Epidemiologi Medicin 6'8' semester Epidemiologisk transition: hjertesygdomme

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Epidemiologi Medicin6.-8. semesterEpidemiolog
isk transitionhjertesygdomme
Lektor Henrik Friis, læge, PhD Afdeling for
Epidemiologi, Institut for Folkesundhedsvidenskab
h.friis_at_pubhealth.ku.dk
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Epidemiologisk transitionhjertesygdomme

• Forelæsning (1 time)
• Epidemiologisk transition hjertesygdomme
• Holdundervisning (2 timer)
• Epidemiologisk transition MONICA-studiet
• Prædiktion af risiko
• Forelæsning (1 time)
• Prædiktion af individuel risiko
  Score/HeartScore

Pensum? se http//pubhealth.ku.dk/epi
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Epidemiologic transition CHDDisposition

• Epidemiologic transition - repetition
• Development transition, stages and models
• E.g. New York, USA
• CHD mortality
• How has it changed over time?
• What were the determinants?
• The role of prevention and case-management
• Primary or secondary prevention

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Development transitions

• Economy transition how we produce
• Hunter-gatherer ? agricultural ? industrial
• Hard physical work ? sedentary life style
• Nutrition transition what we eat
• Nutrient-dense ? cereal-based ? high fat-energy
  diet
• Epidemiologic transition our disease pattern
• ? ? famine/pestilence ? chronic diseases ? ?
• Demographic transition our population structure
• High mortality/fertility ? low mortality/fertility
  

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Stages of transition

• Age of pestilence and famine
• High mortality and fertility
• Life expectancy low (lt40 yrs)
• Age of receding epidemics
• Lower mortality
• Life expectancy increasing (30-55 yrs)
• Age of degenerative and man-made diseases
• Lower mortality, fertility critical to population
  dynamics
• Life expectancy high (70)
• Omran A, 1982

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Models of transition

• Classical e.g. western countries
• Socio-economic and sanitary improvements
• Not health care improvements
• Delayed e.g. developing countries
• Health care little socio-economic -
  improvements
• Less decline in fertility population growth
• Accelerated e.g. Japan
• Socio-economic, sanitary and health care
  improvements
• Omran A, 1982

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Epidemiologic transition
Popkin BM, 2001
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Epidemiologic transition in New York
Famine/pestilence
Receding epidemics
Figure 1
Degenerative diseases
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Epidemiologic transitioncoronary heart disease
(CHD) mortality
How has CHD mortality changed over the last 100
years?
Note CVD CHDstroke CVD cardiovascular
disease CHD coronary heart disease
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Epidemiologic transitionCHD mortality?

• Debate in the 1930-40s Is CHD mortality
  increasing?
• No, it may seem so, but is due to
• reduction in competing causes of death
• lengthened life span
• improved diagnosis
• (Master et al, 1939)
• Yes, due to
• changing living conditions
• (Dublin and Spiegelman, 1949)

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Epidemiologic transitionCHD mortality?

• If yes, why should it has it to due with our
  diet?
• Rabbits feed eggs deposited cholesterol in
  arterial wall
• (Anitschkow, 1913)
• Fat-low diet during WW2 ? transient decline in
  CVD
• (Strøm Jensen, 1951)

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Epidemiologic transitionCHD mortality?

• We have changed our way of living from
• ... an active agricultural people.. to.. a
  nation of sedentary city dwellers who overeat
• so, lets launch
• a campaign of education against overeating,
  which is one of the besetting sins of our
  country

Study the disease frequency, distribution and
determinants
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What are the determinants?Large cohort studies
established

• The Framingham Study, USA, 1948
• Seven Country Study, 1950s
• North Karelia, Finland,1972
• MONICA, WHO, 1982
• Monitoring of Trends and Determinants in
  Cardiovascular Disease
• MRFIT
• Multi-country Risk Factor Intervention Trial

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CHD mortality in UK, 1931-71
Increase from 1930 in men by - age groups
- social classes

• (Marmot et al, 1978)

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The Framingham Study, USA, 1948
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CVD mortality, 1970svariation between countries

• Mortality in 35-64 men, age-standardized
• Coronary hearth disease
• 470 /100.000 in Finland
• 73 /100.000 in Japan
• Cerebro-vascular disease - stroke
• 140 /100.000 in Japan
• 35 /100.000 in Denmark

Note, considerable differences in CHD and stroke
mortality?
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Epidemiologic transition
Note CVD CHDstroke CVD cardiovascular
disease CHD coronary heart disease
What next?
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Obesity in US adults, 1990-2000
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CHD mortality in Denmark 1930-95, males

• How is mortality measured?
• Number?
• Proportion?
• Rate?
• What do we see?

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CVD mortality industrialized countries

• 50 reduction between 1970-2000
• First USA, then other western countries,
• - some still increasing
• Both decline in CHD and stroke
• Both in men and women, black and white
• What can the change in mortality be due to?

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CHD mortality
case management
prevention
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CVD mortalityNorth Karelia, Finland, 1969-82

• Age-standardised
• ? North Karelia
• ? Other Finland

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North Karelia, Finland, 1972
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North Karelia, Finland, 1972
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Explaining the decline in CHD mortality, United
Kingdom

• The CHD mortality rates declined from 1981-2000
• 62 in men
• 45 in women
• 68000 fewer death in 2000
• What was the cause?
• Reduction in CHD incidence?
• Reduction in CHD case fatality?
• Used the IMPACT mortality model to assess the
  contribution of changes in risk factors and
  treatments

(Unal et al, 2004)
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Explaining the decline in CHD mortality, United
Kingdom

• Reduction in CHD incidence? 58
• Smoking 48
• Blood pressure 9
• Cholesterol 9
• Reduction in CHD case fatality? 42
• Secondary prevention 11
• Heart failure treatment 13
• AMI initial treatment 8
• Hypertension treatment 3

(Unal et al, 2004)
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CHD still a leading cause of death in the US ?
1980 38 ? 2001 29
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Individual or population?
Who to target? Those at risk or all?
Risk factor
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Individual or population?
Risk
Risk
Identify those at risk and intervene?
Move the population distribute curve to the left?
Risk
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Risks are not dichotomous
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How is it in developing countries?
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Global mortality from chronic disease
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Infectious OR chronic diseases
Infectious diseases
Chronic diseases
Overnutrition Affluence
Undernutrition Poverty
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Infectious AND chronic diseases
Infectious
Chronic
Undernutrition
Overnutrition
Affluence
Poverty
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Summary

• Disease pattern changes over time
• CHD mortality increased since 1930is
• Due to diet and other life-style factor
• Smoking, overweight, cholesterol, blood pressure
• CHD mortality declined since 1970ies
• Decline in incidence improved prevention
• Decline in case-fatality improved
  case-management
• Still a leading cause of death in industrialized
  countries
• Primary prevention important