The Flynn Effect is stronger than you think

Despite the lack of effective treatments or preventive strategies, the dementia epidemic is on the wane in the United States and Europe, scientists reported on Monday.

The risk for a person to develop dementia over a lifetime is now 13 percent lower than it was in 2010. Incidence rates at every age have steadily declined over the past quarter-century. If the trend continues, the paper’s authors note, there will be 15 million fewer people in Europe and the United States with dementia than there are now…

Researchers at Harvard University in Cambridge, Mass., reviewed data from seven large studies with a total of 49,202 individuals. The studies followed men and women aged 65 and older for at least 15 years, and included in-person exams and, in many cases, genetic data, brain scans and information on participants’ risk factors for cardiovascular disease.

The data also include a separate assessment of Alzheimer’s disease. Its incidence, too, has steadily fallen, at a rate of 16 percent per decade, the researchers found. Their study was published in the journal Neurology.

In 1995, a 75-year-old man had about a 25 percent chance of developing dementia in his remaining lifetime. Now that man’s chance declined to 18 percent, said Dr. Albert Hofman, chairman of the department of epidemiology at the Harvard School of Public Health and the lead author of the new paper.

Interestingly, this decline seems to be confined to Europe and the United States.  Here is the Gina Kolata piece in the NYT.