OP37 Projecting patterns of future illness in the population in England to 2040: a microsimulation study

Background

Reliable projections of future population health are needed to help plan health and social care services. This study aims to project patterns of future illness in England from 2019 to 2040 based on current trends in risk factors and life expectancy.

Methods

We used IMPACT_NCD, a validated microsimulation model which combines individual-level data on demographics and risk factors from linked administrative data (Clinical Practice Research Datalink Aurum, Hospital Episode Statistics, and Office for National Statistics mortality) with estimates from peer-reviewed literature on the causal associations between risk factors and disease incidence and mortality. Trends in risk factor exposures (fruit and vegetable consumption, smoking histories, environmental tobacco smoking, alcohol consumption, physical activity, body-mass index, systolic blood pressure, and total cholesterol) were derived from Health Survey for England 2003–2014. We modelled the life-course of individuals in England aged 30+ and their disease history based on their sociodemographic, biological, and behavioural risk factors from 2019 to 2040, assuming a continuation of current trends in risk factors and life expectancy. Our primary outcome was mean Cambridge Multimorbidity Score (CMS) – a weighted index comprising 20 chronic conditions (in order of decreasing weight): dementia, cancer, chronic obstructive pulmonary disorder, atrial fibrillation, heart failure, constipation, epilepsy, chronic pain, stroke, diabetes, alcohol problems, psychosis and bipolar disorder, anxiety and depression, coronary heart disease, connective tissue disorders, irritable bowel syndrome, asthma, hearing loss, and hypertension). To disaggregate changes in population age structure, we present results unstandardised and standardised by sex, age, and deprivation decile, to the 2013 European Standard population. We also present the number of people living with major illness – CMS score≥1.5 (equivalent to the score for cancer). Results are presented with 95% uncertainty intervals. Analyses were conducted in Rv4.2.2.

Results

Preliminary results project a 24% (22%-26%) increase in population ill health between 2019–2040 as measured by unstandardised mean CMS score. Accounting for changing population age structures, this equates to a 5.4% (4.0%-6.8%) rise in standardised average CMS score. The number of people living with major illness was projected to increase by 36% from 2019 levels to 9.1 m (8.8 m-9.5 m) in 2040.

Conclusion

With increases in life expectancy projected to continue, our results suggest that continuing trends in risk factor exposures will lead to an expansion of morbidity, with people spending more years living in ill health. Moreover, a substantial improvement in individual-level risk factors may not be sufficient to halt the future rise in the burden of ill health.