Dementia Rates Are Declining, Yet Inequities Persist

Study Finds That Dementia Rates Are Declining

Dementia is an unfortunate condition faced by many in American families. Aging relatives lose their memories and abilities, while families watch the painful process and do all they can. Care remains expensive and, for many, elusive. With America's population swiftly skewing towards the retiring, aging baby boomers, dementia is a high priority field of medical research. But there is some good news. A new study, funded by the National Institute on Aging and published in the Proceedings of the National Academy of Sciences, discovered that the prevalence of dementia in those over 65 years old has markedly decreased, despite persisting inequities.

Using data from over 20,000 individuals, the team looked to cognitive tests and clinically diagnosed dementia rates. They analyzed the period from 2000 to 2016 to find the change over the years. They discovered something great: age-adjusted prevalence rates of dementia decreased from 12.2% to 8.5% in 2016. This fall of 3.7% is a distinct improvement, and heralds better news for the large portion of the population which is currently around 65. Interestingly, the quickest decline was in the first four years surveyed, between 2000 and 2004. While improvement is shared across racial, gender, and class lines, not all gains were equal.

Prevalence rates for women remain higher, although they saw a greater drop across the period. Black men too saw a larger drop than white men in prevalence rates, but their current overall prevalence remains higher. In short, the inequities of society seem to parallel inequities in rates of dementia. Better education, less smoking, and better cardiovascular health are all thought to contribute to dementia risk. The researchers specifically found they could trace 40% of the improvement among men to a drastic shift in the college-educated population which was over 65 during the studied period. It rose from 21.5% to 33.7%. Among women there was also an increase resulting in 20% of the reduction in dementia prevalence.

“Closing the education gap across racial and ethnic groups may be a powerful tool to reduce health inequalities in general and dementia inequalities in particular, an important public health policy goal,” the author wrote. Most of those over 65 in the period studied would have been members of the Silent generation and the older Baby Boomers, groups which saw about 15% and 24% earning college degrees. However, Millennials clocked in at 39% as of 2018. As with Gen X, but unlike previous generations, women are now more represented in higher education. More people of color are able to attend college now, compared to the 1960s, despite persistent inequity. It remains to be seen how these shifting demographics influence the declining trend of dementia in future years and future studies.