Dataset Information

Cerebrospinal fluid markers of neuroinflammation in delirium: a role for interleukin-1? in delirium after hip fracture.

ABSTRACT:

Objective

Exaggerated central nervous system (CNS) inflammatory responses to peripheral stressors may be implicated in delirium. This study hypothesised that the IL-1? family is involved in delirium, predicting increased levels of interleukin-1? (IL-1?) and decreased IL-1 receptor antagonist (IL-1ra) in the cerebrospinal fluid (CSF) of elderly patients with acute hip fracture. We also hypothesised that Glial Fibrillary Acidic Protein (GFAP) and interferon-? (IFN-?) would be increased, and insulin-like growth factor 1 (IGF-1) would be decreased.

Methods

Participants with acute hip fracture aged >60 (N=43) were assessed for delirium before and 3-4 days after surgery. CSF samples were taken at induction of spinal anaesthesia. Enzyme-linked immunosorbent assays (ELISA) were used for protein concentrations.

Results

Prevalent delirium was diagnosed in eight patients and incident delirium in 17 patients. CSF IL-1? was higher in patients with incident delirium compared to never delirium (incident delirium 1.74 pg/ml (1.02-1.74) vs. prevalent 0.84 pg/ml (0.49-1.57) vs. never 0.66 pg/ml (0-1.02), Kruskal-Wallis p=0.03). CSF:serum IL-1? ratios were higher in delirious than non-delirious patients. CSF IL-1ra was higher in prevalent delirium compared to incident delirium (prevalent delirium 70.75 pg/ml (65.63-73.01) vs. incident 31.06 pg/ml (28.12-35.15) vs. never 33.98 pg/ml (28.71-43.28), Kruskal-Wallis p=0.04). GFAP was not increased in delirium. IFN-? and IGF-1 were below the detection limit in CSF.

Conclusion

This study provides novel evidence of CNS inflammation involving the IL-1? family in delirium and suggests a rise in CSF IL-1? early in delirium pathogenesis. Future larger CSF studies should examine the role of CNS inflammation in delirium and its sequelae.

SUBMITTER: Cape E

PROVIDER: S-EPMC4274366 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature

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