Early Cognitive Dysfunction in Elderly Patients after Total Knee Arthroplasty: An Analysis of Risk Factors and Cognitive Functional Levels

Shengjie Ren,Yanan Zhang,Shu Yuan,Bao Lang,Chuanbo Zang,Fang Yuan,Cheng Ni

doi:10.1155/2022/5372603

Abstract

Background Cognitive dysfunction after total knee arthroplasty (TKA) is very common in elderly patients. Postoperative cognitive dysfunction (POCD), as a form of cognitive dysfunction, may affect patients' short- and long-term recoveries. The identification of meaningful risk factors may help reduce the occurrence of POCD in the future. Objective Our goal was to retrospectively investigate the risk factors for early POCD in elderly patients undergoing TKA and to further analyze the relationship between the intensity of risk factors and the level of cognitive function. Methods The related indicators and the Montreal Cognitive Function Assessment Scale (MOCA) scores of 105 elderly patients were collected by searching the electronic case system. According to the postoperative MOCA score, patients were divided into three groups: normal group (group N), mild POCD group (group M), and severe POCD group (group S). SPSS 25.0 software was used for statistical analyses. Results At baseline, the preoperative MOCA score was significantly different in patients with POCD (P ≤ 0.001), while other baseline indicators were not significantly different. In terms of changes in hemoglobin levels, statistically significant differences were observed between group M, group S, and group N (P = 0.039). Among inflammatory indicators, only postoperative CRP levels showed a statistically significant difference in patients with POCD (P = 0.041). Postoperative pain was also significantly different among the three groups (P = 0.009). The multivariate regression analysis revealed that a low preoperative MOCA score and severe postoperative pain were independent risk factors for mild and severe cognitive impairment, while a high postoperative CRP level was only an independent risk factor for mild cognitive impairment. Conclusions Our study found that the level of preoperative cognitive function, postoperative CRP level, and postoperative pain were independent risk factors for POCD. Moreover, the levels of preoperative cognitive function and postoperative pain were more strongly correlated with severe POCD than postoperative CRP levels.

Highlights

With the aging of the population and the improvement of people’s living standards, total knee arthroplasty (TKA) is being increasingly widely implemented in elderly patients
With the exception of the preoperative Montreal Cognitive Function Assessment Scale (MOCA) score, no significant differences in the baseline characteristic data were observed between the three groups, such as sex, age, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), hemoglobin level, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) level, hemameba level, neutrophil counts, American Society of Anesthesiologists (ASA) classification, and comorbidities (Table 1)
No international recommendations or high quality evidence for diagnostics and treatment of neurocognitive impairment that may arise from hypotension-related hypoperfusion is available [16, 17]. Consistent with this result, this study reported the reduction in lowest systolic blood pressure (L-SBP), magnitude of reduction in systolic blood pressure (M-SBP), and M-DBP in patients with severe Postoperative cognitive dysfunction (POCD), but the differences were not statistically significant

Summary

Introduction

With the aging of the population and the improvement of people’s living standards, total knee arthroplasty (TKA) is being increasingly widely implemented in elderly patients It successfully improves quality of life by reducing pain and improving long-term function. Only postoperative CRP levels showed a statistically significant difference in patients with POCD (P = 0:041). The multivariate regression analysis revealed that a low preoperative MOCA score and severe postoperative pain were independent risk factors for mild and severe cognitive impairment, while a high postoperative CRP level was only an independent risk factor for mild cognitive impairment. Our study found that the level of preoperative cognitive function, postoperative CRP level, and postoperative pain were independent risk factors for POCD. The levels of preoperative cognitive function and postoperative pain were more strongly correlated with severe POCD than postoperative CRP levels

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