Now that this year’s Stoptober campaign has come to an end, Rod Tucker reflects on advice pharmacists should give to patients
Everyone is aware that smoking is harmful to health – according to the NHS, it is responsible for around 78,000 deaths each year. Smoking increases the risk of heart disease, stroke as well as peripheral arterial disease but is also responsible for a sizeable number of cancer-related deaths. For instance, one US analysis estimated that in over 345,000 cancer-related deaths, 48.5% were attributable to smoking.
Smoking adversely affects lung function and although lung function normally declines with age, smoking accelerates this age-related decline and is the most common cause of chronic obstructive pulmonary disease. However, perhaps the greatest risk from smoking is lung cancer. In fact, according to Cancer research UK, smoking accounts for 72% of lung cancer cases in the UK.
Although levels of smoking have declined in recent years, there are still approximately 7.2 million people in the UK aged 18 years and over who are smokers. Reduced levels of smoking, ie those who consider themselves to be recreational or social smokers consider the practice to be less harmful. But is there evidence to support this viewpoint?
A recent study set out to try and answer this question by examining changes in lung function. The authors focused on studies using spirometry which evaluates lung function in terms of the forced expiratory volume in one second (FEV1) as lower values are linked to a more severe decline in lung function. Data was available for over 25,000 people who were followed up for an average of seven years.
The researchers compared lung function among non-smokers, former smokers and current smokers. They analysed separately people who reported smoking either five or less cigarettes per day and heavy smokers (defined as over 30 cigarettes per day). For comparative purposes, they calculated the average decline in lung function for people aged 57. The results showed that for a typical 57-year-old non-smoker, the average decline in lung function was 31 ml/year. It was slightly higher at 35ml/year in former smokers but nearly 40ml/year among current smokers.
Interestingly, even among former smokers, the decline in lung function was still slightly faster (1.82 ml/year) than in those who had never smoked. A further key finding was that in people who smoked five or less cigarettes per day, the decline in lung function was 7.65 ml/year more than non-smokers, but 11.24 ml/year among those smoking 30 or more cigarettes a day.
These results are a concern for anyone who has previously smoked, continues to smoke heavily or even perceives themselves to be a light or social smoker. In each case, the damage to the lungs would appear to be irreversible and still present (albeit at a lower level) years later.
The only ‘good’ news from the study was that among smokers without any form of lung disease, the decline in lung function became the same as non-smokers once they had quit. The study did have some limitations, however. Smoking status and the amount smoked was self-reported and therefore subject to bias; in reality, people may have smoked more or less than they reported.
Although the study showed that the decline in lung function was less for light smokers, other work has shown that even smoking one cigarette per day carries a risk of developing heart disease and stroke and is around half of that for people smoking 20 cigarettes per day.
Implications for practice
As an important source of advice to patients who wish to stop smoking, pharmacists should emphasize that while a reduction in the number of cigarettes smoked causes less damage, there is really no ‘safe’ level of smoking.
Patients should see cutting down as a step towards abstinence rather than a goal in itself. Effective therapy to help those wishing to stop smoking is available in the form of nicotine replacement therapy which increases the chance of quitting by 50 to 60%.