In a recent study, Dr. Stella Daskalopoulou at McGill University Health Centre found that smoking one cigarette increases the stiffness of the arteries in 18 to 30 year olds by a whopping 25 per cent. Proof that lighting even a single ciggie could be putting young adults in harm's way.
Arteries that are stiff or rigid increase resistance in the blood vessels, making the heart work harder-the stiffer the artery, the greater the risk for heart disease or stroke.
"Young adults aged 20-24 years have the highest smoking rate of all age groups in Canada. Our results are significant because they suggest that smoking just a few cigarettes a day impacts the health of the arteries. This was revealed very clearly when these young people were placed under physical stress, such as exercise," said Daskalopoulou.
In the study, the researchers compared the arterial stiffness of young smokers (five to six cigarettes a day) to non-smokers. The median age was 21 years.
Arterial measurements were taken in the radial artery (in the wrist), the carotid artery (in the neck), and in the femoral artery (in the groin), at rest and after exercise.
Arterial stiffness in both smokers and non-smokers was measured using a new but well-established method called applanation tonometry.
Dr. Daskalopoulou introduced the 'arterial stress test', which measures the arteries' response to the stress of exercise and is similar to a cardiac stress test, which measures the heart's response to the stress of exercise.
"In effect we were measuring the elasticity of arteries under challenge from tobacco," explained Daskalopoulou.
After the first meeting, smokers returned and smoked one cigarette each and then repeated the stress test.
Daskalopoulou found that after exercise the arterial stiffness levels in non-smokers dropped by 3.6 per cent.
However, in smokers the results were reverse- after exercise their arterial stiffness increased by 2.2 per cent.
After nicotine gum, it increased by 12.6 per cent and after one cigarette it increased by 24.5 per cent.nterestingly, there was no difference in the arterial stiffness measurements between smokers and non-smokers at rest.
"In effect, this means that even light smoking in otherwise young healthy people can damage the arteries, compromising the ability of their bodies to cope with physical stress, such as climbing a set of stairs or running to catch a bus. It seems that this compromise to respond to physical stress occurs first, before the damage of the arteries becomes evident at rest," said Daskalopoulou.
The study was presented at the Canadian Cardiovascular Congress 2009, co-hosted by the Heart and Stroke Foundation and the Canadian Cardiovascular Society.