Dementia may not be the epidemic we once thought it would be, suggests experts who recently analyzed data on the condition for the Lancet Neurology Journal.

Researchers said the data and figures typically cited for the proportion of people with dementia are "out of date," and the number of sufferers is actually stabilizing in some western European countries, including the UK. Despite these studies being conducted in the 1980s, the National Health Service (NHS) and other health and social care bodies continue to source them into health care plans. "These old studies support the idea of a continuing 'dementia epidemic,' but are now out of date because of changes in life expectancy, living conditions, and improvements in health care and lifestyle," lead study author Carol Brayne, a professor of public health medicine at the Cambridge Institute of Public Health, told NDTV.

Brayne, along with her colleagues from Cambridge University in the UK, Stockholm, Madrid, Bonn and Gothenburg, analyzed the findings of five large studies carried out across Europe, all of which compare both the numbers of people with dementia and the number of people who have being diagnosed at two different points in time.

Researchers found that four out of the five studies showed no increase in prevalence, the number of people with dementia, or incidence, which refers to the number of newly diagnosed cases over the past 20 or 30 years. In fact, the study conducted in the UK showed a drop in the numbers — there were 22 percent fewer people aged over 65 with dementia in 2011 than had been predicted in 1990.

According to Brayne, the dip in numbers coincided with improvements in living standards and education, two factors thought to protect against dementia. Reducing risk factors, such as vascular diseases, high cholesterol and blood pressure, could have also played a role.

"Incidence and deaths from major cardiovascular diseases have decreased in high-income countries since the 1980s," she said. "We are now potentially seeing the results of improvements in prevention and treatment of key cardiovascular risk factors such as high blood pressure and cholesterol reflected in the risk of developing dementia."

This is good news, but it certainly doesn’t mean the end of dementia as a significant issue for the NHS, the authors said. The growing number of elderly people in the world could pose a problem: People aged 85 and older are the fastest growing age demographic, and about 40 percent of them are estimated to be affected by dementia, according to study co-author Yu-Tzu Wu.

That said, some are hesitant to hail the present study as a marker for success.

"While this study is welcome in showing that the percentage of people in particular age groups developing dementia could be getting smaller, the overall number of people with dementia is still set to increase as more people live into their 80s and 90s," chief executive of the Alzheimer’s Society Jeremy Hughes said. Hughes added that with no cure and few effective treatments, the serious economic impacts of dementia still exceed those of cancer and heart disease, making dementia the most critical social and health care challenge in the UK. 

This growing population is certainly not to be ignored, but the authors suggest a “fairly optimistic” view of the future in terms of dementia trends. More funding into preventing dementia through health across the life course should be the focus of efforts, they concluded.

Source: Brayne C, et al. Dementia in western Europe: epidemiological evidence and implications for policy making. The Lancet Neurology. 2015.