A Grauntian perspective A Grauntian perspective on contemporary British on contemporary British

mortalitymortality

Mike Murphy, London School of Economics  

Prepared for symposium: Mortality Past and Present: Celebrating the 350th anniversary of the

publication of John Graunt's Bills of Mortality

Gresham College, Barnard's Inn Hall, London

29 November 2012

Graunt’s legacyGraunt’s legacy• Mortality analysis & Life tables• Sex differentials• Cause of death analysis• Trend analysis• Cause of death classification• Use of administrative data

Mortality analysis & Life tables: Mortality analysis & Life tables: Period Period life expectancy at birth by sexlife expectancy at birth by sex

Years of life expectancy gained by Years of life expectancy gained by age in subsequent decade, England age in subsequent decade, England

and Wales, based on ONS dataand Wales, based on ONS dataMalesMales FemalesFemales

Further expectation of life by age and Further expectation of life by age and year reached age, based on ONS datayear reached age, based on ONS data

MalesMales FemalesFemales

Sex differentialSex differential in period life in period life expectancy at birthexpectancy at birth

Cause of death analysis:Cause of death analysis: Data qualityData quality

" ... all dying thereof die so emaciated and lean (their Ulcers disappearing upon Death) that the Old-women Searchers after the mist of a cup of Ale, and the bribe of a two-groat fee, instead of one, given them, cannot tell whether this emaciation, or leanness were from a Phthisis, or from an Hectic Fever, Atrophy, &c or from an Infection of the Spermatick parts ... ".Graunt J. Natural and political observations mentioned in a following index, and made upon the Bills of Mortality. Facsimile edition. New York: Arno Press, 1975.

Leading causes of death by sex in Leading causes of death by sex in 2011 & 2001, England and Wales2011 & 2001, England and Wales

Early Epidemiological Early Epidemiological Transition?Transition?

14. The second observation is, that of the said 229,250 dying of all diseases, there died of acute diseases (the Plague excepted) but about 50,000 or 2/9 parts.

15. The third observation is, that of the said 229 thousand about 70 died of chronic diseases, which shews (as I conceive) the state and disposition of the country (including as well its food, as air) in reference to health, or rather to longevity ... the chronic diseases shew the ordinary temper of the place, so that upon the proportion of chronic diseases seems to hang the judgment of the fitness of the country for long life.Graunt J. Natural and political observations mentioned in a following index, and made

upon the Bills of Mortality

Leading causes of death by sex and Leading causes of death by sex and age group, England and Wales, 2009age group, England and Wales, 2009

Source: Office for National Statistics

MalesFemales

Age Group Leading causes

Deaths

% of Age

Group Deaths% of Age

Group

1-4Congenital malformations & chromosomal abnormalities 39 16% 34 14%Influenza and pneumonia 14 6% 15 6%

5-19 Land transport accidents 249 22% 80 13%Suicide and injury/poisoning of undetermined intent 100 9%

20-34 Suicide and injury/poisoning of undetermined intent 852 21% 215 12%Land transport accidents 536 13% 115 6%Accidental poisoning 393 10% 89 5%

35-49 Ischaemic heart diseases 1,456 13%Suicide and injury/poisoning of undetermined intent 1,304 11% 363 5%Cirrhosis and other diseases of liver 1,244 11% 602 9%Malignant neoplasms of breast 1,049 15%

50-64 Ischaemic heart diseases 6,531 20% 1,597 7%Malignant neoplasm of trachea, bronchus and lung 3,375 10% 2,536 11%Cirrhosis and other diseases of liver 1,919 6%Malignant neoplasms of breast 2,616 12%

65-79 Ischaemic heart diseases15,46

6 19% 7,394 12%Malignant neoplasm of trachea, bronchus and lung 8,449 10% 5,991 10%

80+ Ischaemic heart diseases17,89

4 17% 21,405 14%

Cerebrovascular diseases10,19

9 10% 20,686 13%Influenza and pneumonia 7,552 7%Dementia and Alzheimer's disease 13,935 9%

Data qualityData quality

10. In brief, when any dead body is found in England, no algebraist, or uncipherer of letters, can use more subtle suppositions and variety of conjectures to find out the demonstration, or cipher, than every common unconcerned person doth to find out the murderers, and that for ever, until it be done.Graunt J. Natural and political observations mentioned in a following index, and

made upon the Bills of Mortality

““There is only one cause of death There is only one cause of death at old ages ...”at old ages ...”

7. … in case a man of 75 years old died of a cough (of which had he been free, he might have possibly lived to ninety) I esteem it little error (as to many of our purposes) if this person be in the table of casualties, reckoned among the Aged and not placed under the title of Coughs. Graunt J. Natural and political observations mentioned in a following index, and made upon the Bills of Mortality

Population AgeingPopulation Ageing18. “In the foregoing observations we ventured to make a standard of the healthfulness of the air from the proportion of acute and epidemic diseases, and of the wholesomeness of the food from that of the chronic. Yet forasmuch as neither of them alone do shew the longevity of the inhabitants, we shall in the next place come to the more absolute standard, and correction of both, which is the proportion of the aged, viz. 15,757 to the total 229,250. That is of about 1 to 15 or 7 per cent.”

“… I conceive, that in countries subject to great epidemic sweeps men may live very long, but where the proportion of the chronic distempers is great, it is not likely to be so; because men being long sick, and always sickly, cannot live to any great age …”

Graunt J. Natural and political observations mentioned in a following index, and made upon the Bills of Mortality

Period life expectancy for men at Period life expectancy for men at 65: by NS-SEC, 1982 to 200665: by NS-SEC, 1982 to 2006

Source: Longitudinal Study, Office for National Statistics

 NS-SEC Period Increase 

1982-86

2002-06

Years Per cent

1 Higher managerial and professional

15.2 18.8 3.6 23.7

2 Lower managerial and professional

15.1 18.2 3.1 20.5

3 Intermediate 13.9 17.5 3.6 25.94 Small employers and own account workers

14.0 17.5 3.5 25.0

5 Lower supervisory and technical

13.4 16.4 3.0 22.4

6 Semi routine 12.9 15.6 2.7 20.97 Routine 12.9 15.3 2.4 18.6

An optimistic view of the future?An optimistic view of the future?

“In recent years, UK life expectancy at birth has been growing at a rate of around a year every five years. For males in the UK, it is the fastest growth in longevity anywhere in the world. If it carries on, British males could become the world’s longest-lived men a few years from now”Mosaic society: Complex changes in UK society bring with them policy challenges Professor Ian Diamond, Chief Executive, Economic and Social Research Council, 2007.

Life expectancy at birth, EU 2009Life expectancy at birth, EU 2009

MalesMales FemalesFemales

Source: WHO HFA Database

Life expectancy at age 65, EU 2009Life expectancy at age 65, EU 2009

MalesMales FemalesFemales

Source: WHO HFA Database

Expectations about life expectancyExpectations about life expectancyA Potential Decline in Life Expectancy in the United States in the 21st Century“as a result of the substantial rise in the prevalence of obesity and its life-shortening complications such as diabetes, life expectancy at birth and at older ages could level off or even decline within the first half of this century.” (p. 1142) S. J. Olshansky, D J. Passaro, R C. Hershow, J Layden, B A. Carnes, J Brody, L Hayflick, R N. Butler, D B. Allison, and D S. Ludwig.New England Journal of Medicine 352;11 March 17, 2005

Ageing populations: the challenges ahead“If the pace of increase in life expectancy in developed countries over the past two centuries continues through the 21st century, most babies born since 2000 … [in] countries with long life expectancies will celebrate their 100th birthdays..” (p. 1139)

Kaare Christensen, Gabriele Doblhammer, Roland Rau, James W VaupelLancet 2009; 374: 1196–1208.

Estimated & projected rate of improvement of Estimated & projected rate of improvement of SDR, England & Wales 1901-2050SDR, England & Wales 1901-2050

Source: Based on ONS data

Estimated annual rate of improvement (%) of Estimated annual rate of improvement (%) of ASMR, England & Wales 1920-2010ASMR, England & Wales 1920-2010

MalesMales FemalesFemales

Source: Based on HMD data

Hypothesised explanations for the Hypothesised explanations for the ‘Golden cohorts’ include:‘Golden cohorts’ include:

• Differences in smoking patterns between generations

• Better diet and environmental conditions during and after the Second World War

• Those born in periods of low birth rate facing less competition for resources as they age

• Benefits from the introduction in the late 1940s of the Welfare State

• Benefits from medical advances which have increasingly affected older people.

Karen Dunnell, 2008, Ageing and Mortality in the UK – National Statistician's Annual Article on the Population. Population Trends 134: 6-23, p. 19

Cohort life expectancy at birth by sexCohort life expectancy at birth by sex

86.7

55.1

7.5

72.5

11.0 12.4 11.1

0

10

20

30

40

50

60

70

80

90

100

Lung cancer(C33,C34)

Upperaereodig.Cancer

(C00-C15)

Othercancer

COPD (J40-J47,J67)

Otherrespiratory

Vasculardiseases(I00-I99)

Othermedical

In 2000, Smoking responsible for:In 2000, Smoking responsible for:

Source: Peto, Lopez, Boreham, Thun (2006)

29.4

5.49.5

18.4

6 6.83.9 4.5

9.5

28.6

12.5

24.521.2 19.8

0

5

10

15

20

25

30

35

Males Females

Percent of deaths in causes Distribution of smoking deaths by cause & sex, all ages (%)

Does smoking provide the best Does smoking provide the best

explanation for observed patterns?explanation for observed patterns?

• There is strong cohort effect for lung cancer (& smoking)

• Cohort approaches provide a better basis for:• elucidating role of smoking on deaths in England

and Wales• investigating cohort effects in adult mortality

• Analysis using 20th and 21st Century Mortality Database England and Wales of deaths by sex, age (35+ yrs) and cause of death in the period 1950-2007.

APC modelAPC modelTo estimate the role of changing patterns of smoking

overall on adult cohort mortality we use an APC formulated as:

For any cause of death

For details, see Carstensen, B. (2006). Age-period-cohort models for the Lexis diagram. Statistics in Medicine, 26:3018-3045.

Murphy, M. & Di Cesare, M. (2012) Use of an age-period-cohort model to reveal the impact of cigarette smoking on trends in twentieth-century adult cohort mortality in England and Wales. Population Studies, ISSN 0032-4728

pcaapc RRRRm

Model characteristicsModel characteristicsDemographically-informed model with constraints:

• Age-specific rates for reference cohort• Relative risk for cohort (RRc), incorporates linear

“drift” component, & constrained to value 1 for reference cohort

• Relative risk for time period (RRp), constrained to average value of 1 over fitting range (& has no linear trend)

• Age, period and cohort functions modelled as cubic splines

Age Period Cohort models for mortality: Age Period Cohort models for mortality: cohorts born 1885-1955, England and Wales cohorts born 1885-1955, England and Wales

The approachThe approach• Most variation can be accounted for by

age and cohort functions, i.e. the period function is approximately constant

• Users are often concerned with the interpretation of current trends, i.e. rates of change

APC – Lung CancerAPC – Lung Cancer

Co

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rt with

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rt with

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ction

po

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For For these causesthese causes, the model , the model

simplifies tosimplifies to

caapc RRm 1 since pRR

lcapcc

srapc mkm assume &

.,constantelyapproximatis where kkk cc

Annual percentage rate of change of Annual percentage rate of change of cohort relative risk for those born 1885-cohort relative risk for those born 1885-

1955, England and Wales1955, England and Wales

Annual change in cohort standardised Annual change in cohort standardised mortality rate for those born 1885-1955, mortality rate for those born 1885-1955,

England and WalesEngland and WalesMalesMales FemalesFemales

Regression of annual change of total cohort Regression of annual change of total cohort mortality on change of lung cancer cohort mortality on change of lung cancer cohort

mortality, actual and fitted values, for those mortality, actual and fitted values, for those born 1885-1955, England and Wales:born 1885-1955, England and Wales:

Conclusions: Improving mortality Conclusions: Improving mortality

in Britain in Twentieth centuryin Britain in Twentieth centuryRate of improvement increasing to present

level of just over 2% p.a. on averageLarge infant mortality improvements over

whole periodInitially little old age mortality improvement;

recently increases at these agesSmoking-related mortality has an major

contribution to explaining mortality change, both sex differentials and to cohort patterns

The future?

Thank youThank you

The final modelThe final modelWe argue that the first term is cyclical (see earlier) and the

second term is long-term monotonic (ETT), which we fit as a linear term leading to the final model for k:

With estimates

)()()( 0ccchdc

dkSDRch

dc

dSDR lclc

  R2 Coefficient 1/Coefficient

Males 0.743 3.286 0.304

Females 0.764 4.636 0.216