Disrupted brain blood flow tied to poorer cognitive function in MS
Researchers say abnormal process could serve as imaging signal
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Cognitive issues are common in MS.
- A study linked disrupted brain-blood flow matching to cognitive impairment and disability in multiple sclerosis.
- Abnormal prefrontal blood flow and brain activity ratios correlated with lower scores on standard cognitive tests among patients.
- Further research is needed to determine if improving neurovascular coupling can improve cognitive outcomes.
Altered neurovascular coupling (NVC), the process that matches brain activity with the blood flow needed to support it, is associated with poorer cognitive function and greater disability in people with multiple sclerosis (MS), a study found.
The most consistent finding was an abnormal balance between blood flow and spontaneous brain activity in the left medial prefrontal cortex (mPFC), a brain region involved in advanced cognitive skills.
“These findings suggest altered NVC in MS, with regional prefrontal abnormalities representing the most robust and clinically relevant finding,” the researchers wrote. “Regional prefrontal NVC abnormalities may provide a potential imaging correlate of cognitive performance in MS.”
The study, “Prefrontal Neurovascular Coupling Abnormalities Associated With Cognitive Performance in Multiple Sclerosis,” was published in CNS Neuroscience & Therapeutics.
Cognitive problems are common in people with MS and can develop early in the disease course, affecting daily activities and quality of life. However, the biological mechanisms underlying cognitive impairment in MS are not fully understood.
NVC disrupted in MS
Normal brain function depends on a constant match between the activity of nerve cells and the blood flow that supplies them with oxygen and nutrients. This process — NVC — relies on coordinated communication between nerve cells and nearby blood vessels. In MS, inflammation and damage to the brain may disrupt NVC, potentially affecting cognitive function.
To learn more, researchers in China examined available data from 97 MS patients and 83 healthy controls matched for age, sex, and education to assess whether impaired NVC may be related to cognitive performance in MS.
Participants with MS had a median disease duration of about three years, and the majority (89.7%) had relapsing-remitting MS (RRMS), the most common form of MS. Almost 80% were receiving disease-modifying therapies (DMTs).
MS patients had significantly impaired cognitive function compared with healthy controls, as seen by significantly lower scores in three standard cognitive tests: the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE), which screen for problems in memory, language, attention, and thinking; and the Symbol Digit Modalities Test (SDMT), which evaluates how quickly a person can process and respond to information.
In imaging analysis, participants with MS also had significantly lower NVC than healthy controls, as well as higher blood flow to brain activity ratio in the mPFC. A higher ratio means blood supply is disproportionately high relative to neuronal activity.
Further analysis demonstrated that the blood flow-to-brain activity ratio in the mPFC was associated with clinical and cognitive measures in people with MS. Specifically, higher ratios in the left mPFC were associated with poorer performance on the MoCA and SDMT tests, as well as greater disability measured by the Expanded Disability Status Scale. A higher ratio in the right mPFC was also associated with lower SDMT scores.
“The clinical relevance of the mPFC finding is supported by its associations with both cognition and disability,” the researchers wrote. “This is particularly important because the mPFC is a key hub for higher-order cognitive processing and large-scale network integration.”
The main findings remained unchanged after additional analyses that accounted for other measures of neuronal activity, MS lesion volume, gray matter volume, disability levels, and DMT status. They also did not change when only patients with RRMS were included in the analyses.
While the findings suggest “multilevel NVC alterations in MS,” further studies are needed to clarify its prognostic relevance and determine whether improving NVC leads to better cognitive outcomes in MS, the researchers concluded.
Karen Sproule
In 2010 I had the CCSVI procedure that Dr. Zamboni from Italy, developed.
My left neck vein was blocked so I didn’t have proper blood flow. Postop i was symptom free about 5 years, as well I have not had a single migraine since the procedure.
MaryJane Harris
I agree this happened to me 15years ago i had been diagnosed with hypo-plasia ie narrow jugular veins after an ultrasound for ccsvi later i had a venoplasty performed on my 1mm left IJV and 3mm wide on the right IJV by Dr Mandato in Sept 2011 at the hospital in Albany NY which ballooning expanded the blood flow to both my jugular veins and within an hour i was out of my wheelchair and could walk again. No cane needed no more head pain or seizures. I still have MS fatigue and numbness occasionally but you would think this increased blood flow solved the majority of my symptoms. It has been 15 years and i am a testament to MS being a neuro-vascular disease and that improving blood flow using daily coated aspirin and high dose Vitamin D to reduce inflammation and keep my blood does work for so many of us with malformed jugular veins
This latest research confirms what the vascular surgeon Dr Paulo Zamboni discovered in 2009 with not only his wife with MS but over 100 patients at his hospital in Italy. Yay for good research
Tina Helart
Hi. I'm just wondering when some of these same studies for RRMS will be done for PPMS. There is so much information out there for RRMS, which is great, and so little for PPMS. We are so few. That shouldn't be a reason why there is less research. Just sayin.
rosemary stewart
i have had ms since 1999.i am now 71.i have drop foot bad,and use a walker and scoter for far walking lke shopping.
rosemary stewart
glad to be here i feel i need friend.guess everyone thought they could catch it so they left. i am 71 i use a walker and have drop foot.
Neil Reynolds
I am affected by late onset primary progressive Multiple Sclerosis and am interested in your advice on how to improve my cognitive functioning as I have been lucky to the current condition but have had some indications of issues with my short attention span and memories?
Gerquanti Hambrick
I am among those experiencing cognitive challenges. I recently underwent a memory assessment that provided significant insight into my cognitive function and recall abilities. The results are extensive—a humorous aside—but they effectively illustrate my thought processes and memory retention patterns.
Sandra Kay
Sounds slightly familiar to Dr Zambini's CCSVI but only covering cognition in the article. Will be interesting to follow this.