Poor PASAT performance correlates with MRI contrast enhancement in multiple sclerosis

Area of Science:

• Neuroscience
• Radiology
• Clinical Neurology

Background:

• Cognitive impairment is a significant clinical feature in multiple sclerosis (MS).
• The Paced Auditory Serial Addition Test (PASAT) is a key screening tool for MS-related cognitive dysfunction.
• This study investigates the link between cognitive performance and active inflammatory lesions (gadolinium-enhancing) in MS.

Purpose of the Study:

• To examine the relationship between cognitive function, assessed by PASAT, and the presence of gadolinium-enhancing lesions on MRI in MS patients.
• To determine if active inflammation, indicated by Gd enhancement, affects cognitive performance in stable MS patients.

Main Methods:

• A longitudinal correlational study involving 75 relapsing-remitting MS patients.
• Two MRI scans and clinical assessments (EDSS, MSFC) were performed with a 10-week interval.
• Patients were grouped based on the presence of Gd-enhancing lesions on MRI scans (Gd on 1 scan, both scans, or neither scan).

Main Results:

• PASAT scores were significantly better at time points without gadolinium enhancement (p = 0.002).
• This effect was observed in patients whose first scan showed Gd enhancement.
• No significant changes in MSFC or EDSS were noted between time points in any group, indicating stable physical status.

Conclusions:

• Gadolinium enhancement, a marker of active inflammation, negatively impacts Paced Auditory Serial Addition Test performance in physically stable MS patients.
• This suggests that active inflammatory lesions may cause widespread cerebral connectivity impairment, affecting cognitive function.
• MRI-detected inflammation is a relevant factor influencing cognitive deficits in multiple sclerosis.