Workers who consistently earned low wages see their memory decline “significantly faster” in older age compared to those who never earned low wages toward the end of their career, according to a new study this week from Columbia University’s Mailman School of Public Health. 

How much faster? For every decade, people with a history of low wages experienced just over one extra year of cognitive aging, researchers found. 

“Our research provides new evidence that sustained exposure to low wages during peak earning years is associated with accelerated memory decline later in life,” Katrina Kezios, the study’s lead author and a postdoctoral researcher at Columbia, wrote in a statement. 

Researchers defined a low wage as any hourly wage below two-thirds of the federal median wage for that year. 

Using that definition, they grouped records from a previous study of 2,879 participants born between 1936 and 1941 into three categories: never earned low wages, intermittently earned low wages, or always earned low wages from 1992 to 2004, when they would be between 51 and 68 years old. The records were pulled from the Health and Retirement Study, a representative sample of 20,000 Americans over age 50. 

Then the team looked at how those participants saw their memory decline over the 12 years after they retired. Over that time period, people who continually worked low-wage jobs toward the end of their life suffered one more year of cognitive decline than those who did not work low-wage jobs. 

The study’s findings were presented this week at the Alzheimer’s Association International Conference, and will soon be published in the American Journal of Epidemiology. The study adds to a growing body of research supporting a connection between low wage earners and disparate health consequences.

“Low-wage jobs have been associated with health outcomes such as depressive symptoms, obesity, and hypertension, which are risk factors for cognitive aging,” the researchers wrote. But until now, they added, “no prior studies had examined the specific relationship between low wages during working years and later-life cognitive functioning.”

How to combat this public health issue? One solution, according to researchers, is to raise the federal minimum wage. 

The researchers pointed out that in the U.S, minimum wage has stayed at $7.25 an hour since 2009 and has failed to keep up with inflation. Meanwhile, the number of low wage earners is substantial. In 2019, the Brookings Institute, a think tank, found that more than 53 million people, almost half of U.S. workers between ages 18 to 64, were employed in low-wage jobs. 

Adina Zeki Al Hazzouri, a senior author on the study and assistant professor of epidemiology at Columbia, said the findings suggest that social policies to improve the financial circumstances of low-wage workers “may be especially beneficial for cognitive health.”

“Future work should rigorously examine the number of dementia cases and excess years of cognitive aging that could be prevented under different hypothetical scenarios that would increase the minimum hourly wage,” she wrote.