Extra schooling cuts dementia risk and weakens genetic disadvantage

Longer schooling was linked to a lower risk of dementia, including among people with a high genetic risk, according to a study reported by ERR.

Researchers at the University of Wisconsin-Madison used a 1972 UK law that raised the school-leaving age from 15 to 16. People born in September 1957 or later had to stay in school longer than those born a few months earlier. The researchers analysed data on hundreds of thousands of people and compared the groups’ health in their 60s.

By age 65, dementia was less common among those who had spent longer in school. Each additional year of schooling was associated with a reduction of about 0.88 percentage points in the rate of dementia. The benefit was particularly clear among people with inherited risk factors, such as the APOE4 gene variant. The gap in dementia rates between people at low and high genetic risk fell from 0.18 percentage points to 0.02 percentage points after the additional compulsory school year.

The researchers said longer schooling may improve living conditions overall, including by leading to higher incomes and reducing the risk of diabetes, heart attacks and strokes later in life. These socioeconomic advantages may accumulate over time and help protect the brain. The findings were published in the journal PNAS.