Some good news in the ongoing battle with Alzheimer’s disease: several recent studies indicate that rates of Alzheimer’s and other types of dementia have decreased significantly in the past 15 to 20 years.
Alzheimer’s disease is the most common form of dementia, a general term for memory loss and loss of other cognitive abilities serious enough to interfere with daily life. Alzheimer’s disease accounts for over 50% of all dementia cases. Mixed dementia, such as Alzheimer’s and vascular dementia, is also a very common but under-reported condition.
A Decline of 24% in Alzheimer’s Disease Prevalence
The latest study, published in JAMA Internal Medicine, surveyed over 21,000 US adults 65 years or older taking part in the US Health and Retirement Study for dementia conditions. The study results showed a remarkable decline in dementia prevalence from 2000 to 2012:
The reasons for this positive decline coalesce around three key themes:
- Rising levels of education and cognitively stimulating professions
- Better control over cardiovascular risk factors (esp. chronic hypertension)
- Changes in lifestyle patterns (esp. abstaining from smoking)
Routine physical exercise and a brain healthy diet are also associated with a lower overall risk of dementia.
But With Some Notes of Caution
While this reported decline in Alzheimer’s and dementia rates is encouraging, there are many reasons to not prematurely declare that the tide is turning.
First, the decline in prevalence has only been verified in North America and Europe. Recent statistics indicate that dementia prevalence rates are increasing in Asia, the Middle East, and Africa.
Also, since the Baby Boom generation is now moving into solidly into the 65+ category, the absolute number of people with dementia in North America and Europe will continue to rise for at least the next 40 years.
At the Alzheimer’s Association annual conference this year, there was some interesting research on Alzheimer’s prevention strategies – read the summary here.