Cigarette Smoke And Disease: Epidemiological Evidence Experimental Evidence Early Death

Cigarette Smoke and Disease

Epidemiological Evidence Experimental Evidence Early Death

Proving the links between smoking and lung disease 

Serious widespread smoking did not start until the second half of the 20th century.  In the 1950’s there was a lung cancer epidemic.  There are now over 35,000 deaths per year from lung cancer.  In general, 50% of smokers die from a smoking related disease.

Chronic Obstructive Pulmonary Disease 

This is where chronic bronchitis and emphysema occur at the same time.  The disease is responsible for 30,000+ deaths a year in the UK.  It is very rare in non-smokers.  98% of people with emphysema are smokers!!!

Some more statistics 

Smokers are 18 time more likely to develop lung cancer than non-smokers.  25% of smokers die of lung cancer.  It takes ten years for lungs to recover after a long period of smoking.  One third of all cancer deaths are a direct result of smoking.

Figure 14.4 The Smoking epdemic consumption of cigarettes and deaths from lung cancer in the UK between 1911-1991

Men Women Increase in smokers 1911-1941 Sharp increase in smokers 1941-1975 Deaths for cancer correlate Deaths for cancer correlate 20 year lag 20 year lag

Overall Smoking causes lung cancer in both men and women Prediction for 2011?

Experimental Evidence 

Dogs were used!  Mice were used!  Vital research that should save lots of human lives!

The Dog Experiments 

One group of dogs were made to smoke filtered cigarettes.  They did not get lung cancer but did produce cancerous cells in the lining of their airways and mouths.  One group of dogs were made to smoke filter-less cigarettes.  They did get lung cancer.

The Smoking Machine Experiments 

Smoking machines extracted the chemicals in smoke.  Carcinogens and co-carcinogens were found in the tar.  When the tar was rubbed on the back of a mouse. The skin formed cancerous cells!!!

The Trends of Smoking

Developed world?

Developing world?

Atherosclerosis

A cardiovascular disease

Atherosclerosis 

This is where too much cholesterol has been taken and is stored in the arteries causing them to narrow.  If an artery to the heart is blocked a heart attack could occur.  If an artery to the brain is blocked then a stroke could occur.

…more! 

Cholesterol travels in packages called lipoproteins.  There are low density lipoproteins that deliver cholesterol around the body.  There are high density lipoproteins that remove cholesterol from the blood stream.  Cholesterol is essential but in the right amounts!!