It has long been known that smoking and lung cancer are causally linked. After having discovered this association though, much has been made of the heightened incidence of other forms of cancer caused by of smoking. I am going to highlight the data that reiterates the claims and suggest that the evidence is not so strong for other forms of cancer being causally linked with smoking. The evidence is analysed from the mortality statistics for the UK in 2002.
I will work through the statistics because 26% of the population are smokers and so one might reasonably assume that any incidence of cancer where less than 26% of sufferers are smokers may have other more prevalent caused.
Firstly, we will deal with the cancer deaths so lets get underway with the 33,600 deaths from lung cancer. 84% of these deaths were in smokers. This means that the average 26% of the smoking population yielded more than three times the proportion of deaths – a clear link.
Oesophageal cancer deaths numbered just under 5,000 and the deceased were found to be 66% smokers, 71% and 65% men to women respectively; again another clear link that smoking and oesophageal cancer are linked.
Next, bladder cancer takes over 1,800 lives per year of which 37% are found to be smokers. However, only 19% of female cases were smokers compared with 47% of male cases. It is fair to assume that there are other factors more prevalent in female bladder cancer other than smoking but the link is clear in men.
Stomach cancer took 1,650 lives in 2002 but is found in 35% of men compared with only 11% of female smokers. It is reasonable therefore to draw the same conclusion about the causes as for bladder cancer between men and women.
Pancreatic cancer is another cancer that is less prevalent in smokers than the general population. Indeed 20% of men and 26% of women dying from the disease in 2002 were smokers, suggesting parity with women and a disparity with men. It may be reasonable therefore to assume that there are other contributory factors in male pancreatic cancers.
Death from cancer of the upper respiratory tract was found at a rate of 66% in smokers, nearly three times the percentage of smokers. Note though that women sufferers represented half of their cohort compared with three quarters of men, suggesting upper respiratory cancer is more likely in men than in women smokers.
Kidney cancer is another cancer where smokers are seen less frequently than non-smokers in the statistics.
The next disease we shall look at is the non-cancerous, chronic obstructive pulmonary disease or COPD. The disease manifests itself mainly in two forms, being emphysema and chronic bronchitis.
Emphysema is the destruction of the lung leading to loss of surface area, alveoli (air sacks in the lungs) and the loss of elasticity. Chronic bronchitis manifests itself through swollen bronchi and over production of mucus within the lung. It is characterised by daily coughing bringing up sputum. Both emphysema and bronchitis lead to slow, debilitating and frustrating deaths for their victims.
Deaths from COPD in 2002 in the UK numbered 28,500 of which 84% were smokers demonstrating a clear link between the inhalation of tobacco smoke and the disease.
Some sources suggest that pneumonia is more likely to kill in smokers but only 17% of the 36,000 fatal pneumonia cases were found in smokers suggesting this is not the case.
Finally, heart disease is the biggest single killer in the UK with over a quarter of a million deaths a year as a result of its various forms.
Of all the major forms of heart disease, ischaemic heart disease, cerebrovascular disease, aortic aneurysm, myocardial degeneration and atherosclerosis, the percentage of smokers suffering from aortic aneuryism was just under 60%. All other forms of heart disease showed near 26% or below. This suggests that smoking may not be the main contributory factor but it almost certainly will have had an impact.
All in all, there were 114,500 premature deaths from cigarette smoking, mostly from cancer, but also from heart disease and pulmonary (lung) disease. The best way to improve ones chances of not suffering from a shortened life and succumbing to one of the diseases mentioned in this article is by quitting smoking once and for all. Benefits have been clearly documented and the sooner smokers quit, the bigger the benefits of quitting become on their life expectancy. Indeed, smokers who quit before they reach thirty, statistically negate virtually all the ill health effect of smoking and can generally expect to live as long as a non-smoking contemporary.