Role of CRP, TNF-a, and IGF-1 in Delirium Pathophysiology

Delirium is a common and life-threatening neuropsychiatric syndrome. Diagnosing delirium can be challenging, which increases mortality and mortality rates and health care costs. The biologic model of delirium is not definite yet, but evidence supports a cholinergic deficiency model. Delirium may be the result of processes and drugs that trespass a compromised blood-brain barrier. We aimed to evaluate the possible diagnostic utilization and the role of certain biomarkers, such as C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), and insulin like growth factor-1 (IGF-1), in delirium etiology.

A total of 93 inpatients that planned to undergo cardiovascular surgery were informed; 35 of them completed the study. Medical history and current cognitive status were evaluated pre-operatively. Participants were followed using Delirium Rating Scale-Revised-98 Turkish (DRS-R98-T) for delirium symptoms, and blood samples were collected post-operatively.

Delirium was developed more in participants who had worse pre-operative cognitive status. Also, low pre-operative IGF-1 levels were detected in the delirium group. Pre-operative CRP and TNF-α levels were not different between groups.

Low IGF-1 levels can be used to predict delirium after surgery. However, the complex nature of cytokines and delirium itself make it difficult to utilize cytokines to predict delirium instead of psychometric tools.