Many smokers consider themselves non-smokers. This is because they do not smoke every day. These social, intermittent or just occasional smokers are very common – they represent an additional half of the number of people that consider themselves regular smokers but because they don’ smoke every day they don’t consider themselves “smokers”. Whilst some realise that intermittent smoking is of concern about 30% of intermittent smokers believe that the amount they smoke is not enough to cause health problems.
However, whilst the risk of lung cancer is directly related to the number of cigarettes smoked, this is not true for cardiovascular health. Even a small number of cigarettes increases your cardiac risk and as few as the first 4-5 cigarettes per day are enough to provide the majority of the total overall risk.
The recent regulations at preventing smoking in public places have shown a reduction in acute myocardial infarction not only in smokers but also in non-smokers.
The reduction has been variously reported as from 20 to 40%.
This strongly suggests that the trivial inhalation of smoke may be critical in whether an unstable plaque forms a thrombosis or whether it does not. This is keeping with experimental data looking at the acute effects of smoke on the constriction of blood vessels and a pro-inflammatory effect making a thrombosis more likely.
Because of the considerable success of reducing acute admissions from heart attacks in the general population by legal restrictions on public smoking. There may now be increased focus on explaining the risks to intermittent smokers, who are often female and young, and this has already started in Norway – see the accompanying public health message…
Some women may be at particular risk of intermittent smoking
This may be of particular importance to identify those female patients who are over 35 and on the oral contraceptive pill and those with a history of pre-eclampsia or low birth size babies – these women have recently been identified as having future high risk of cardiovascular events – intermittent smoking could be the final additional stress that provokes a heart attack.
Smoking even a few cigarettes increases your risk of cardiovascular events well beyond the perceived risk.