Measuring health inequalities

Health inequalities are not solely about differences between poorer and better off groups. They describe the systematic relationship between socio-economic position and health. Health inequalities follow a social gradient. Health inequalities show a stepwise relation to social position in a gradient which correlates higher social class with increased health throughout the different social groups health is related to an individual’s position in society at every level.

A focus on socio-economic differentials rather than social disadvantage, widens the frame of health inequality policy in three major ways. Firstly it searches for the causes of health inequality not in the disadvantaged circumstance and health damaging behaviours of the poorest groups but in the systematic differences in life changes, living standards and lifestyles associated with people’s unequal positions in the socio-economic hierarchy. 

Secondly and in consequence, tackling health inequalities is a population-wide goal. It includes everyone. Framed in inclusive terms, the health gradient approach attracts attention to the composition of a population and the distribution of economic advantage and disadvantage. The size of socio-economic groups as well as their levels of health, matter for reducing the socio-economic gradient of health. Thus the intermediate socio-economic groups lying between the top (professional) and the bottom (unskilled manual) make up the majority of the population. Mortality rates are lower than in the poorest group but the compromised health makes a larger contribution to the toll that socio-economic inequality takes on the health of a population. In consequence focusing on the poorest alone will not reduce the size of gain in life expectancy needed to close the gap.

Lastly reducing health gradients provides a comprehensive policy goal: one that subsumes remedying disadvantages and narrowing health gaps between the broader goal of equalizing health chances across socio-economic groups. To improve the health of poorer groups are necessary elements in a strategy to reduce the socio-economic gradient. But this is insufficient. To reduce the socio-economic gradient, health in other socio-economic groups also needs to improve at a faster rate than in the highest socio-economic group.

Description of relative deprivation and of prosperity across the Kent and Medway population 

The tables and figures below show that poverty exists all over Kent and Medway and is not confined to specific areas. Nevertheless there are major concentrations of deprivation in the Thames-side boroughs of Dartford and Gravesham, in the Medway towns and throughout the coastal east of the county, interspersed with some localised areas of high affluence. The more consistently affluent parts of the county are to be found in Maidstone and the south west quarter of Kent. 

Map 1 - Deprivation status of areas in Kent and Medway

Table 1 - Numbers of Kent and Medway residents, by deprivation status and area

Life expectancy

Life expectancy tells us how long a child born today would be expected to live if they experienced the current mortality rates of the area they were born in throughout their lifetime.

Using the data from IMD 2007 for all the electoral wards in Kent, it is possible to demonstrate a highly significant correlation between relative deprivation and life expectancy across the county as a whole, also for Medway and for many of the district council areas. 

Figure 2 - Rank correlation of deprivation with life expectancy - Kent and Medway 

Table 4 - Percentage changes in life expectancy comparing deprivation quintiles

Comparing 2000 with 2007 it is evident that at the beginning of the period there is a pattern of poorer health as defined by life expectancy for all quintiles relative to the most affluent, but in the later period (2006-08), there has been relative improvement in the intermediate quintiles relative to the most affluent.  However for the most deprived, a pattern of divergence (a widening health gap) has continued throughout this period. This pattern is projected to continue to 2010. [Table 4]

Figure 3 – Life expectancy trends by deprivation status, 3-year averages, Kent & Medway

All age all cause mortality

 All age all cause mortality is the accepted convention for measuring overall health status of communities[

The overall mortality gap between the richest and poorest in Kent and Medway is increasing over time with quintiles two to five converging upon each other but the most deprived quintile becoming increasingly orphaned. 

Deconstructing the trend lines:  What do people prematurely die from and where

The National Health Inequalities Intervention Tool produced by the London Public Health Observatory gives the contribution of specific causes of death to the life expectancy gap and thus in deciles of a year, the life expectancy years that could be gained if the most deprived quintile of residents in each district council area of Kent had the same mortality rate as the average in that district for each. The data within in the tool refers to the period 2001-2005.