Effects of sepsis on hippocampal volume and memory function

Area of Science:

• Neuroscience
• Critical Care Medicine
• Neurology

Background:

• Sepsis can affect brain integrity, memory, and executive function.
• Sepsis-associated encephalopathy (SAE) is a known complication.
• The impact of sepsis on brain function in patients without SAE but with abnormal EEGs is less understood.

Purpose of the Study:

• To determine the effects of sepsis on brain integrity, memory, and executive function in patients without SAE but with abnormal EEGs.
• To investigate hippocampal volume changes in sepsis patients.
• To correlate brain changes with cognitive deficits.

Main Methods:

• Included 20 sepsis patients with abnormal EEGs (no SAE) and 20 healthy controls.
• Utilized neuropsychological tests (e.g., CVLT-II) for memory and executive function.
• Performed brain MRI with FreeSurfer for hippocampal volume measurement; used APACHE II score for disease severity.

Main Results:

• Sepsis patients exhibited lower scores in verbal learning, recall, and explicit memory.
• Significantly reduced left and right hippocampal volumes were observed in sepsis patients.
• Hippocampal volume correlated negatively with disease severity (APACHE II) and positively with memory recall.

Conclusions:

• Sepsis, even without SAE, leads to reduced hippocampal volume and memory deficits.
• Specific damage occurs in the hippocampus, affecting recollection.
• Abnormal EEGs in sepsis patients indicate underlying brain injury impacting cognitive function.