It is a fact that smoking is harmful to one’s health and associated with deadly diseases such as cancer and cardiovascular disease. It is also a fact that smokers die earlier than non-smokers. But a new study sheds light on the direct causal relationship between smoking and mortality by investigating genes has never been published before.
A large-scale study by University of Copenhagen and Copenhagen University Hospital shows a direct correlation between smoking and mortality. Researchers looked at blood samples from more than 55,000 Danes and found that a special gene variant increases the risk of heavy smoking. Of this figure, 32,823 were smokers who were followed by 10 years.
“Smoking is associated with premature death, and heavy smokers have a 75 percent higher risk of dying than never-smokers of the same age. This may not come as a surprise, but it is actually the first time that this type of study – which presents a direct causal relationship between smoking and mortality – has been carried out,” says Professor and chief physician Børge Nordestgaard from the University of Copenhagen and Copenhagen University Hospital.
Interestingly, the study identified a special gene variant that impacts heavy smoking. According to the researchers, the smoking gene has no influence on whether you start or quit smoking. However, as one smokes and continues to smoke, the gene makes the person smoke more. Findings revealed that People who have inherited the gene variant from both their parents smoke 20 percent more than those without the special gene variant.
“There is a lot to suggest that you can be genetically predisposed to heavy smoking. Smokers carrying a special genetic mutation have a higher tobacco consumption – and they are more affected by smoking, e.g. by having higher blood nicotine levels. They quite simply smoke more convincingly – which is, of course, very harmful for their health – and they have a 14 percent higher risk of dying before other smokers,” says Børge Nordestgaard.