Dementia
One of the greatest challenges of population ageing across the world, dementia describes a variety of brain disorders, including Alzheimer’s disease, which progressively lead to brain cells and cause a gradual deterioration of a person’s functional capacity and social relations. Years of research and billions of dollars invested in dementia-related disorders have only recently begun to pay off, with the first treatment for Alzheimer’s disease in decades approved in the United States in July 2023. Even with these promising medical advances, there is no cure, and even disease-modifying treatments are only likely to slow the progression of the condition, with the possibility of concerning side-effects.
More than 21 million people in OECD countries were estimated to have dementia in 2021. If current trends continue, this number could rise by almost 50% by 2040, to nearly 32 million people across OECD countries. Age remains the greatest risk factor for dementia; as countries age, the number of people living with dementia will also increase – particularly as the proportion of the population aged over 80 rises. Already, OECD countries with some of the oldest populations – including Japan, Italy and Germany – also have the highest prevalence of dementia. Across OECD countries on average, 15 people per 1 000 population were estimated to have dementia in 2021 (Figure 10.8). In nine OECD countries, more than 18 people per 1 000 population are living with a dementia disorder. Without further prevention and medical advancements, by 2040, 12 OECD member countries (the Czech Republic, Estonia, Finland, Hungary, Italy, Japan, Latvia, Lithuania, Poland, Portugal, the Slovak Republic and Slovenia) will have a dementia prevalence of at least 25 people per 1 000 population, while in three countries (Japan, Latvia, Slovenia), more than 30 people per 1 000 will be living with the condition.
Even though treatment is not available in most OECD countries, there is much that health and social care systems can do to improve care for and the quality of life of people living with dementia and their families. In recent years, at least 25 OECD countries have developed or announced national plans or strategies for dementia. Increasing attention is being paid to reducing stigma around dementia, and to adapting communities and care facilities to meet the needs of people with the condition (OECD, 2018[1]).
The recent approval of Leqembi (also known as Lecanemab) by the Food and Drug Administration in the United States – and possible future approval of the same treatment, as well as others in the pipeline, in other OECD countries – also drives home the need for countries to ensure that people living with dementia are given a high-quality diagnosis, to enable them to receive treatments that could benefit them. While helping to slow progression of Alzheimer’s disease among people in the early stages of dementia or mild cognitive impairment, the treatment’s resource-intensive method of administration and needs to monitor patients – including biweekly intravenous administration, as well as brain scans to monitor for brain bleeding – also underscores the need for health systems to take stock of how prepared they are both to care for people living with dementia today and to deliver and pay for treatments as they come onto the market in the near future.
Although antipsychotic drugs can reduce the behavioural and psychological symptoms that affect many people with dementia, the availability of effective non-pharmacological interventions – as well as the associated health risks and ethical issues of antipsychotic medication – means that they are only recommended as a last resort. However, inappropriate use of these drugs remains widespread, and reducing their overuse is a policy priority for many OECD countries. Across 15 OECD countries with comparable data, on average more than 5% of adults aged 65 and over received a prescription for antipsychotic medicines. This masks the wide variation in prescribing rates between countries. Excluding Latvia, which has very low figures, antipsychotic prescribing varies by a factor of more than five across most OECD countries, from just 16 prescriptions per 1 000 people aged 65 and over in Sweden to more than 90 prescriptions per 1 000 in Ireland. Moreover, age-standardised rates of antipsychotic prescribing were higher for women than for men in every OECD country. On average across 19 OECD countries, women were 25% more likely to be prescribed antipsychotic medication than men (Figure 10.9).
Dementia prevalence estimates are taken from the Institute for Health Metrics and Evaluation (IHME) Global Burden of Disease Study. Estimates of future dementia prevalence are based on modelling the future prevalence of dementia that can be attributed to key risk factors for dementia (high body mass index, smoking and high fasting plasma glucose), while the prevalence of dementia that cannot be attributed to risks within the Global Burden of Diseases, Injuries and Risk Factors Study (2019) is estimated using a linear regression model that also considers education (Nichols et al., 2022[2]).
Antipsychotics are defined consistently across countries using the Anatomical Therapeutic Chemical (ATC) classification of the World Health Organization (WHO). The numerator includes all patients on the medications register with a prescription for a drug within ATC subgroup N05A. The denominator is the total number of people on the register. Most countries are unable to identify which prescriptions relate to people with dementia, so the antipsychotics indicator covers all people aged 65 and over. Some caution is needed when making inferences about the dementia population, since it is not certain that a higher rate of prescribing among all those aged 65 and over translates into more prescriptions for people with dementia. Nonetheless, measuring this indicator, exploring the reasons for variation and reducing inappropriate use can help to improve the quality of dementia care.
References
[2] Nichols, E. et al. (2022), “Estimation of the global prevalence of dementia in 2019 and forecasted prevalence in 2050: an analysis for the Global Burden of Disease Study 2019”, The Lancet Public Health, Vol. 7/2, pp. e105-e125, https://doi.org/10.1016/s2468-2667(21)00249-8.
[1] OECD (2018), Care Needed: Improving the Lives of People with Dementia, OECD Health Policy Studies, OECD Publishing, Paris, https://doi.org/10.1787/9789264085107-en.
Source: OECD Health Statistics 2023.