The incidence (number of new cases per year) of dementia in the U.S. is apparently declining.
The Framingham Heart Study which has been monitoring 5,200 adults and 5,000 of their off spring since 1975 revealed in February 2016 that the decrease in the rate of new dementia cases was about 20% per decade. The FHS statistics are based on a variety of data sources including questionnaires, medical records, and some direct examinations.
A more recently published study using direct testing of a larger (21,000), more diverse, over 65 year old (average age: 75) U.S. population reveals that the incidence of dementia decreased from 11.6% in 2000 to 8.8% in 2012. In case you want to “study up” for your test, it included:
recalling 10 nouns immediately and then a little later
serially subtracting 7 from 100
counting backwards from 20
Those with more years of education had a lower risk of dementia. (better “test takers” obviously).
Diabetes increased the risk for developing dementia by 39%. Ominously the incidence of diabetes in this studied population increased greatly from 9% in 1990 to 21% in 2012. Despite that, the overall incidence of dementia did decrease. Nobody knows why.
The Framingham Heart Study findings showed that obesity increased the risk of dementia. In this study obese people had a 30% lower risk for dementia, and in fact, underweight people had a 2.5 fold increase in their risk!
As Dr. Denis Evans, one of the study’s authors, said, “Its very complex.”
Speaking of obesity, the holiday eating season is upon us. Almost all of us expect to put on a little weight. Three scientists from three different countries (Finland, France, and U.S.) nicely graphed the average weight gains by month in three countries (Japan, Germany, and U.S.). No surprise. The Christmas season was the winner in all three countries, but Germany was the leader.
That Golden Week spike in Japan at the end of April and first week of May is when 5 of the 9 official Japanese holidays are clustered and most people take the whole week off. (NEJM 375:12 Sept. 22, 2016, p. 1201)
Though the graph is impressive with its spikes and valleys the average weight gain in the U.S. measured in the 10 days after Christmas was only 0.7% or 1.33 pounds; much, much less than the 7-13 pound gains per week or two reported by some cruise ship travelers.
The bad news is that even though half of your holiday weight gain is lost shortly after the holidays, half of the weight gain remains until the summer … and beyond, which resets your baseline weight for the next year.
Oh, well. “Life is short. Have dessert first.”