There are inequalities in health between countries and within countries; these are often linked to the wealth of a country, or to a person’s social position within a society.
Because we have so much data on inequalities, they form a convenient starting-point.
Our goal is to describe these patterns of health, and then seek explanations for them.

• Health inequality: generic term referring to systematic differences in health between groups of people, including those that arise naturally and others whose origins lie in social disadvantage.
• Health disparity: subset of inequalities that are probably systematic & arise from social or other disadvantage that may in theory be correctable.
• Health inequity: subset of disparities that are deemed unfair or that stem from an injustice. (Differences in health across age groups may be an inequality; differences across racial groups could be an inequity)
(Note you will find somewhat different usage between
US & British literature)

200
Infant Mortality Rates in 56 Countries, by GNP Per Capita, 1996
150
100
Among poorer countries, infant mortality is very sensitive to variations in GNP, but does not vary above about GNP $10,000 per year.
Different processes operate in poor and rich countries.
50
0
0 5000 10000 15000 20000 25000
GNP per Capita
30000 35000 40000
Source: 1998 World Bank Report

Major Finding: Our health is certainly improving!
Crude and age-standardized mortality rates,
Canada, 1920-2000
Deaths per
1000 population
14
12
10
Standardized
Crude
4
2
0
8
6
1920 1930 1940 1950 1960 1970 1980 1990 2000

But health still varies along a social gradient in rich countries:
Lower-income Canadians live shorter lives than rich ones.
Remaining life expectancy at age 25 in Canada by sex and income quintile, non-institutionalized population, 1991 to 2006
62
60
58
56
54
52
50
48
46
44
42
40
Men
Women
1 2 3 4 5 1 2 3 4 5
Income adequacy quintiles

60
40
20
0
120
100
80
This is not new: Potential Years of Life Lost (All Causes)
England & Wales, 1971 – 1991
Message: overall mortality rates fell over the 20 years, but the class inequality remained. There is a gradient, but the major deficit is for the lowest class.
Occupational
Class
V
IV
III n, m
II
I
1971 1981 1991

• Unemployment & health
– RR 2.1 for unemployment with 5-year total mortality (Morris)
– 10% rise in unemployment → 1.2% rise in mortality (Brenner)
• Some occupations imply direct exposures & hazards; behaviors also implicated (not wearing protective gear)
• Stress & Strain? Karasek’s hypothesis: Low control over work + high demand → strain
– Whitehall study: low perceived job control gave OR = 1.9 for
CVD

Cumulative fetal and infant mortality over time, by maternal education, Québec, 1990-91
M essage: there is an almost two-fold gradient across educational groups.
12
Deaths per
1000 total births
10
8
6
4
0-10 yrs education
11 yrs
12-13 yrs
2
14+ yrs
0
11 16 21 26 31 36 41 46 51 56 61 66 71 76
Weeks since conception
Source: Russ Wilkins, Statistics Canada

The previous slides showed levels of health by levels of social status.
But what is important: absolute status (amount of wealth, prestige, power) that counts, or is it relative status?
Note that in a society where few people are actually starving, there is still a SES-health gradient, so does one’s rank order
(as opposed to actual $$ wealth) somehow matter?
This is the theme of income inequality: maybe societies with unequal wealth are hazardous to our health?

% of income
100
0
L(s)
• L(s) lies below line of equality when income inequality favours the rich
• Gini coefficient is twice the area between the curve and the line of equality
• It is about 0.32 for Canada
(2006)
% of population
100

Gini coefficients for the World
(Note that China and Russia are quite unequal…)
Source: Wikipedia http://en.wikipedia.org/wiki/File:Gini_Coefficient_World_CIA_Report_2009.png

Income Inequality and Life Expectancy in 23 wealthy countries
(Data from Equality Trust www.equalitytrust.org.uk)
82.00
Japan
81.00
80.00
79.00
78.00
77.00
76.00
75.00
3.00
Sweden
Norway
Spain
Belgium
Austria
D
Finland
F
NL
Canada
CH
Greece
Is
Italy
Australia
NZ
UK
4.00
Denmark
5.00
Ireland
6.00
7.00
Income Inequality
8.00
Singapore
USA
Portugal
(r = –0.4)
9.00
10.00
CH–Switzerland D–Germany Is–Israel NL-Netherlands NZ–New Zealand
UK–United Kingdom USA-United States of America

Occupational Class Differences in IMR in
England & Wales, Compared to Sweden
OK: so what on earth is Sweden doing differently?
Deaths per 1000 live births
16
14
12
10
8
6
4
2
0
I II IIIN IIIM IV V Single parents
England
& Wales
Sweden

• Technical: which health indicators to use? Which indicators of social status?
• Scale of analysis seems very important: individual, community, or societal?
• Is SES merely a proxy for familiar risk factors (poorer people smoke more and have worse diets)?
• What constitutes an explanation? How much is random? How to blend the narrative and the scientific?
• The hierarchy of disciplines: how to harmonize perspectives from different disciplines studying different aspects of the overall picture?