First described in 1906 by German psychiatrist and neuropathologist Alois Alzheimer, Alzheimer's has a greater social impact than almost any other disease in the world. It has financial, emotional and organizational consequences for sufferers and their families and communities. Twenty-three years ago, the World Health Organization instituted an awareness day for this important issue. It named 21 September as World Alzheimer's Day, and then extended this to cover the entire month. The event involves doctors, volunteers and local bodies bringing the Alzheimer's debate out into the public domain and increasing awareness of the daily difficulties faced by relatives.

ONE NEW CASE EVERY 3 SECONDS.

The numbers offer little comfort. Alzheimer's is becoming increasingly widespread as global life expectancy rises, with an estimated 10 million new cases each year, one every 3 seconds. By 2050, there are likely to be over 130 million diagnosed cases in the world, 68% of them in countries with moderate to low standards of living. World Alzheimer's Day also encourages governments to focus more attention on the problem, increase awareness, improve diagnosis rates, provide better access to services, and support carers: in other words, not to forget people who forget.