Researchers said that dementia may not be the fast-growing epidemic that it was feared to be saying that the number of patients with the condition already stabilizes in the U.K and other western European countries.

The researchers said that the data that are often cited for the proportion of dementia sufferers and the number of new cases are from three decades ago and are now out of date. Nonetheless, the data from the 1980s are still being used by health and social care bodies including the NHS to plan care.

The researchers said that the old studies, which support the notion of a continuing dementia epidemic, are already out of date because of improvements in lifestyle and health care as well as changes in living conditions and life expectancy.

For the new study published in The Lancet Neurology journal, Carol Brayne, from the Cambridge Institute of Public Health, and colleagues looked at the findings of five large studies conducted in the Netherlands, UK, Spain and Sweden, which compared the number of dementia sufferers and those who were diagnosed of the condition over two different periods.

Brayne and colleagues found that of the five studies, four did not show an increase in the prevalence or incidence of new dementia diagnoses over the past two or three decades.

The study conducted in the U.K even showed a drop in number as there were 22 percent less dementia sufferers who were over 65 years old in 2011 compared with what was predicted in 1990.

The study conducted in Spain also showed a drop albeit only in men with the prevalence of dementia in men who were at least 65 years old dropping by about 43 percent between the years 1987 and 1996.

The researchers said that the drop in numbers appear to coincide with improvements in education and living standards, which are believed to provide protection against the condition.

It also occurred with the reduction in risk factors which include vascular diseases. Efforts to reduce blood pressure and cholesterol likewise helped prevent dementia.

"Such reductions could be the outcomes from earlier population-level investments such as improved education and living conditions, and better prevention and treatment of vascular and chronic conditions," the researchers reported in their study, which was published on Aug. 20. "This evidence suggests that attention to optimum health early in life might benefit cognitive health late in life."

Photo: Marcel Oosterwijk | Flickr