Medizinische Universität Graz Austria/Österreich - Forschungsportal - Medical University of Graz
Gewählte Publikation:
Ghadery, C.
Brain iron and cognition in healthy aging
Doktoratsstudium der Medizinischen Wissenschaft; Humanmedizin; [ Dissertation ] Graz Medical University; 2015. pp.
[OPEN ACCESS]
FullText
- Autor*innen der Med Uni Graz:
- Betreuer*innen:
- Schmidt Reinhold
- Schwingenschuh Petra
- Altmetrics:
- Abstract:
- Objective: Brain iron accumulates during aging and has been associated with neurodegenerative disorders including Alzheimer´s disease. MR-based R2* mapping enables the in vivo detection of iron content in brain tissue. We here investigated if during normal brain aging increasing iron load relates to cognitive impairment in region-specific patterns. Methods: We included 336 healthy participants from the Austrian Stroke Prevention Family Study (ASPS-Fam) aged 38 to 86 years. MR imaging and R2* mapping in the basal ganglia and neocortex was done at 3T. Comprehensive neuropsychological testing assessed memory, executive function and psychomotor speed. The associations between R2*-based regional iron content and domain-specific neuropsychological test performance were assessed by adjusted mixed models. To test if iron effects on cognition were mediated by vascular brain lesions or brain atrophy we used simple mediation models for estimating indirect effect sizes. Results: We found the highest iron concentration in the globus pallidus, and pallidal as well as putaminal iron was significantly and inversely associated with cognitive performance in all cognitive domains, except memory. These associations were iron load-dependent. Vascular brain lesions and brain volume did not mediate the relationship between iron and cognitive performance. Conclusion: We conclude that higher R2*-determined iron in the basal ganglia correlate with cognitive impairment during brain aging independent of concomitant brain abnormalities. The prognostic significance of this finding needs to be determined.