Dementia: a new case every seven seconds

One hundred years after the first description of Alzheimer’s disease, a landmark paper on the prevalence of this and other forms of dementia has been published in The Lancet.

UNSW Professor of Psychogeriatrics, Henry Brodaty, is one of 12 international experts who have authored the paper.It finds that the number of people affected by dementia will double every twenty years to 81.1 million by 2040. This assumes there are no changes in mortality and no effective prevention strategies or curative treatments.”Our research found that 24.3 million people currently have dementia,” said Professor Brodaty. “There is one new case every seven seconds, which equates to 4.6 million new cases of dementia every year.”The authors found that while most people with dementia live in developing countries (60 percent in 2001, rising to 71 percent by 2040), the rates of increase are not uniform.”Developed regions start from a high base, but will experience a moderate to proportionate increase in the coming decades,” said Professor Brodaty. “The rate of increase is predicted to be three to four times higher in developing areas. This is because of the low base rate of older people and the rapid ageing of developing countries,” he said. “Changes in lifestyle in developing countries, such as more Western style diets and greater exposure to cardiovascular risk factors, may mean that these figures are conservative so that rates could be even higher.”The authors predict that by 2040, China and western-Pacific countries will have three times more people living with dementia than western Europe. They also found that Latin American countries today have half as many people with dementia (1.8 million) as North America (3.4 million), but by 2040 the numbers will be very similar (9.1 million and 9.2 million, respectively).Professor Brodaty and several other top UNSW researchers, led by Perminder Sachdev and including Tony Broe and Brian Draper have received a $5 million NHMRC grant to study healthy ageing. The five-year study will examine how lifestyle, social interaction, diet, exercise and other factors influence the way people age, both physically and mentally.(Source: University of New South Wales: The Lancet: February 2006.)