Research Type: Deprivation & Inequalities

It is now widely accepted that income poverty is associated with increased morbidity and premature mortality. However, for a number of years now there has been some debate about the additional risk posed to health from an unequal distribution of income within society. A number of potential pathways by which income inequality may affect health status have been identified. These include an assertion that societies that tolerate a more unequal distribution of income are the ones that under invest in human, physical, social and health infrastructure, which may undermine the health system and therefore health status. An alternative psychosocial explanation has suggested that the breakdown of social cohesion in societies with a high degree of income inequality may adversely affect health by increasing stress levels.

Cause-specific mortality, particularly for cancers and heart disease, provide commonly available indicators for policy monitoring. However, defining appropriate population sub-groups of interest has, in the past, normally been limited solely to information provided on death certificates – and coded by the General Registry Office (GRO). In terms of ‘Section 75’ groups (S75) this amounts to reliable information for gender, age and marital status only with information on social class commonly recognised as being neither as reliable nor detailed as census data.

Both Northern Ireland and Scotland have been shown to be more deprived and to suffer higher levels of morbidity and mortality than other regions in the UK. Previous work comparing Scotland to England and Wales showed that even after controlling for deprivation, Scotland still experienced an excess of mortality, a phenomenon which has become known as the “Scottish effect”. To date, no detailed comparisons of the relationship between deprivation and health in Northern Ireland and Scotland have been conducted. However, the recent introduction of longitudinal studies, based on the censuses, in both Northern Ireland and Scotland allow such comparisons to be made.