Health impacts of a more equal society: a microsimulation study

Abstract

BackgroundSocioeconomic health inequalities persist in England. The gaps in life and healthy life expectancies are more than 15 years between the least and most deprived fifth of areas. The gaps can be explained largely by socioeconomic gradients in diet, smoking, alcohol, physical activity, and disease case fatalities. We aimed to quantify the health impact of a more equal society. MethodsWe used IMPACTNCD, a stochastic dynamic microsimulation that explicitly models the causal relations between exposures (fruit and vegetable consumption, smoking histories, environmental tobacco smoking, alcohol consumption, physical activity, body-mass index, systolic blood pressure, and total cholesterol) and diseases (cardiovascular disease, post-stroke dementia, type 2 diabetes, chronic obstructive pulmonary disease, and common cancers including lung, breast, and colon cancers). We simulated three theoretical scenarios for the years 2021–40 in England. (1) Recent trends in exposures and mortality continue (baseline); (2) in 2021, exposures in the most and second most deprived quintile groups (index of multiple deprivation) match those of the middle quintile (scenario A); and (3) as for scenario A, but additionally, case-fatality rates of the modelled diseases and mortality rates from any other cause match those of the middle quintile group (scenario B). FindingsPreliminary results suggest that under scenario A, approximately 250 000 (95% uncertainty intervals 220 000 to 280 000) disease events would be prevented or postponed, resulting in approximately 1·7 million (1·4 million to 1·9 million) case-years prevented or postponed and about 67 000 (44 000 to 88 000) fewer deaths. The aforementioned outcome equates to 1·7% (1·5 to 1·9) of all incident events, 0·80% (0·66 to 0·91) of all case-years, and 0·94% (0·61 to 1·20) of all deaths. Overall, 390 000 (300 000 to 490 000) quality-adjusted life-years would be gained. Under scenario B, the improved survival rates would prevent or postpone approximately 210 000 (180 000 to 220 000) disease events but would most likely lead to an increase in people living with the modelled diseases of approximately 330 000 (–110 000 to 690 000) case-years. Overall, 1·4 million (1·1 million to 1·7 million) quality-adjusted life-years would be gained. InterpretationSuccessful levelling-up policies would improve health but might increase health-care demand if they lead to improved survival despite the expected incidence reduction. Nevertheless, achieving these gains is politically and socially challenging and likely to be a multigeneration sustained effort. FundingThe Health Foundation.