Functional imaging reveals cerebral microvascular dysfunction in primary antiphospholipid syndrome: Pathophysiologic...

Area of Science:

• Neuroimmunology
• Vascular Neurology
• Rheumatology

Background:

• Primary antiphospholipid syndrome (PAPS) is an autoimmune disorder causing thrombosis and antiphospholipid antibodies (aPL).
• PAPS is increasingly linked to neuropsychiatric symptoms, often without clear ischemic damage on conventional imaging.
• Subtle cerebral dysfunction may underlie cognitive and mood disturbances in PAPS patients.

Purpose of the Study:

• To investigate cerebral blood flow patterns in well-defined PAPS patients using functional neuroimaging.
• To identify potential subclinical neurovascular abnormalities associated with PAPS.
• To explore the relationship between cerebral hypoperfusion and neuropsychiatric symptoms in PAPS.

Main Methods:

• Brain single-photon emission computed tomography (SPECT) was performed on 25 PAPS patients and age/sex-matched controls.
• Statistical Parametric Mapping (SPM) analysis was used to compare cerebral perfusion between groups.
• Results were analyzed independently of clinical neurological status and MRI findings.

Main Results:

• PAPS patients exhibited significantly reduced cerebral perfusion in bilateral frontoparietal cortices compared to controls.
• This pattern of hypoperfusion was consistent across PAPS patients, irrespective of neurological symptoms or MRI data.
• Findings suggest functional microvascular impairment and neuroinflammation contribute to cerebral dysfunction in PAPS.

Conclusions:

• Functional SPECT imaging reveals subclinical cerebral hypoperfusion in PAPS, indicating microvascular dysfunction beyond thrombosis.
• These findings support a neuroimmunological basis for neuropsychiatric symptoms in PAPS, involving endothelial dysfunction and neuroinflammation.
• Early detection of these functional changes may enable timely therapeutic interventions to prevent neuronal damage.