As the global population ages, the number of people living with dementia is expected to triple from 50 million to 152 million by 2050.

Dementia is an umbrella term for several diseases that are mostly progressive, affecting memory, other cognitive abilities and behaviour and interfering significantly with a person’s ability to maintain the activities of daily living. Women are more often affected than men. Alzheimer’s disease is the most common type of dementia and accounts for 60–70 per cent of cases. The other common types are vascular dementia and mixed forms. "Nearly 10 million people develop dementia each year, 6 million of them in low- and middle-income countries," Director-General of WHO Dr Tedros Adhanom Ghebreyesus said. 

"The suffering that results is enormous. This is an alarm call: we must pay greater attention to this growing challenge and ensure that all people living with dementia, wherever they live, get the care that they need," Dr Tedros said. The estimated annual global cost of dementia is US$ 818 billion, equivalent to more than 1% of global gross domestic product. The total cost includes direct medical costs, social care and informal care (loss of income of carers). 

By 2030, the cost is expected to have more than doubled, to US$ 2 trillion, a cost that could undermine social and economic development and overwhelm health and social services, including long-term care systems. The Global Dementia Observatory, a web-based platform launched by WHO today, will track progress on the provision of services for people with dementia and for those who care for them, both within countries and globally.

It will monitor the presence of national policy and plans, risk reduction measures and infrastructure for providing care and treatment. Information on surveillance systems and disease burden data is also included. "This is the first global monitoring system for dementia that includes such a comprehensive range of data," said Dr Tarun Dua, of WHO’s Department of Mental Health and Substance Abuse. "The system will not only enable us to track progress, but just as importantly, to identify areas where future efforts are most needed." To date, WHO has collected data from 21 countries of all income levels. By the end of 2018, it is expected that 50 countries will be contributing data.