September 21 is World Alzheimer's Day. Worldwide nearly 35.6 million people live with dementia. This number is expected to double by 2030 (65.7 million) and more than triple by 2050 (115.4 million). Dementia affects people in all countries with more than half (58%) living in low- and middle-income countries. By 2050 this is likely to rise to more than 70%. Treating and caring for people with dementia currently costs the world more than US$ 604 billion per year. This includes the cost of providing health and social care as well the reduction or loss of income of people with dementia