Background/Aims: The diagnosis of delirium is not supported by specific biomarkers. In a previous study, high neopterin levels were found in patients with a postoperative delirium. In the present study, we investigated levels of neopterin, interleukin-6 (IL-6) and insulin-like growth factor-1 (IGF-1) in acutely ill admitted elderly patients with and without a delirium. Methods: Plasma/serum levels of neopterin, IL-6 and IGF-1 were determined in patients aged ≥65 years admitted to the wards of Internal Medicine and Geriatrics. Differences in biomarker levels between patients with and without a delirium were investigated by the analysis of variance in models adjusted for age, gender, comorbidities and eGFR (when appropriate). Results: Eighty-six patients were included; 23 of them with a delirium. In adjusted models, higher mean levels of neopterin (70.5 vs. 45.9 nmol/l, p = 0.009) and IL-6 (43.1 vs. 18.5 pg/ml, p = 0.034) and lower mean levels of IGF-1 (6.3 vs. 9.3 nmol/l, p = 0.007) were found in patients with a delirium compared to those without. Conclusions: The findings of this study suggest that neopterin might be a potential biomarker for delirium which, through oxidative stress and activation of the immune system, may play a role in the pathophysiology of delirium.

Biomarkers, Delirium, Insulin-like growth factor-1, Interleukin-6, Neopterin
dx.doi.org/10.1159/000366410, hdl.handle.net/1765/85179
Dementia and Geriatric Cognitive Disorders
Department of Immunology

Egberts, A, Wijnbeld, E.H.A, Fekkes, D, van der Ploeg, M.A, Ziere, G, Hooijkaas, H, … Mattace Raso, F.U.S. (2015). Neopterin: A potential biomarker for delirium in elderly patients. Dementia and Geriatric Cognitive Disorders, 39, 116–124. doi:10.1159/000366410