Contrary to expectation, the rate of people in the U.S. becoming diagnosed with Alzheimer's dementia is actually decreasing since 2000. Compared to as recently as 1990, the rate of people being newly diagnosed with dementia went down from 11.6% to 8.8%. At the same time, the diagnosis occurred later; the average age of new diagnosis increased from80.7 to 82.4 years old.
This may not sound like a lot, but that's a 24% improvement over time! Next thing is to figure out why.
People at higher risk of heart disease or stroke are generally at higher risk of dementia, such as smokers, diabetics, or people with high blood pressure or high cholesterol or those who are overweight. Yet even as people in the U.S. have more of these conditions than before, we're not seeing the continued surge in dementia that would have been expected. Is it because the conditions are being treated more effectively? Do the medications we use protect against dementia? Are people better educated than before? Does it have to do with people smoking less?
The hope is that figuring out why dementia is decreasing and occurring later leads to better treatment, or even to effective prevention.