A new study reveals that brain iron levels, assessed using a specialized MRI technique, can predict cognitive decline years before Alzheimer’s symptoms emerge. Researchers discovered that a higher risk of mild cognitive impairment was linked to increased iron levels in memory-related areas of the brain. The findings suggest that QSM MRI could be an effective method for early detection and a pathway to innovative therapies targeting brain iron.

An innovative MRI technique that detects iron levels in different brain regions may foresee the onset of mild cognitive impairment and cognitive decline in cognitively unimpaired older adults, potentially opening the door to earlier interventions. Radiology, a journal of the Radiological Society of North America (RSNA), published the research findings [1].

Alzheimer’s disease is the primary cause of dementia globally and an increasing public health concern. Positron emission tomography (PET) scans can identify the buildup of abnormal proteins in the brain, tau and amyloid beta, which emerge years before clinical symptoms. Treatments targeting these proteins have limited effectiveness, indicating that other factors may also contribute to cognitive impairment.

In recent years, researchers have been looking into elevated levels of iron in the brain. Iron overload in the brain is known to cause neurodegeneration by aggravating amyloid toxicity, impairing tau protein function, causing oxidative stress (an imbalance between two different types of molecules in your body: free radicals and antioxidants), and leading to nerve cell death. 

What is QSM MRI?

Quantitative susceptibility mapping (QSM), a special MRI technique, is a noninvasive way to measure brain iron.

According to Dr. Xu Li, the senior author of the study, QSM is an advanced MRI technique that has been developed over the past ten years to accurately evaluate tissue magnetic susceptibility. Unlike traditional MR techniques, QSM provides a reliable, non-invasive approach to mapping and quantifying iron levels in patients by detecting subtle differences in iron concentration across various brain regions.

The Study Findings: Brain Iron Levels Predict Cognitive Decline Risk

Dr. Li and colleagues examined QSM MRI in 158 cognitively intact individuals selected from the Johns Hopkins BIOCARD Study, an investigation of the early stages of Alzheimer’s and related conditions. PET data were available for 110 of the individuals.

The researchers collected baseline QSM MRI data from the participants and tracked them for up to 7.5 years. They discovered that a higher risk of mild cognitive impairment, a transitional stage before Alzheimer’s disease, was linked to higher baseline magnetic susceptibility on MRI in the putamen and entorhinal cortex, two brain regions crucial to memory and other cognitive functions. 

Dr. Li indicated that using QSM, they found increased brain iron in specific memory-related areas, which were linked to a higher risk of cognitive impairment and a faster rate of cognitive decline. Participants with higher levels of amyloid disorders were at even greater risk. 

According to Dr. Li, amyloid burden and tissue vulnerability in the putamen and entorhinal cortex were independently linked to the development of mild cognitive impairment. However, they also seemed to have synergistic effects that accelerated global cognitive decline over time. 

If replicated in bigger trials with more diverse patient populations, the findings suggest a role for QSM MRI in the evaluation of dementia patients.

This type of technique, according to Dr. Li, can assist in identifying people who are more likely to acquire Alzheimer’s disease and may help direct early interventions when new treatments become available. Furthermore, brain iron may be a potential therapeutic target besides its role as a biomarker. 

What’s Next?

In the future, the researchers intend to learn more about how brain iron affects Alzheimer’s disease and how it interacts with other pathologies linked to the disease, such as tau and amyloid proteins. Clinical trials may investigate iron-targeted treatments from a therapeutic perspective.

According to Dr. Li, the researchers also hope to improve the QSM technology’s speed, standardization, and accessibility in clinical practice. 

Alzheimer’s Research Association is a non-profit organization dedicated to helping caregivers of Alzheimer’s disease and dementia. We provide the latest information and news about the illness and helpful tips to help caregivers cope with their daily caregiving challenges. We realize the most important thing that a caregiver needs is financial assistance. Therefore, we provide grants to caregivers to ease their financial burden. Caregivers can apply for grants here: https://www.alzra.org/grant-applications/. 

You can also help caregivers in their endeavor by donating as much as possible: https://www.alzra.org/donate-now/.

References

• Chen, L., Soldan, A., Faria, A., Albert, M., van Zijl, P.C., Li, X. and BIOCARD Study Team, 2025. Susceptibility MRI helps predict mild cognitive impairment onset and cognitive decline in cognitively unimpaired older adults. Radiology, 316(3), p.e250513.

• Brain Iron on MRI Predicts Cognitive Impairment, Decline. RSNA Press Release. https://www.rsna.org/media/press/i/2600. Published Online: 9th September, 2025. Accessed: 25th November, 2025.

• Special MRI technique predicts onset of mild cognitive impairment and cognitive decline. News Medical. https://www.news-medical.net/news/20250909/Special-MRI-technique-predicts-onset-of-mild-cognitive-impairment-and-cognitive-decline.aspx. Published Online: 9th September, 2025. Accessed: 25th November, 2025.

• Brain Iron Levels Predict Cognitive Decline Risk. Neuroscience News. https://neurosciencenews.com/brain-iron-cognitive-decline-29673/. Published Online: 10th September, 2025. Accessed: 25th November, 2025.

• Rudy, M. New MRI brain scan predicts Alzheimer’s risk years before symptoms develop. Fox News. https://www.foxnews.com/health/new-mri-brain-scan-predicts-alzheimers-risk-years-before-symptoms-develop. Published Online: 12th September, 2025. Accessed: 25th November, 2025.