Is Cognitive Decline Related to Education Level?

The Agency for Healthcare Research and Quality released information in January regarding cognitive disorders in the elderly. Cognitive disorders are conditions that hinder a person’s cognitive functioning including reasoning and memory.
In 2007, the percentage of persons age 85 and older reporting one or more cognitive disorders (18.4 percent) was higher than the percentage of persons ages 75- 84 (6.0 percent) and persons ages 65-74 with cognitive disorders (1.1 percent). Interesting but maybe not surprising was how disorders correlated to education level, insurance, and income.

A higher percentage of elderly persons completing less than 12 years of education reported one or more cognitive disorders (8.6 percent) when compared with elderly persons reporting 12 years of education (4.9 percent) and elderly reporting more than 12 years of education (2.7 percent) in 2007.

During 2007, the percentage of elderly persons with Medicare and other public insurance reporting one or more cognitive disorders (10.6 percent) was higher than elderly persons with Medicare and any private insurance (4.1 percent) and elderly persons with Medicare only (5.0 percent).

In 2007, a lower percentage of elderly persons with middle and high income reported one or more cognitive disorders (4.1 percent) than elderly persons that were poor (7.9 percent) or elderly persons that were near poor and had low income (6.7 percent).

In 2007, 5.2 percent of the 38.7 million persons age 65 and older (elderly persons) in the U.S. civilian non-institutionalized population reported having one or more cognitive disorders.
So is education the root cause here? The logic seems to be that better educated people have better jobs and higher income; the ability to afford better insurance and the knowledge to take care of themselves better.