TY - JOUR
T1 - Consistent patterns in the inconsistent associations of Insulin-like growth factor 1 (IGF-1), C-Reactive Protein (C-RP) and Interleukin 6 (IL-6) levels with delirium in surgical populations. A systematic review and meta-analysis
AU - Adamis, Dimitrios
AU - van Gool, Willem A.
AU - Eikelenboom, Piet
N1 - Funding Information: We would like to thank Prof S. Vasunilashorn and her colleagues for providing data for this meta-analysis. Publisher Copyright: © 2021 Copyright: Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2021/11/1
Y1 - 2021/11/1
N2 - Background: Biomarkers for delirium could increase diagnostic accuracy and may help to identify pathological pathways. Until now study findings concerning cytokine levels have been inconsistent. Aims: Systematic review and meta-analysis investigating the association between peripheral levels of Insulin-like Growth Factor-1 (IGF-1), C-Reactive Protein (C-RP) and Interleukin-6 (IL-6) and delirium in surgical patients, and to explore if there are distinct/specific patterns that may potentially explain inconsistent results. Methods: PubMed, Scopus, CINAHL, Cochrane, and EMBASE databases were searched. Inclusion criteria were: prospective studies, surgical populations excluding preoperative delirium, available data. The following were collected: type of operation (orthopaedic, abdominal, etc), the timing of operation (acute, elective, both), demographics, number of participants with delirium, time of preoperative blood withdrawal, and preoperative levels of each biomarker. Results: Low levels of IGF-1 (n = 7 studies) are significantly associated with post-operative delirium in abdominal surgical samples. High levels of C-RP (n = 9) are associated with delirium in acute orthopaedic and elective abdominal operations. IL-6 (n = 14) is a significant predictor of post-operative delirium in a variety of surgical conditions (elective or acute). Discussion: A common pattern exists in the otherwise conflicting reported findings. This similarity may reflect different underling mechanisms and predisposing factors like cachexia and catabolic stages. It seems that delirium in abdominal surgery is triggered by IGF-1 disturbances, while in other surgeries by an inflammatory reaction. Conclusions: Despite the contradictory results concerning the association of IGF-1, C-RP and IL-6 with postoperative delirium, the present meta-analysis shows that there are certain patterns. IL-6 seems a consistent predictor for delirium in surgical samples.
AB - Background: Biomarkers for delirium could increase diagnostic accuracy and may help to identify pathological pathways. Until now study findings concerning cytokine levels have been inconsistent. Aims: Systematic review and meta-analysis investigating the association between peripheral levels of Insulin-like Growth Factor-1 (IGF-1), C-Reactive Protein (C-RP) and Interleukin-6 (IL-6) and delirium in surgical patients, and to explore if there are distinct/specific patterns that may potentially explain inconsistent results. Methods: PubMed, Scopus, CINAHL, Cochrane, and EMBASE databases were searched. Inclusion criteria were: prospective studies, surgical populations excluding preoperative delirium, available data. The following were collected: type of operation (orthopaedic, abdominal, etc), the timing of operation (acute, elective, both), demographics, number of participants with delirium, time of preoperative blood withdrawal, and preoperative levels of each biomarker. Results: Low levels of IGF-1 (n = 7 studies) are significantly associated with post-operative delirium in abdominal surgical samples. High levels of C-RP (n = 9) are associated with delirium in acute orthopaedic and elective abdominal operations. IL-6 (n = 14) is a significant predictor of post-operative delirium in a variety of surgical conditions (elective or acute). Discussion: A common pattern exists in the otherwise conflicting reported findings. This similarity may reflect different underling mechanisms and predisposing factors like cachexia and catabolic stages. It seems that delirium in abdominal surgery is triggered by IGF-1 disturbances, while in other surgeries by an inflammatory reaction. Conclusions: Despite the contradictory results concerning the association of IGF-1, C-RP and IL-6 with postoperative delirium, the present meta-analysis shows that there are certain patterns. IL-6 seems a consistent predictor for delirium in surgical samples.
KW - Biomarkers
KW - C-Reactive Protein (C-RP)
KW - Delirium
KW - Insulin-like Growth Factor 1 (IGF-1)
KW - Interleukin 6 (IL-6)
KW - Meta-analysis
KW - Pathophysiology
UR - http://www.scopus.com/inward/record.url?scp=85114921479&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/j.archger.2021.104518
DO - https://doi.org/10.1016/j.archger.2021.104518
M3 - Review article
C2 - 34536657
SN - 0167-4943
VL - 97
JO - Archives of gerontology and geriatrics
JF - Archives of gerontology and geriatrics
M1 - 104518
ER -