Case and Kraftman (2022) clearly summarise evidence relating inequalities based on individual characteristics, such as education and area-based deprivation measures, with all-cause and cause-specific mortality in the UK. The third section of their chapter focuses on how health inequalities develop and why they persist. The emphasis is on early life and childhood factors, such as the uterine environment, birth weight and childhood mental health, that drive later life health disparities. These are crucial issues, but they are very distant in the lifespan from most serious illnesses and death. The median age of death in the UK is now 82.5 years for men and 85.9 years for women. Just under 95% of deaths from all causes take place among people aged 50 and older. Thus, for the large majority of the population, death takes place decades after the factors highlighted by Case and Kraftman; so, in addition to the importance of early life experiences, experiences in the intermediate decades are critical. The largest contributors to socio-economic inequalities in premature death (deaths before the age of 75) are coronary heart disease, chronic obstructive pulmonary disease (COPD) and respiratory and digestive cancers. Analyses of all premature deaths in England between 2003 and 2018 estimate that these four conditions between them make up 46% of deaths attributable to socio-economic inequalities based on the index of multiple deprivation (Lewer et al., 2020). Over the same time period, greater inequalities were observed for deaths due to tuberculosis, opioid use and HIV, but the absolute number of deaths from these conditions was rather smaller.
The diseases that are the primary drivers of socio-economic inequalities in mortality are strongly related to lifestyle factors such as smoking, physical inactivity, dietary choice, poorly managed risk factors (e.g. hypertension) and obesity. As Mackenbach (2019) states, these causes are ‘eminently avoidable’ through better treatment and prevention. Nevertheless, inequalities persist when these factors are taken into account, though estimates of the variation in mortality not explained by lifestyle differ across studies. For example, a longitudinal analysis of the Lifepath project involving individual-level analysis of 48 independent prospective cohort studies, with more than 1.7 million adults followed for an average of 13.3 years, showed that low socio-economic status based on occupational position was associated with mortality independently of smoking, high alcohol intake, physical inactivity, hypertension, diabetes and obesity (Stringhini et al., 2017). The population attributable fraction was greatest for smoking, followed by physical inactivity and then socio-economic status. But a smaller study of the Whitehall II cohort found that socio-economic variations in mortality were largely explained by these behaviours (Stringhini et al., 2010). Another study using UK Biobank concluded that body mass index, blood pressure and smoking accounted for just over one-third of the effects of educational attainment on cardiovascular disease, implying that more than half of the protective effect of education was not explained (Carter et al., 2019).
Findings of this type have several implications, three of which are discussed in this commentary. First, we suggest that serious consideration should be paid to non-traditional adult risk factors that may complement early life factors in contributing to health inequalities. Unlike childhood factors that are fixed in early life, adult experiences are potentially malleable at later ages, so interventions may benefit the health of the current generations of young and middle-aged adults in the 21st century. Second, we address the issue of how socio-economic inequalities in childhood are translated into the health conditions that cause death in later life, focusing on the impact of early life exposures on the mental ill-health of young adults, and its impact on later multimorbidity. Finally, we touch on the relevance of positive psychological characteristics such as positive emotional well-being, optimism and purpose in life, arguing that these malleable factors have the potential partly to ameliorate the adverse effects of low socio-economic status in childhood and adult life.
Cite this as:
Fancourt, D. and Steptoe, A. (2022), ‘The contribution of adult experiences, multimorbidity and positive psychological well-being to social inequalities in health’, IFS Deaton Review of Inequalities, https://ifs.org.uk/inequality/the-contribution-of-adult-experiences-multimorbidity-and-positive-psychological-well-being-to-social-inequalities-in-health