Biomarkers

Area of Science:

• Neuroscience
• Gerontology
• Inflammation Research

Background:

• Inflammation is implicated in Alzheimer's disease (AD) and other dementias, but its exact role remains unclear.
• Acute systemic inflammation, such as from infection or fracture, can accelerate dementia progression.
• The ASCRIBED study investigated the link between hip fracture, inflammation, and brain injury in dementia.

Purpose of the Study:

• To examine the relationship between acute hip fracture, systemic inflammation, and brain injury biomarkers.
• To compare levels of axonal damage and blood-brain barrier integrity in patients with and without dementia following hip fracture.

Main Methods:

• Recruited participants with dementia and hip fracture, hip fracture without dementia, and a control group with dementia but no acute illness.
• Collected cerebrospinal fluid (CSF) and blood samples to measure inflammatory and brain injury biomarkers.
• Analyzed neurofilament light chain (NFL) as an axonal damage marker and Qalbumin for blood-CSF barrier permeability.

Main Results:

• Hip fracture led to significantly higher neurofilament light chain (NFL) levels, indicating increased axonal injury, particularly in those with co-existing dementia.
• CSF NFL levels were strongly correlated with blood-CSF barrier permeability (Qalbumin), suggesting a link between axonal damage and BBB disruption.
• Patients with dementia and hip fracture exhibited the highest NFL levels compared to other groups.

Conclusions:

• Hip fracture causes significant acute axonal injury, exceeding that seen in stable dementia patients.
• The severity of acute brain injury following hip fracture appears greater in individuals with pre-existing dementia.
• Further research is warranted to understand the mechanisms of this injury and develop therapeutic interventions for brain damage associated with hip fracture in dementia.