Brain iron deposits are associated with general cognitive ability and cognitive aging

Citation

Penke L, Valdés Hernandéz MC, Muñoz Maniega S, Gow AJ, Murray C, Starr JM, Bastin ME, Deary IJ & Wardlaw JM (2012) Brain iron deposits are associated with general cognitive ability and cognitive aging. Neurobiology of Aging, 33 (3), pp. 510-517.e2. https://doi.org/10.1016/j.neurobiolaging.2010.04.032

Abstract
A novel analysis of magnetic resonance imaging (MRI) scans based on multispectral image fusion was used to quantify iron deposits in basal ganglia and microbleeds in 143 nondemented subjects of the generally healthy Lothian Birth Cohort, who were tested for general cognitive ability (intelligence) at mean ages of 11, 70, and 72 years. Possessing more iron deposits at age 72 was significantly associated with lower general cognitive ability at age 11, 70, and 72, explaining 4% to 9% of the variance. The relationships with old age general cognitive ability remained significant after controlling for childhood cognition, suggesting that iron deposits are related to lifetime cognitive decline. Most iron deposits were in the basal ganglia, with few microbleeds. While iron deposits in the general population have so far been dismissed in the literature, our results show substantial associations with cognitive functioning. The pattern of results suggests that iron deposits are not only a biomarker of general cognitive ability in old age and age-related cognitive decline, but that they are also related to the lifelong-stable trait of intelligence.

Keywords
Cognitive ageing; intelligence; general cognitive ability; iron; hemosiderin; basal ganglia; cognition; MRI;

Journal
Neurobiology of Aging: Volume 33, Issue 3