4. 4
Classifying deaths and diseasesClassifying deaths and diseases
(WHO)(WHO)
• Communicable diseases [Group I]
– Those where death is directly due to the
action of a communicable agent
• Non-communicable diseases
– Diseases [Group II]
• Cancer, diseases of various organ systems (eg
respiratory, cardiovascular etc.), diabetes, mental
health etc.
– External causes (injuries, poisonings and
violence) [Group III]
6. 6
A global problemA global problem
• In 2004 there were 59 million deaths
world-wide
• Non-communicable diseases accounted
for 60% of these deaths and injuries
and violence 10%.
• By 2020 it is estimated that non-
communicable disease will account for
73% of all deaths
GBD 2004 Update, 2008
7. 7
The epidemiologic transitionThe epidemiologic transition
(Omran, 1971)(Omran, 1971)
Change in the balance of disease in
a population
from
communicable diseases
to
non-communicable disease
8. 8
Decline in proportion of totalDecline in proportion of total
mortality due to infectious diseasesmortality due to infectious diseases
England & Wales, 1911-94, by ageEngland & Wales, 1911-94, by age
0
0.1
0.2
0.3
0.4
0.5
0.6
1911 1921 1931 1941 1951 1961 1971 1981 1991
0
0.1
0.2
0.3
0.4
0.5
0.6
1911 1921 1931 1941 1951 1961 1971 1981 1991
MalesMales FemalesFemales
1-141-14
25-4425-44
45-6445-64
65-7465-74
9. 9
Different countries at differentDifferent countries at different
stages of the epidemiologicalstages of the epidemiological
transitiontransition
10. 10
Non-communicable diseases as % of allNon-communicable diseases as % of all
deaths by global regiondeaths by global region
(all ages(all ages))
WORLDWIDE 59%
N.America; W Europe 88%
China, W Pacific, + some SE Asia 75%
Latin America + Caribbean 67%
S E Asia including India 51%
Sub-Saharan Africa 21%
14. 14
Drivers of the epidemiologicalDrivers of the epidemiological
transition in low and middletransition in low and middle
income countriesincome countries
• Population ageing
• Major socio-economic changes (especially
urbanisation)
– changes in risk factors such as diet, physical
activity, smoking etc.
16. 16
GBD 2001 mortality estimatesGBD 2001 mortality estimates
• 107 countries had collected “useable”
information on cause of death from
registration systems
• 55 countries (42 in sub Saharan Africa) no
information on adult mortality
• Estimates based on many assumptions
and extrapolations
17. 17
Global Burden of Disease StudyGlobal Burden of Disease Study
• First GBD study started in 1992 by World
Bank.
• Second GBD study (in collaboration with
WHO) conducted 2001
• Extensive synthesis of all available data to
give set of mortality estimates by age, sex,
region and cause worldwide – for the first
time
• 2001 GBD study covers 135 causes of
death, 17 sub-regions, based on
aggregation of country-level information
18. Global Burden of DiseaseGlobal Burden of Disease
2004 Update2004 Update
(published 2008)(published 2008)
http://www.who.int/healthinfo/glob
al_burden_disease/GBD_report_2
004update_full.pdf
18
19. Distribution of deaths in the worldDistribution of deaths in the world
by sex, 2004by sex, 2004
19
GBD report 2004 update, 2008
20. Mortality rates among men and women aged 15–Mortality rates among men and women aged 15–
59 years, region and cause-of-death group, 200459 years, region and cause-of-death group, 2004
20
GBD report 2004 update, 2008
21. Projected global deaths for selectedProjected global deaths for selected
causes, 2004–2030causes, 2004–2030
21
GBD report 2004 update, 2008
22. Effect of key risk factors onEffect of key risk factors on
mortalitymortality
22
24. Prospective StudiesProspective Studies
CollaborationCollaboration
• Established chiefly to investigate associations of blood
pressure and cholesterol with cause-specific mortality
• Individual data on 900 000 participants without any
previous history of vascular disease from 61 prospective
cohort studies
• 55 000 vascular deaths (34 000 ischaemic heart disease
[IHD], 12 000 stroke, 10 000 other)
30. Usual total cholesterol (mmol/L)
4·0 5·0 6·0 7·0 8·0
1
2
4
8
16
32
64
80-89
70-79
60-69
40-59
Age
Hazardratio
(&95%CI)
Stroke mortality (11 663 deaths) and total cholesterol by ageStroke mortality (11 663 deaths) and total cholesterol by age
32. 32
% of deaths aged 35-69 years% of deaths aged 35-69 years
attributable to smoking in 2000attributable to smoking in 2000
Men Women
Belarus 33% 0%
Russia 33% 3%
Ukraine 32% 3%
Central Asia (8) 23% 4%
Estonia 31% 3%
Latvia 30% 2%
Lithuania 29% 0%
United Kingdom 25% 21%
Germany 29% 11%
Source : http://www.deathsfromsmoking.net/
33. 33
Risk of myocardial infarction increases withRisk of myocardial infarction increases with
every single cigarette smoked per dayevery single cigarette smoked per day
Number of cigarettes smoked per day
OddsRatioofMyocardialInfarction
Never 1-2 3-4 5-6 7-8 9-10 11-12 13-14 15-16 17-18 19-20 >=21
Source : K. K. Teo et al Tobacco use and risk of myocardial infarction in 52 countries in the INTERHEART study
Lancet 368 (9536):647-658, 2006.
INTERHEART study
52 countries
12 461 cases, 14 637 controls
34. 34
Smoking causes more deaths fromSmoking causes more deaths from
cardiovascular disease than cancercardiovascular disease than cancer
Deaths attributed to smoking
among men (all ages) in Russia, 2000
All cancers = 77,000
Cardiovascular disease = 148,000
Source : http://www.deathsfromsmoking.net/
36. 36
Smoking in men in RussiaSmoking in men in Russia
is not decliningis not declining
Rural
Urban
St Petersburgh/Moscow
Source : Perlman et al Tob.Control 16 (5):299-305, 2007
Russian Longitudinal Monitoring Survey
37. 37
Smoking in women in RussiaSmoking in women in Russia
is increasingis increasing
Rural
Urban
St Petersburgh/Moscow
Russian Longitudinal Monitoring Survey
Source : Perlman et al Tob.Control 16 (5):299-305, 2007
43. 43
Marshall BJ,.Warren JR. Unidentified curved bacilli in the
stomach of patients with gastritis and peptic ulceration.
Lancet 1984;1:1311-5.
Marshall BJ, Armstrong JA, McGechie DB, Glancy RJ.
Attempt to fulfil Koch's postulates for pyloric
Campylobacter. Med.J.Aust. 1985;142:436-9.
TheThe Helicobacter pyloriHelicobacter pylori story …...story …...
44. SummarySummary
• Non-communicable diseases are now the most
common cause of death world wide
• Increasing rates in low and middle income
countries because of change in lifestyles
(urbanisation)
• Key risk factors have very large effects
• Interventions are effective and can reduce
burden
• The need to combine results and have large
studies
44
Notes de l'éditeur
Here we see the decline over time in the proportion of mortality at different ages attributable to infections ranging from tuberculosis to diuphtheria, measles and gastro-intestinal infections.
The downward spike in 1918 is because most excess deaths were from pneumonia rather than “influenza”. Rates of pneumonia were much lower than those for infectious diseases either side of the 1918 Spanish flu – making up less than 10% of all deaths among those aged
The sharp decline mid-century is not well understood and is under-researched. The precise role of the introduction and use of anti-biotics is important question.. Mackenbach’s work suggesting that this played a role in the Netherlands at least.
With the decline of infectious diseases life-expectancy in particular becomes more strongly related to the influence of individual behaviours. This is apparent with the widening gap in male to female life-expectancy over the 20th Century which rose from 4 years in 1900 to a peak of just over 6 years in the late 1960s.
The Prospective Studies Collaboration is a collaborative meta-analysis combining data from existing prospective observational studies that recorded both blood pressure and blood cholesterol at baseline and that followed participants for cause-specific mortality. Investigators from around the world have collaborated to combine data from 61 existing prospective studies involving a total of one million participants from Europe, North America, Australia, Israel, China and Japan. During 12.7 million person-years of follow-up there were 120 000 deaths involving more than 55 000 vascular deaths (12 000 stroke, 34 000 ischaemic heart disease [IHD], 10 000 other vascular) and more than 65 000 other deaths.
Figure 1(a): IHD mortality (33 744 deaths) versus usual total cholesterol. Age-specific associations
The hazard ratios are plotted on a floating absolute scale of risk (so each log hazard ratio has an appropriate variance assigned to it.
NOTES: 1 mmol/L lower total cholesterol was associated with about a half , a third and a sixth lower IHD mortality in both sexes at ages 40-49, 50-69 & 70-89, respectively, throughout the main range of cholesterol in most developed countries, with no apparent threshold.
Although the proportional differences in risk decrease with age, the absolute effects of cholesterol on annual IHD mortality rates are much greater at older than at younger ages. For example, the absolute difference in the annual risk of IHD death for a 1 mmol/L difference in total cholesterol was about 10 times greater at 80-89 than at 40-49 years of age.
Figure 4(a). Stroke mortality (11 663 deaths) versus usual total cholesterol. Age-specific associations for total stroke.
Conventions as in figure 1(a).
NOTES: There was a weak positive association between total cholesterol and total stroke mortality at ages 40-59 years, but little association at older ages. When the MRFIT and PSC findings were combined (table 2, webfigure 7), there was a weak positive association with total stroke at ages 40-59 and 60-69 years, but not at older ages.
