In the news: Is the rate of dementia decreasing?

plaques and tanglesResearch reported at the Alzheimer’s Association International Conference (AAIC) 2013 suggest that the risk of developing dementia in the United Kingdom may be lower than anticipated. Here’s a breakdown of the research:

The claim
Later-born populations have a lower risk of prevalent dementia than those born earlier in the past century.

Background and methodology
In 1989 and 1994, investigators did baseline interviews of 7,635 people aged 65 years and older in geographic areas of England (CFAS I). The results were then used to estimate dementia prevalence, predicting that 8.3% of the population aged 65+ would have dementia two decades later. Between 2008 and 2011 scientists revisited the same geographic areas to provide geographical and generational comparison. This time, they interviewed 7,796 people aged 65 and older and found that prevalence was in fact lower than predicted at 6.5% of the population.

Beyond the headline
It is certainly possible that older adults are living brain-healthier lives. Whether or not that has an impact on the number of people with dementia, we simply do not know yet. However, even if the percentage of new cases in the population is going down (and we don’t know for certain that it is) because the older population is growing at such a fast rate, dementia prevalence – that is, the total number of people with the disease – is continuing to rise. In other words, it is likely that prevalence is not going down but it could be increasing at a slightly slower pace. In addition, this study did look at all dementias, not specifically at Alzheimer’s disease.

The bottom line
This particular study uses a different methodology compared to current U.S. prevalence studies,and it is not expected to have implications for dementia prevalence estimates in the U.S.

Helpful information related to this story

News from the Alzheimer’s Association International Conference

Know the 10 Signs of Alzheimer’s disease

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