Brain Amyloid-β Peptide Is Associated with Pain Intensity and Cognitive Dysfunction in Osteoarthritic Patients

Area of Science:

• Neuroscience
• Immunology
• Gerontology

Background:

• Osteoarthritis (OA) is a known risk factor for dementia.
• The underlying mechanisms linking OA to cognitive dysfunction are not fully understood.
• Inflammation and Alzheimer's disease (AD) biomarkers are implicated in cognitive decline.

Purpose of the Study:

• To investigate the associations between pro-inflammatory cytokines, AD biomarkers, pain intensity, and cognitive decline in knee OA patients.
• To explore the role of specific biomarkers in the OA-cognitive dysfunction relationship.

Main Methods:

• Prospective, observational study of 50 patients (26 OA, 24 controls).
• Assessed pain intensity (Visual Analogue Scale - VAS) and cognitive function (Cognitive Abilities Screening Instrument - CASI).
• Measured plasma and cerebrospinal fluid (CSF) levels of inflammatory molecules and AD biomarkers (Aβ40, Aβ42, tau) using multiplex immunoassay.

Main Results:

• OA patients showed poorer cognitive performance compared to controls.
• Higher VAS pain scores correlated negatively with CASI scores across multiple cognitive domains.
• In OA patients, VAS scores correlated positively with CSF fractalkine, Aβ40, and Aβ42.
• CSF Aβ40 and Aβ42 levels negatively correlated with attention and abstract thinking scores.

Conclusions:

• Knee OA is associated with impaired cognitive performance, particularly in patients experiencing chronic pain.
• Elevated levels of AD biomarkers (Aβ40, Aβ42) in CSF may partially mediate the relationship between OA, pain, and cognitive decline.
• Findings highlight the potential role of neuroinflammation and AD pathology in OA-related cognitive impairment.