WEDNESDAY, Oct. 2, 2019 (HealthDay News) -- Income volatility during a 20-year period beginning in young adulthood is associated with worse cognitive function and brain integrity in midlife, according to a study published online Oct. 2 in Neurology.
Leslie Grasset, Ph.D., from Université de Bordeaux in France, and colleagues used data from 3,287 adults (aged 23 to 35 years in 1990) participating in the Coronary Artery Risk Development in Young Adults prospective study. Income volatility was estimated using income data collected from 1990 to 2010 and was defined as the standard deviation of percent change in income and number of income drops of at least 25 percent. Cognitive tests (for 3,287 participants) and brain scans (for 707 participants) were obtained in 2010.
The researchers found that after adjusting for other factors, higher income volatility was associated with worse performance on processing speed (β = −1.09; 95 percent confidence interval [CI], −1.73 to −0.44) and executive functioning (β = 2.53; 95 percent CI, 0.60 to 4.50) but not on verbal memory (β = −0.02; 95 percent CI, −0.16 to 0.11). Similarly, worse performance on processing speed and executive functioning were associated with additional income drops. Microstructural integrity of total brain and total white matter were associated with higher income volatility and more income drops. These findings may not be explained by reverse causation given that all findings were similar when restricted to those with high education.
"While our study does not prove that drops in income cause reduced brain health, it does reinforce the need for additional studies examining the role that social and financial factors play in brain aging," Grasset said in a statement.