How premature deaths are linked to social inequality
This research, undertaken by researchers at the National Institute for Health Research (NIHR) and the Wellcome Trust, used data made available via the Office for National Statistics (ONS) Secure Research Service (SRS), which is being expanded and improved with ADR UK funding.
People of a low social position are more likely to die young. Reducing this inequality is a central health policy objective, but progress has been limited.
Led by Dan Lewer of University College London, researchers analysed mortality records of all 2,465,285 premature deaths (defined as those before age 75) in England between 2003 and 2018. This data included the decedent’s age of death, sex, postcode of residence and the underlying cause of death by ICD10 code (International Statistical Classification of Diseases and Related Health Problems). Postcodes were used to derive the decedent’s neighbourhood, defined by ‘lower super output area’ (LSOA), a small area of around 1,500 residents, of which there are 32,844 in England. Deprivation was defined by deciles of the Index of Multiple Deprivation 2015 (IMD), a composite measure including income, employment, education levels, crime, health and availability of services and local environment.
Findings showed premature mortality rates decreased for both men and women and in all deprivation groups. Reductions in absolute mortality rates were greater for more deprived groups, while relative reductions were greater for deprived groups, leading to an increase in Mortality Attributable to Socioeconomic Inequality (MASI). During the study period premature mortality rates decreased for both men and women and in all deprivation groups. Reductions in absolute mortality rates were greater for more deprived groups, whereas relative reductions were greater for less deprived groups, leading to an increase in mortality attributable to socioeconomic inequality.
If everyone in England experienced the mortality rates of the least deprived group, there would have been 877,082 fewer premature deaths between 2003 and 2018. This is an average of one death every nine minutes. Approximately 35.6% (95% CI 35.3% to 35.9%) of premature deaths can be attributed to inequality.
The life table modelling suggested that premature mortality causes an average of 3.3 years lost before age 75 per person. If everyone experienced the mortality rates of the least deprived group, this could be reduced to an average of 2.1 years. Using this method, 36.2% of years of life lost due to premature mortality can be attributed to inequality.
This research provides evidence to allow government and local authorities to prioritise interventions that address these inequalities, associated with so-called upstream factors, such as neighbourhood deprivation, as well as behavioural factors such as alcohol, tobacco and physical activity. Mortality attributable to inequality can be used to monitor inequalities in whole populations and subpopulations, in conjunction with existing measures of health inequality.