Dementia
Dementia represents one of the greatest challenges associated with population ageing. The term “dementia” describes a variety of brain disorders, including Alzheimer’s disease, which progressively lead to brain damage and cause a gradual deterioration of a person’s functional capacity and social relations. Despite billions of dollars spent on research into dementia-related disorders, there is no cure, and substantially disease-modifying treatments may only now be emerging.
More than 21 million people in OECD countries are estimated to have dementia in 2021. If current trends continue, this number will double by 2050, reaching nearly 42 million people across OECD countries. Age remains the greatest risk factor for dementia: across the 38 OECD countries, average dementia prevalence rises from 2.2% among people aged 65-69 to nearly 42% among people aged 90 or older. This means that as countries age, the number of people living with dementia will also increase – particularly as the proportion of the population over 80 rises. Already, countries with some of the oldest populations among OECD countries – including Japan, Italy and Germany – also have the highest prevalence of dementia. Across OECD countries on average, 16 people per 1 000 population are estimated to have dementia (Figure 10.8). In eight countries, more than 20 people per 1 000 population are living with a dementia disorder. By 2050, all but five OECD member countries (the Czech Republic, Hungary, Israel, Mexico and the Slovak Republic) will have a dementia prevalence of more than 20 people per 1 000 population, while in five countries (Greece, Italy, Japan, Korea and Spain), more than one in 25 people will be living with dementia.
Even though treatment is not available in most OECD countries, there is much that health and social care systems can do to improve care and the quality of life for 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, and increasing attention is being paid to reducing stigma around dementia, and to adapting communities and care facilities to meet the needs of people with dementia (OECD, 2018[1]).
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 19 OECD countries in 2019, 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, antipsychotic prescribing varies by a factor of six across most OECD countries, from just 16 prescriptions per 1 000 people aged 65 and over in Sweden to 97 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 31% more likely to be prescribed antipsychotic medication than men (Figure 10.9).
People living with dementia have been severely affected by the COVID-19 pandemic. Measures put in place to contain the virus – notably strict bans or limitations on visitors to LTC facilities – dramatically increased social isolation. The longer-term impacts of the containment measures put in place to control the pandemic may have negative impacts on cognitive decline and well-being among many living with dementia.
The prevalence estimates in Figure 10.8 are taken from the World Alzheimer Report 2015, which includes a systematic review of studies of dementia prevalence around the world. Prevalence by country has been estimated by applying these age-specific prevalence rates for the relevant region of the world to population estimates from the United Nations World Population Prospects – 2019 Revision. Differences between countries are therefore driven by the age structure of populations: countries with older populations have more people with dementia. The World Alzheimer Report 2015 analysis includes studies carried out since 1980, with the assumption that age-specific prevalence is constant over time. This assumption is retained in the construction of this indicator, so that fixed age-specific prevalence rates are applied for both 2021 and 2050. Although sex-specific prevalence rates were available for some regions, overall rates were used in this analysis. While more up-to-date estimates of prevalence are available for some regions and countries, the 2015 World Alzheimer Report data was used to ensure consistency in methodology across all OECD countries.
Antipsychotics are defined consistently across countries using Anatomical Therapeutic Classification (ATC) codes. 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.
Sources: OECD analysis of data from the World Alzheimer Report 2015 and the United Nations World Population Prospects.
Source: OECD Health Statistics 2021.