Association Between Iron Deficiency and Dementia Risk: AMORIS Study Insights
Overview
This large population-based study from Sweden investigated the longitudinal association between absolute and functional iron deficiency and dementia risk. Findings suggest distinct impacts of iron deficiency types on dementia development, highlighting the importance of iron status in cognitive health among older adults.
Background
Dementia affects approximately 55 million people worldwide, with numbers expected to rise significantly by 2050, imposing substantial economic and healthcare burdens. Iron plays a crucial role in brain metabolism and neuronal function, and iron deficiency is common in older adults. While anemia has been linked to dementia, the specific role of iron deficiency—both absolute and functional—remains unclear. This study addresses the gap by examining these associations longitudinally using the AMORIS cohort.
Data Highlights
Parameter
Definition
Sample Size
Absolute Iron Deficiency
Serum ferritin < 30 µg/L
4,500 individuals
Reference Group
Normal hemoglobin, iron, and TIBC
67,383 individuals
Total Cohort
Age ≥ 50 years with relevant blood tests
70,935 individuals
Key Findings
Absolute iron deficiency was defined by low serum ferritin < 30 µg/L, while functional iron deficiency was characterized by normal ferritin but altered iron and TIBC levels.
The study included 4,500 individuals with iron deficiency and 67,383 with normal iron status as a reference group, all aged 50 years or older.
Individuals were followed for up to 15 years for dementia diagnosis, death, emigration, or end of follow-up.
Adjustments were made for potential confounders including smoking, BMI, and kidney function in sensitivity analyses.
Findings support the hypothesis that iron deficiency, particularly absolute deficiency, may increase dementia risk through mechanisms such as brain hypoxia and white matter lesions.
Clinical Implications
Clinicians should consider screening for iron deficiency in older adults as part of dementia risk assessment, even in the absence of anemia. Differentiating between absolute and functional iron deficiency may guide targeted interventions to potentially reduce dementia risk. Further research is needed to establish causality and evaluate iron supplementation as a preventive strategy.
Conclusion
This study provides important longitudinal evidence linking iron deficiency, especially absolute iron deficiency, with increased dementia risk. Addressing iron status in older populations may represent a modifiable factor in dementia prevention strategies.
References
AMORIS Study/Sweden/2024 -- Association Between Iron Deficiency and Dementia Risk
