Relationships between adiponectin and matrix metalloproteinase-9 (MMP-9) serum levels and postoperative cognitive dysfunction in elderly patients after general anesthesia.

Zaiguo Wang,Xiaoming Hu,Guilan Zhou,Jianer Guo,Dehui Huang,Shu Zhang,Haihui Xie

doi:10.1007/s40520-015-0519-9

Abstract

ObjectiveThe aim of this study was to evaluate the relationships between the serum levels of adiponectin (ADP) and matrix metalloproteinase-9 (MMP-9) and postoperative cognitive dysfunction (POCD) in elderly patients after general anesthesia.MethodsThe cognitive functions of 98 elderly patients who were scheduled to undergo selective hip replacement surgery under general anesthesia were assessed using the Montreal Cognitive Assessment (MoCA) 3 days before surgery and on postoperative Days 1, 2, 3, and 7. The serum levels of ADP and MMP-9 were determined at the same time points, and the presence of POCD on postoperative Day 3 was recorded. The patients were divided into a POCD group and non-POCD group.ResultsPostoperative cognitive dysfunction was observed in 28 patients (28.5 %). Serum MMP-9 levels significantly increased and serum ADP levels significantly decreased in the POCD group at each postoperative time point and in the non-POCD group on postoperative Days 1 and 2 compared to the presurgical levels. Serum MMP-9 levels were significantly higher and serum ADP levels were significantly lower in the POCD group compared with those in the non-POCD group at each time point. In the POCD patients, serum MMP-9 levels were significantly and negatively correlated and serum ADP levels were significantly and positively correlated with the MoCA scores.ConclusionsThe increased serum MMP-9 levels and decreased serum ADP levels in elderly patients after general anesthesia might be involved in the POCD pathophysiological process.

Highlights

Postoperative cognitive dysfunction (POCD), which is a common postoperative complication in elderly patients, delays patient recovery and prolongs their hospitalization
Serum matrix metalloproteinase-9 (MMP-9) levels significantly increased and serum ADP levels significantly decreased in the postoperative cognitive dysfunction (POCD) group at each postoperative time point and in the non-POCD group on postoperative Days 1 and 2 compared to the presurgical levels
Serum MMP-9 levels were significantly higher and serum ADP levels were significantly lower in the POCD group compared with those in the non-POCD group at each time point

Summary

Introduction

Postoperative cognitive dysfunction (POCD), which is a common postoperative complication in elderly patients, delays patient recovery and prolongs their hospitalization. The occurrence of POCD might be related to multiple risk factors, including anesthesia, surgery, and perioperative status, and the mechanisms underlying its occurrence are currently unclear. Adiponectin (ADP), which is a protein hormone that is derived from fat cells and is secreted by fat tissues, has many bioactivities, including anti-inflammation, anti-oxidation, and blood sugar reduction. ADP might have protective effects towards cells, tissues, and organs [1–5], and ADP has been shown to effectively reduce the secretion of central proinflammatory cytokines [6]. The main functions of matrix metalloproteinase-9 (MMP-9), which is a member of a group of Zn2?-dependent proteolytic enzymes, are to degrade and remodel the extracellular matrix. MMP-9 plays a major role in degrading the basal membrane. The abnormal expression of MMP-9 has been directly related to disruption of the blood–brain barrier, and it is a key factor in vasogenic edema and secondary brain injuries.

Methods

Results

Conclusion