Dementia is becoming more common around the world  – here's what we can do

The G7 Hiroshima Summit, chaired by Japan, one of the most advanced super-aged societies in the world, has come to a close. At the G7 Nagasaki Health Ministers’ Meeting held before the Hiroshima Summit, the ministers issued a joint statement outlining efforts to realize a society where people can live with peace of mind, drawing on the lessons learned from the pandemic of COVID-19. Its inclusion of dementia within this affirmation is noteworthy.

The statement – which outlined agreements to promote research and development to improve health outcomes through prevention, risk reduction, early detection, diagnosis and treatment of dementia – proclaimed that in the field of research and development, potential disease-modifying therapies for various types of dementia, including Alzheimer’s disease, are being developed. It encouraged manufacturers to bring effective, safe and affordable new treatments for dementia to the global market as quickly as possible.

The G7 Nagasaki Health Ministers’ Meeting also provided opportunities, including a symposium encouraging the international community to work together to promote dementia policies. In addition, there was a forum where multiple stakeholders – including representatives of civil society, the research community, industry and the government – came together to discuss innovations in healthcare delivery systems.

In 2021, the World Health Organization (WHO) reported that dementia affects more than 55 million people worldwide, costing the economy $1.3 trillion annually. Approximately 50% of this economic loss is attributed to caregivers, such as family members and close friends, who spend an average of five hours daily caring for and monitoring patients.

WHO has made dementia a public health priority, and the World Health Assembly, to be held immediately after the G7 Hiroshima Summit, will also focus its discussions on future efforts to address the disease.

In Japan, the elderly population as a percentage of the total population reached 29.1% in 2022 and dementia is becoming a serious social issue that cannot be separated from an ageing society. According to a survey on future projections of the elderly population with dementia in Japan, the number of people aged 65 and over with dementia is projected to reach 6.75 million by 2025, or one out of every 5.4 persons will have dementia.

Eisai, a major Japanese pharmaceutical company, announced this month that Health Canada had accepted a new drug submission (NDS) for its Alzheimer’s disease modifier, lecanemabto, co-developed with Biogen. Lecanemabto, which is expected to inhibit the speed of symptom deterioration in patients with early-stage Alzheimer’s disease, was approved by the US Food and Drug Administration (FDA) under the accelerated approval pathway to treat Alzheimer’s disease in January 2023. The drug is also under review in Europe and China and has been designated as a priority review item in Japan.

Also, in March 2023, a team of scientists, including some from the Tokyo Medical and Dental University, announced that they had conducted successful mice experiments to efficiently deliver a drug for Alzheimer’s disease by encasing it in tiny granules. New medications for this type of dementia are expensive to produce but this new technology is expected to lead to the development of drugs that are effective even in small doses.

While new drugs using antibodies to remove abnormal brain proteins, thought to be the cause of Alzheimer’s disease, are being developed one after another, the challenge is that the antibody is too large in its original size and can only reach the brain in small amounts, making the drug inefficient. The technology developed by the scientist’s group has increased the number of antibodies delivered to the brain by a factor of 80 compared to the amount delivered by simply reducing the size of the antibody.

Municipalities are also addressing dementia as part of their community development efforts. In 2017, Obu City in Aichi Prefecture became the first municipality in Japan to enact an ordinance to promote a community free of anxiety about dementia.

In 2007, the city experienced a fatal accident in which a then 91-year-old man with dementia accidentally stepped onto the tracks inside a train station and was hit by a moving train. The man had dementia for many years and the incident happened when his family left him unattended for only a few minutes. This accident helped raise awareness in the city that dementia is an issue to be addressed by the community and society.

Subsequently, Obu City started a health checkup for residents aged 75 and over called the “Platinum longevity health examination.” Unlike conventional health checkups, this checkup focuses on the health of the brain and body, intending to quickly detect the decline in physical and mental functions that occurs with ageing.

Since the ordinance’s enactment, the city has also focused on training dementia supporters. Supporters who take the course have accurate knowledge and understanding of dementia and play a role in supporting people with dementia and their families in the community and their work areas.

The WHO predicts that dementia patients will increase to 78 million by 2030 and 139 million by 2050. Therefore, there are high expectations for developing new and effective treatments to address this issue in Japan and globally. Above all, creating a symbiotic society where no one is left behind and patients and their families can live in peace is an issue that is becoming ever more urgent.