Delirium is a common and serious complication in geriatric patients. The pathophysiology of delirium remains unknown.

The aim of a new study published in the Journal of Alzheimer’s Disease was to test the hypothesis that cerebrospinal fluid (CSF) levels of inflammatory markers at the time of spinal anesthesia for hip surgery are associated with delirium.

This study enrolled 133 hip fracture patients and 125 cognitively healthy controls undergoing elective surgery, together with 73 Alzheimers disease (AD) dementia patients at Oslo University Hospital and Diakonhjemmet Hospital, Oslo, Norway. Delirium was evaluated daily in hip fracture patients by the Confusion Assessment Method (CAM). Depression was evaluated by Cornell Scale for Depression in Dementia (CSDD). Tumor necrosis factor alpha (TNF-α), interleukin-1beta (IL-1β) and interleukin-8 (IL-8) levels were measured in CSF.

The findings revealed that hip fracture patients had significantly higher IL-8 levels compared to cognitively healthy controls or patients with stable AD dementia. Additionally, preoperative IL-8 levels were significantly higher in hip fracture patients who developed delirium (incident delirium) after surgery, as compared to patients with no delirium. On the other hand, subgroup analyses showed that IL-8 levels were only significantly higher in delirium patients without dementia. Meanwhile, the depression subgroup analysis disclosed that IL-8 concentration was significantly higher in delirium patients with depression. Both, TNF-α and IL-1β were undetected in most cases.

Therefore, the results indicated that IL-8 levels are associated with delirium onset, furthermore, underlying depression or dementia influences IL-8 levels.

Source: Journal of Alzheimer’s Disease. 2020 Jan 6. doi: 10.3233/JAD-190941