Lower quality education increases dementia risk

Education quality was associated with dementia risk later in life, according to findings published in JAMA Neurology.

Yenee Soh, ScD, a postdoctoral research fellow at Kaiser Permanente Northern California in Oakland, and colleagues noted that lower quality education was more common among Black people and may be a contributor to racial disparities in dementia.

“Higher educational quality (eg, teacher salaries, student-teacher ratio, term length) has been found to be associated with higher educational attainment and higher earnings, which in turn can contribute to protective health behaviors for dementia prevention,” Soh and colleagues wrote. “Structural racism decreases investment in schools that serve Black children and limits access to high-quality education and opportunities for educational advancement, a stark example being the history of Jim Crow laws in the U.S. South that segregated schools for Black and white children.”

The researchers collected data from patients in the Kaiser Permanente Northern California health system. Patients were aged 65 years or older by 1996, were born in the United States and identified as non-Hispanic Black or non-Hispanic white. Those who completed a voluntary multiphasic health checkup survey between 1964 and 1972 were included.

Soh and colleagues assessed dementia diagnoses from 1997 to 2019 to identify the risk for diagnosis associated with educational quality. Educational quality was defined by three state-level indicators: school term length, student-teacher ratio and attendance rates. Patients were divided into tertiles based on each indicator’s quality.

In total, 20,778 patients (56.5% women; 81.2% non-Hispanic white) were included for analyses. The largest proportion of patients (41%) had a high school degree or less, with 32.2% attaining at least a college degree, and 26.8% attending trade school or some college. A greater proportion of Black participants (76.2% to 86.1%) were divided into the lowest tertiles compared with white participants (20.8% to 23.3%).

Over the course of follow-up, there were 7,516 (36.2%) dementia diagnoses; 1,515 (7.3%) of patients had no diagnosis, were alive and maintained membership in the health care system at the end of follow-up.

Compared with the lowest tertile of school term length, the high- (HR = 0.79; 95% CI, 0.73-0.86) and medium-quality (HR = 0.92; 95% CI, 0.87-0.97) tertiles were associated with lower odds of dementia. The trend was similar for the student-teacher ratio (high-quality HR = 0.88; 95% CI, 0.83-0.94; medium-quality HR = 0.83; 95% CI, 0.73-0.94) and attendance rates (high-quality HR = 0.8; 95% CI, 0.73-0.88; medium-quality HR = 0.85; 95% CI, 0.8-0.89).

There were no statistically significant differences in dementia risk between non-Hispanic Black and non-Hispanic white patients.

“These findings have important policy relevance, suggesting that state-level investments to improve educational quality matter,” Soh and colleagues wrote. “Additionally, such policy considerations should also address systemic factors that may contribute to unequal distribution of such investments among racial and ethnic minority groups to help to address dementia disparities.”