A
study by Langa et al published in JAMA Internal Medicine, reveals that the dementia rate in Americans
65 and older fell over the past 12 years.
The authors used data
from the Health and Retirement Study (HRS) of individuals in the United States
65 years or older from the 2000 (n = 10 546) and 2012 (n = 10 511) waves of the
HRS.
In this study of more
than 21 000 US adults 65 years or older, dementia prevalence declined
significantly, from 11.6% in 2000 to 8.8% in 2012. Interestingly a previous post dated April 2016 reported on a study publishedin NEJM that found a decline in the
incidence of dementia in the Framingham Hearth Study.
The study subjects 56%
of which were females had an average age of 75.0 years in 2000 and 74.8 years
in 2012. Dementia prevalence among those 65 years or older decreased from 11.6%
in 2000 to 8.8%. More years of education was associated with a lower risk for
dementia, and average years of education increased significantly from 11.8
years to 12.7 between 2000 and 2012. An
unexpected finding was that being overweight was also associated with a 30%
decreased risk of dementia. The decline
in dementia prevalence occurred even though there was a significant age- and
sex-adjusted increase between years in the cardiovascular risk profile (eg,
prevalence of hypertension, diabetes, and obesity) among older US adults.
The authors concluded
that the prevalence of dementia in the United States declined significantly between
2000 and 2012.
