Published Papers

Background From 2020 to 2050, China’s population aged ≥65 years old is estimated to more than double from 172 million (12·0%) to 366 million (26·0%). Some 10 million have Alzheimer’s disease and related dementias, to approach 40 million by 2050. Critically, the population is ageing fast while China is still a middle-income country.

Methods Using official and population-level statistics, we summarise China’s demographic and epidemiological trends relevant to ageing and health from 1970 to present, before examining key determinants of China’s improving population health in a socioecological framework. We then explore how China is responding to the care needs of its older population by carrying out a systematic review to answer the question: ‘what are the key policy challenges to China achieving an equitable nationwide long-term care system for older people?’. Databases were screened for records published between 1st June 2020 and 1st June 2022 in Mandarin Chinese or English, reflecting our focus on evidence published since introduction of China’s second long-term care insurance pilot phase in 2020.

Results Rapid economic development and improved access to education has led to widescale internal migration. Changing fertility policies and household structures also pose considerable challenges to the traditional family care model. To deal with increasing need, China has piloted 49 alternative long-term care insurance systems. Our findings from 42 studies (n = 16 in Mandarin) highlight significant challenges in the provision of quality and quantity of care which suits the preference of users, varying eligibility for long-term care insurance and an inequitable distribution of cost burden. Key recommendations include increasing salaries to attract and retain staff, introduction of mandatory financial contributions from employees and a unified standard of disability with regular assessment. Strengthening support for family caregivers and improving smart old age care capacity can also support preferences to age at home.

Conclusions China has yet to establish a sustainable funding mechanism, standardised eligibility criteria and a high-quality service delivery system. Its long-term care insurance pilot studies provide useful lessons for other middle-income countries facing similar challenges in terms of meeting the long-term care needs of their rapidly growing older populations.

Background Recent evidence suggests dementia incidence rates are declining in high-income countries. However, data for the trend after 2010 are scarce. We examined the temporal trend in England and Wales from 2002–2019, considering bias and non-linearity.

Methods We used population-based panel data linked to the mortality register across wave 1 (2002–2003) to wave 9 (2018–2019) of the English Longitudinal Study of Ageing, representing initially non-institutionalised adults ≥50 years old. Uniform standard criteria based on cognitive and functional impairment were used to ascertain incident dementia cases. Crude incidence rates were determined in seven overlapping initially dementia-free sub-cohorts followed over four years. We examined the temporal trend of dementia incidence according to age, sex and education attainment. We estimated the age- and sex-adjusted trend of dementia incidence with Cox and multi-state models. Restricted cubic splines allowed for potential non-linearity.

Results 19 806 people were included in the study. Crude dementia incidence declined from 2002 to 2008 (8.7 to 7.4 per 1000 person-years). The rate increased from 2008 to 2019 (7.4 to 10.3 per 1000 person-years). Adjusting for age and sex, and accounting for missing dementia cases due to death, estimated dementia incidence declined by 28.8% from 2002 to 2008 (incidence rate ratio 0.71, 95% CI 0.58–0.88), and increased by 25.2% from 2008 to 2016 (incidence rate ratio 1.25, CI 1.03–1.54). The higher education group had a sharper decline of dementia incidence from 2002 to 2008, and a smaller increase after 2008.

Conclusion Dementia incidence may not be declining. There was a rebound after 2008 in England and Wales. If the upward dementia incidence trend continues, along with population ageing, the burden on health and social care may be large. The burden may be considerably larger than estimated on the basis of a linearly declining dementia incidence trend.

Background Dementia incidence declined in many high-income countries in the 2000s, but evidence on the post-2010 trend is scarce. We aimed to analyse the temporal trend in England and Wales between 2002 and 2019, considering bias and non-linearity.

Methods Population-based panel data representing adults aged 50 years and older from the English Longitudinal Study of Ageing were linked to the mortality register across wave 1 (2002–03) to wave 9 (2018–19) (90 073 person observations). Standard criteria based on cognitive and functional impairment were used to ascertain incident dementia. Crude incidence rates were determined in seven overlapping initially dementia-free subcohorts each followed up for 4 years (ie, 2002–06, 2004–08, 2006–10, 2008–12, 2010–14, 2012–16, and 2014–18). We examined the temporal trend of dementia incidence according to age, sex, and educational attainment. We estimated the trend of dementia incidence adjusted by age and sex with Cox proportional hazards and multistate models. Restricted cubic splines allowed for potential non-linearity in the time trend. A Markov model was used to project future dementia burden considering the estimated incidence trend.

Findings Incidence rate standardised by age and sex declined from 2002 to 2010 (from 10·7 to 8·6 per 1000 person-years), then increased from 2010 to 2019 (from 8·6 to 11·3 per 1000 person-years). Adjusting for age and sex, and accounting for missing dementia cases due to death, estimated dementia incidence declined by 28·8% from 2002 to 2008 (incidence rate ratio 0·71, 95% CI 0·58–0·88), and increased by 25·2% from 2008 to 2016 (1·25, 1·03–1·54). The group with lower educational attainment had a smaller decline in dementia incidence from 2002 to 2008 and a greater increase after 2008. If the upward incidence trend continued, there would be 1·7 million (1·62–1·75) dementia cases in England and Wales by 2040, 70% more than previously forecast.

Interpretation Dementia incidence might no longer be declining in England and Wales. If the upward trend since 2008 continues, along with population ageing, the burden on health and social care will be large.

Funding UK Economic and Social Research Council.

Background There is uncertainty around the health impact and economic costs of the recent slowing of the historical decline in cardiovascular disease (CVD) incidence and the future impact on dementia and disability.

Methods Previously validated IMPACT Better Ageing Markov model for England and Wales, integrating English Longitudinal Study of Ageing (ELSA) data for 17,906 ELSA participants followed from 1998 to 2012, linked to NHS Hospital Episode Statistics. Counterfactual design comparing two scenarios: Scenario 1. CVD Plateau—age-specific CVD incidence remains at 2011 levels, thus continuing recent trends. Scenario 2. CVD Fall—age-specific CVD incidence goes on declining, following longer-term trends. The main outcome measures were age-related healthcare costs, social care costs, opportunity costs of informal care, and quality adjusted life years (valued at £60,000 per QALY).

Findings The total 10 year cumulative incremental net monetary cost associated with a persistent plateauing of CVD would be approximately £54 billion (95% uncertainty interval £14.3-£96.2 billion), made up of some £13 billion (£8.8-£16.7 billion) healthcare costs, £1.5 billion (-£0.9-£4.0 billion) social care costs, £8 billion (£3.4-£12.8 billion) informal care and £32 billion (£0.3-£67.6 billion) value of lost QALYs.

Interpretation After previous, dramatic falls, CVD incidence has recently plateaued. That slowdown could substantially increase health and social care costs over the next ten years. Healthcare costs are likely to increase more than social care costs in absolute terms, but social care costs will increase more in relative terms. Given the links between COVID-19 and cardiovascular health, effective cardiovascular prevention policies need to be revitalised urgently.

Objectives To compare dementia prevalence and how it varies by socioeconomic status (SES) across the USA and England.

Design Population-based comparative study.

Setting Non-Hispanic whites aged over 70 population in the USA and England.

Participants Data from the Health and Retirement Study and the English Longitudinal Study of Ageing, which are harmonised, nationally representative panel studies. The sample includes 5330 and 3147 individuals in the USA and England, respectively.

Main outcome measures Between country differences in age-gender standardised dementia prevalence, across the SES gradient. Dementia prevalence was estimated in each country using an algorithm based on an identical battery of demographic, cognitive and functional measures.

Results Dementia prevalence is higher among the disadvantaged in both countries, with the USA being more unequal according to four measures of SES. Overall prevalence was lower in England at 9.7% (95% CI 8.9% to 10.6%) than the USA at 11.2% (95% CI 10.6% to 11.8%), a difference of 1.4 percentage points (pp) (p=0.0055). Most of the between country difference is driven by the bottom of the SES distribution. In the lowest income decile individuals in the USA had 7.3 pp (p<0.0001) higher prevalence than in England. Once past health factors and education were controlled for, most of the within country inequalities disappeared; however, the cross-country difference in prevalence for those in lowest income decile remained disproportionately high.

Conclusions There is inequality in dementia prevalence according to income, wealth and education in both the USA and England. England has lower dementia prevalence and a less steep SES gradient. Most of the cross-country difference is concentrated in the lowest SES group, which provides evidence that disadvantage in the USA is a disproportionately high risk factor for dementia.