmaceutical companies and organizations.