UK control Lungs Cancer

Britain has the largest decrease in the world in premature deaths from lung cancer, and widespread smoking cessation is the chief reason, according to a major new study to be reported in this week's British Medical Journal by Sir Richard Doll, whose work 50 years ago first linked smoking to lung cancer in the UK. Speaking at a BMJ press conference today (2 August), Professor Doll, age 87, from Imperial Cancer Research Fund's Oxford unit, said: "Our 1950 study showed that smoking was a cause of most of the lung cancer in Britain at that time, and our new study shows that widespread cessation of smoking has halved the number of lung cancer deaths that would otherwise be occurring in Britain in the year 2000."
The 1950 study was the first to link lung cancer in Britain to smoking. It compared the smoking habits of 1,465 people with lung cancer and 1,465 without the disease. The new study compares the smoking habits of 982 people with lung cancer and 3185 without it. Because so many smokers have stopped, the new study can assess the effects of prolonged cessation. It finds that, among men who continue to smoke, 16% will die from lung cancer before age 75 (unless they die of something else first). But, for those who stop at age 50 this risk is only 6%, and for those who stop at age 30 it is less than 2%. See fig. 3
Nationwide effects on lung cancer deaths of big changes in smoking often show up first among men in early middle age. The UK had about the worst lung_cancer_death rates in the world in 1950, but has had the best decrease since then. The US is lagging 25 years behind, but since the 1970s US male lung cancer mortality in early middle age has halved. See fig. 2a, 2b, and other graphs and data of lung cancer deaths since 1950 (male & female, early middle age & later) for the UK, US and many other developed countries.
In addition, smoking kills many more people by other diseases than by lung cancer: overall, half of all cigarette smokers will eventually be killed by tobacco if they don't stop. But, even the smokers who stop in middle age avoid most of their later risk of being killed by tobacco, and those who stop before middle age avoid nearly all the risk. Said Professor Doll: "In 1950, 80% of the men and 40% of the women in Britain smoked, and tobacco deaths were increasing rapidly. Nowadays, among people over the age of 50 there are twice as many ex-cigarette smokers as cigarette smokers, and tobacco deaths are decreasing rapidly. But, smoking is still the biggest cause of premature death in Britain." There have been six million deaths from tobacco in Britain over the past 50 years, of which three million were deaths in middle age (35-69). Those killed by tobacco in middle age lost, on average, more than 20 years of life.
Professor Sir Richard Peto of the Imperial Cancer Research Fund's Oxford unit and co-author of the new report said "There are still 10 million smokers in Britain, and about five million will be killed by tobacco if they don't stop. In the United States there are 50 million smokers: about 25 million will be killed by tobacco if they don't stop. Tobacco deaths over the next 50 years will be affected much more by the number of adults who manage to stop than by the number of adolescents who start smoking."
Professor Peto cautioned that while premature deaths from tobacco are decreasing in Britain, and are beginning to decrease in some other developed countries, they are increasing rapidly in many other countries. Worldwide, there were about 100 million (0.1 billion) tobacco deaths in the 20th century, but if current smoking patterns continue there will be about 1,000 million (1 billion) in the 21st century. The increase is partly because of population growth, and partly because the increases over the past few decades in cigarette smoking by young adults imply increases over the next few decades in deaths from tobacco (if those young adults continue to smoke as they reach middle and old age). There are currently 1.1 billion smokers in the world.
Sir Richard Peto said: "On present smoking patterns there will be about 150 million tobacco deaths in the first 25 years of this century and 300 million in the second quarter. Most of those who will be killed by tobacco in the first half of this century have already begun to smoke. So, these numbers of tobacco deaths could be substantially reduced only by current smokers giving up the habit. In contrast, the extent to which young people henceforth become persistent smokers will affect mortality rates chiefly in the middle or second half of the 21st century."