The hazards of smoking
and the benefits of stopping
The hazards of smoking
and the benefits of stopping
• This presentation provides evidence from the UK and
the USA, where the health effects of smoking have been
studied over a long period, but these findings apply to
many other countries
• Particular emphasis is given to the risk of death
in middle age (defined as ages 35-69)
• Available on www.deathsfromsmoking.net
Main messages for the individual smoker
•
The risk is big: about half are killed
•
Those killed in middle age lose many years
•
Stopping smoking works
– Even in early middle age, those who stop (before they
have lung cancer or some other fatal disease) avoid
most of their risk of being killed by tobacco
– Stopping before middle age works even better
www.deathsfromsmoking.net
Stopping smoking: avoiding lung cancer
Continued smoking:
16% dead from lung cancer
15
10
% dead from
lung cancer
Stopped age 50: 6%
5
Cumulative risk at
UK male 1990 rates
BMJ 2000; 321: 323-9
Stopped age 30: 2%
Never smoked: <1%
0
45
55
65
Age
75
Delay between cause and effect:
cigarettes, then lung cancer deaths
+
1,000
cigarette
consumption
10
Cigarettes
per adult
per day
Lung cancer deaths
per million per year
500
lung
cancer
5
lung
cancer
0
0
USA:
1900
1920
1940
1960
1980
2000
Long-term study of persistent smoking
• UK men born in the 20th century: first population in the
world exposed to really prolonged cigarette smoking
• They were studied for 50 years by Richard Doll
• Source: “Mortality in relation to smoking:
50 years’ observations on male British doctors”
Doll R, Peto R et al. BMJ 2004; 328: 1519-28
www.deathsfromsmoking.net
Study of smoking and death
in male British doctors
• Asked all UK doctors in 1951, and periodically thereafter,
what they themselves smoked
• Recorded all deaths for 50 years (1951-2001)
• Main findings (for men born in the 20th century)
– Smokers lose, on average, 10 years of healthy life
– Stopping smoking works
www.deathsfromsmoking.net
Survival to age 70 and beyond:
effect of smoking in male British doctors
97
100
91
94
10
80
81
Non-smokers
81%
years
59
% survival
from age 35
60
10
58%
Cigarette
smokers
years
40
24
26
20
4
0
40
50
60
70
Age
80
90
2
100
Effect of stopping smoking at about age 40
100
80
% survival
from age 40
Cigarette
smokers
Ex-smokers stopped at 35-44
and gained about 9 years
60
40
Non-smokers
20
0
40
50
60
70
Age
80
90
100
United Kingdom, 1950-2002
Decrease in smoking prevalence
80
• In 1950, about 80%
of UK men smoked
% smoked
70%
• In 1970, UK male
death rates from
smoking were the
worst in the world
60
%
at ages
35-59
50%
40
% smoked
28%
26%
20
0
1950
1960 1970 1980 1990 2000
• 1970-2000, decrease
in male death rates
from smoking was the
best in the world
United Kingdom, 1970
Looking back to 1970 death rates:
of 100 men aged 35 …
• 42 would have died in middle age*
• 20 of these 42 deaths would have been from smoking
20
42%
www.deathsfromsmoking.net
*risks at year 1970
death rates for ages 35-69
United Kingdom, 1950-2000
Male death in middle age: changing hazards*
Smoking
All causes
15
44%
43%
1950
1955
18
1960
42%
19
1965
20
1970
20
17
1975
1980
42%
39%
16
1985
37%
35%
14
1990
11
1995
2000
43%
8
6
31%
28%
25%
www.deathsfromsmoking.net
*risks at period-specific
death rates for ages 35-69
Poland, 1955-2000
Male death in middle age: changing hazards*
Smoking
1955
1960
1965
1970
1975
1980
All causes
44%
6
40%
8
39%
9
41%
12
41%
13
1985
19
1990
1995
2000
46%
16
46%
47%
20
19
16
www.deathsfromsmoking.net
45%
41%
*risks at period-specific
death rates for ages 35-69
Main messages for the individual smoker
• The risk is big: about half are killed
• Those killed in middle age may well lose
10, 20, 30 or more good years
• Stopping smoking works
www.deathsfromsmoking.net
Richard Doll (1912-2005), who stopped smoking cigarettes at age 37,
photographed aged 91 at the 2004 BMJ press conference
on the 50-year results from his study of British doctors
Michael Crabtree, copyright Troika Photos
Deaths from smoking: an electronic resource
www.deathsfromsmoking.net
Published by
International Union Against Cancer (UICC), Geneva: Switzerland, 2006
Funded by
Clinical Trial Service Unit & Epidemiological Studies Unit (CTSU), University of Oxford
International Union Against Cancer (UICC)
Fogarty International Center, US NIH
UK Medical Research Council
Cancer Research UK
Project team
Project management
Advice and support
Design
Richard Peto, Judith Watt, Jillian Boreham
Sinéad Jones
Steve Woodward, Konrad Jamrozik, Lesley Walker, Trish Cotter
bwa-design.co.uk