Cognitive stimulation during hospitalization improves global cognition of older Taiwanese undergoing elective total knee and hip replacement surgery

Effects of perioperative cognitive function training on postoperative cognitive dysfunction and postoperative delirium: a systematic review and meta-analysis

Background

Randomized controlled trials (RCTs) have shown conflicting results regarding the effects of perioperative cognitive training (CT) on the incidence of postoperative cognitive dysfunction (POCD) and postoperative delirium (POD). We, therefore, performed a meta-analysis to assess the overall effects of studies on this topic.

Methods

We searched PubMed, Embase, the Cochrane Library, and Web of Science for all RCTs and cohort studies that investigated the effects of perioperative CT on the incidence of POCD and POD. Data extraction and quality assessment were conducted independently by two researchers.

Results

This study included nine clinical trials with a total of 975 patients. The results showed that perioperative CT significantly reduced the incidence of POCD compared with the control group [risk ratio (RR) = 0.5, 95% CI (confidence interval): 0.28-0.89, P = 0.02]. Nevertheless, for the incidence of POD, the difference between the two groups was not statistically significant (RR = 0.64; 95% CI: 0.29-1.43, P = 0.28). In addition, the CT group had less postoperative decline in the cognitive function scores compared with the control group [mean differences (MD): 1.58, 95% CI: 0.57-2.59, P = 0.002]. In addition, there were no statistically differences in length of hospital stay between the two groups (MD: -0.18, 95% CI: -0.93-0.57, P = 0.64). Regarding CT adherence, the proportion of patients in the cognitive training group who completed the planned duration of CT was 10% (95% CI: 0.05-0.14, P = 0.258).

Conclusion

Our meta-analysis revealed that perioperative cognitive training is possibly an effective measure to reduce the incidence of POCD, but not for the incidence of POD.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022371306, identifier: CRD42022371306.

Postoperative Delirium and Postoperative Cognitive Dysfunction in Patients with Elective Hip or Knee Arthroplasty: A Narrative Review of the Literature

Postoperative delirium (POD) and postoperative cognitive dysfunction (POCD) are common complications following total knee arthroplasty (TKA) and total hip arthroplasty (THA), affecting the length of hospital stay and increasing medical complications. Although many papers have been published on both conditions in this setting, no reviews have currently been written. Thus, the purpose of our study is to summarize the current literature and provide information about POD and POCD following elective THA or TKA. Our literature search was conducted in the electronic databases PubMed and the Cochrane library. We found that POD is a common complication following elective THA or TKA, with a median incidence of 14.8%. Major risk factors include older age, cognitive impairment, dementia, preoperative (pre-op) comorbidities, substance abuse, and surgery for fracture. Diagnosis can be achieved using tools such as the confusion assessment method (CAM), which is sensitive, specific, reliable, and easy to use, for the identification of POD. Treatment consists of risk stratification and the implementation of a multiple component prevention protocol. POCD has a median incidence of 19.3% at 1 week, and 10% at 3 months. Risk factors include older age, high BMI, and cognitive impairment. Treatment consists of reversing risk factors and implementing protocols in order to preserve physiological stability. POD and POCD are common and preventable complications following TKA and THA. Risk stratification and specific interventions can lower the incidence of both syndromes. Every physician involved in the care of such patients should be informed on every aspect of these conditions in order to provide the best care for their patients.

Sleep, Pain, and Cognition: Modifiable Targets for Optimal Perioperative Brain Health

The prevention of perioperative neurocognitive disorders is a priority for patients, families, clinicians, and researchers. Given the multiple risk factors present throughout the perioperative period, a multicomponent preventative approach may be most effective. The objectives of this narrative review are to highlight the importance of sleep, pain, and cognition on the risk of perioperative neurocognitive disorders and to discuss the evidence behind interventions targeting these modifiable risk factors. Sleep disruption is associated with postoperative delirium, but the benefit of sleep-related interventions is uncertain. Pain is a risk factor for postoperative delirium, but its impact on other postoperative neurocognitive disorders is unknown. Multimodal analgesia and opioid avoidance are emerging as best practices, but data supporting their efficacy to prevent delirium are limited. Poor preoperative cognitive function is a strong predictor of postoperative neurocognitive disorder, and work is ongoing to determine whether it can be modified to prevent perioperative neurocognitive disorders.

Conversion between Mini-Mental State Examination and Montreal Cognitive Assessment scores in older adults undergoing selective surgery using Rasch analysis

AIMS

To develop and validate a conversion table between the MMSE and the MoCA using Rasch analysis in older adults undergoing selective surgery and examine its diagnostic accuracy in detecting cognitive impairment.

DESIGN

Cross-sectional study.

METHODS

Older patients [N = 129; age 66.0 (4.6) years, education 7.7 (3.5) years] undergoing elective surgery were recruited from December 2017 to June 2018. All participants completed the MMSE and MoCA and 113 of them completed a battery of neuropsychological tests. Common person linking based on Rasch analysis was performed to develop the conversion table. The conversions were validated by calculating the intraclass correlation coefficient (ICC), score differences between actual and converted scores, and root mean squared error of the difference (RMSE). The diagnostic accuracy of the conversions for detecting cognitive impairment was also tested.

RESULTS

The MoCA [person measure: 1.3 (1.1) logits] was better targeted to the patients than the MMSE [person measure: 3.2 (1.3) logits]. Conversion from MoCA to MMSE scores (ICC 0.84, 95% CI 0.77-0.88; RMSE 1.36) was more precise than conversion from MMSE to MoCA (ICC 0.82, 95% CI 0.75-0.87; RMSE 2.56). Conversion from MoCA to MMSE demonstrated better diagnostic accuracy in detecting cognitive impairment than the actual MMSE, whereas conversion from MMSE to MoCA exhibited the opposite pattern.

CONCLUSION

Conversion from MoCA to MMSE was more precise and had better diagnostic accuracy in detecting pre-operative cognitive impairment in older patients undergoing selective surgery than conversion from MMSE into MoCA.

IMPACT

The finding is useful for interpreting, comparing, and integrating cognitive measurements in surgical settings and clinical research. Statistically sound conversion between MoCA and MMSE based on Rasch analysis is now possible for surgical setting and clinical research.

Working Memory Training for Older Adults After Major Surgery: Benefits to Cognitive and Emotional Functioning

OBJECTIVES

Cognitive and mood changes can affect postoperative recovery in hospitalized older adults undergoing major surgical procedures, but few studies have considered postoperative cognitive interventions to sustain such patients' cognitive functioning and mood. The aim of this pilot study was to assess the efficacy of working memory training in improving cognitive functioning and mood, or emotional functioning, in older adults undergoing major surgery.

METHODS

Thirty-four older adults (from 64 to 75 years of age) hospitalized for partial or total arthroplasty of the knee were randomly assigned to either a trained group (N = 18) or an active control group (N = 16). The former received working memory training during the postoperative period, while the latter engaged in alternative activities. In addition to specific training gains in a working memory task similar to the one used in the training (criterion task), transfer effects to cognitive abilities (short- and long-term memory, and cognitive inhibition), and mood or emotional functioning (signs of depression or anxiety) were investigated.

RESULTS

Immediately after the training, results showed a main effect of group (in favor of the trained group) in the criterion task, in one of the short-term memory measures, and in cognitive inhibition. In addition, only the trained group showed a decrease in depression and anxiety scores.

CONCLUSION

The results of this pilot study suggest that cognitive training targeting working memory administered in the postoperative period after major surgery can sustain older adults' cognitive and emotional functioning, and especially their mood.

Older Adults With Hip Arthroplasty: An Individualized Transitional Care Program

BACKGROUND

Most older adults with hip fracture surgery experience functional decline (FD), causing devastating outcomes. However, few studies have examined the effects of nursing interventions to reduce FD for them.

PURPOSE

The aim of the study was to evaluate an individualized transitional care program (ITCP) to reduce FD for older adults with hip arthroplasty.

METHODS

The study was quasiexperimental, with a nonequivalent control group design. A total of 37 participants scheduled for hip arthroplasty were recruited-21 in the experimental and 16 in the control group.

FINDINGS

Two weeks following surgery (i.e., just prior to discharge), the ITCP group displayed less fear of falling than the usual care group. Moreover, the experimental group displayed objectively less FD with increased activities of daily living and Timed Up and Go scores, 6 weeks after hip arthroplasty.

CONCLUSIONS

This study provides evidence of the effectiveness of nurse-led rehabilitative practices to reduce FD in older adults with hip arthroplasty.

CLINICAL RELEVANCE

The ITCP promoted individual physical functioning for older adults with hip arthroplasty. This study results can aid healthy transitions of elderly patients with other various diseases.

Effect of a Modified Hospital Elder Life Program on Delirium and Length of Hospital Stay in Patients Undergoing Abdominal Surgery: A Cluster Randomized Clinical Trial

Importance

Older patients undergoing abdominal surgery commonly experience preventable delirium, which extends their hospital length of stay (LOS).

Objective

To examine whether a modified Hospital Elder Life Program (mHELP) reduces incident delirium and LOS in older patients undergoing abdominal surgery.

Design, Setting, and Participants

This cluster randomized clinical trial of 577 eligible patients enrolled 377 older patients (≥65 years of age) undergoing gastrectomy, pancreaticoduodenectomy, and colectomy at a 2000-bed urban medical center in Taipei, Taiwan, from August 1, 2009, through October 31, 2012. Consecutive older patients scheduled for elective abdominal surgery with expected LOS longer than 6 days were enrolled, with a recruitment rate of 65.3%. Participants were cluster randomized by room to receive the mHELP or usual care.

Interventions

The intervention (implemented by an mHELP nurse) consisted of 3 protocols administered daily: orienting communication, oral and nutritional assistance, and early mobilization. Intervention group participants received all 3 mHELP protocols postoperatively, in addition to usual care, as soon as they arrived in the inpatient ward and until hospital discharge. Adherence to protocols was tracked daily.

Main Outcomes and Measures

Presence of delirium was assessed daily by 2 trained nurses who were masked to intervention status by using the Confusion Assessment Method. Data on LOS were abstracted from the medical record.

Results

Of 577 eligible patients, 377 (65.3%) were enrolled and randomly assigned to the mHELP (n = 197; mean [SD] age, 74.3 [5.8] years; 111 [56.4%] male) or control (n = 180; mean [SD] age, 74.8 [6.0] years; 103 [57.2%] male) group. Postoperative delirium occurred in 13 of 196 (6.6%) mHELP participants vs 27 of 179 (15.1%) control individuals, representing a relative risk of 0.44 in the mHELP group (95% CI, 0.23-0.83; P = .008). Intervention group participants received the mHELP for a median of 7 days (interquartile range, 6-10 days) and had a shorter median LOS (12.0 days) than control participants (14.0 days) (P = .04).

Conclusions and Relevance

For older patients undergoing abdominal surgery who received the mHELP, the odds of delirium were reduced by 56% and LOS was reduced by 2 days. Our findings support using the mHELP to advance postoperative care for older patients undergoing major abdominal surgery.

Trial Registration

clinicaltrials.gov Identifier: NCT01045330.

From gut dysbiosis to altered brain function and mental illness: mechanisms and pathways

The human body hosts an enormous abundance and diversity of microbes, which perform a range of essential and beneficial functions. Our appreciation of the importance of these microbial communities to many aspects of human physiology has grown dramatically in recent years. We know, for example, that animals raised in a germ-free environment exhibit substantially altered immune and metabolic function, while the disruption of commensal microbiota in humans is associated with the development of a growing number of diseases. Evidence is now emerging that, through interactions with the gut-brain axis, the bidirectional communication system between the central nervous system and the gastrointestinal tract, the gut microbiome can also influence neural development, cognition and behaviour, with recent evidence that changes in behaviour alter gut microbiota composition, while modifications of the microbiome can induce depressive-like behaviours. Although an association between enteropathy and certain psychiatric conditions has long been recognized, it now appears that gut microbes represent direct mediators of psychopathology. Here, we examine roles of gut microbiome in shaping brain development and neurological function, and the mechanisms by which it can contribute to mental illness. Further, we discuss how the insight provided by this new and exciting field of research can inform care and provide a basis for the design of novel, microbiota-targeted, therapies.

Cognitive Impairment in Hospitalized Seniors

Cognitive disorders are highly prevalent in hospitalized seniors, and can be due to delirium, dementia, as well as other disorders. Hospitalization can have adverse cognitive effects, and cognitive dysfunction adversely affects hospital outcomes. In this article, the literature is reviewed on how hospitalization affects cognitive function and how cognitive impairment affects hospital outcomes. Possible interventions in cognitively impaired hospitalized seniors are reviewed.

Cognitive stimulation of the default-mode network modulates functional connectivity in healthy aging

A cognitive-stimulation tool was created to regulate functional connectivity within the brain Default-Mode Network (DMN). Computerized exercises were designed based on the hypothesis that repeated task-dependent coactivation of multiple DMN regions would translate into regulation of resting-state network connectivity. Forty seniors (mean age: 65.90 years; SD: 8.53) were recruited and assigned either to an experimental group (n=21) who received one month of intensive cognitive stimulation, or to a control group (n=19) who maintained a regime of daily-life activities explicitly focused on social interactions. An MRI protocol and a battery of neuropsychological tests were administered at baseline and at the end of the study. Changes in the DMN (measured via functional connectivity of posterior-cingulate seeds), in brain volumes, and in cognitive performance were measured with mixed models assessing group-by-timepoint interactions. Moreover, regression models were run to test gray-matter correlates of the various stimulation tasks. Significant associations were found between task performance and gray-matter volume of multiple DMN core regions. Training-dependent up-regulation of functional connectivity was found in the posterior DMN component. This interaction was driven by a pattern of increased connectivity in the training group, while little or no up-regulation was seen in the control group. Minimal changes in brain volumes were found, but there was no change in cognitive performance. The training-dependent regulation of functional connectivity within the posterior DMN component suggests that this stimulation program might exert a beneficial impact in the prevention and treatment of early AD neurodegeneration, in which this neurofunctional pathway is progressively affected by the disease.

Feasibility and safety of early combined cognitive and physical therapy for critically ill medical and surgical patients: the Activity and Cognitive Therapy in ICU (ACT-ICU) trial

PURPOSE

Cognitive impairment after critical illness is common and debilitating. We developed a cognitive therapy program for critically ill patients and assessed the feasibility and safety of administering combined cognitive and physical therapy early during a critical illness.

METHODS

We randomized 87 medical and surgical ICU patients with respiratory failure and/or shock in a 1:1:2 manner to three groups: usual care, early once-daily physical therapy, or early once-daily physical therapy plus a novel, progressive, twice-daily cognitive therapy protocol. Cognitive therapy included orientation, memory, attention, and problem-solving exercises, and other activities. We assessed feasibility outcomes of the early cognitive plus physical therapy intervention. At 3 months, we also assessed cognitive, functional, and health-related quality of life outcomes. Data are presented as median (interquartile range) or frequency (%).

RESULTS

Early cognitive therapy was a delivered to 41/43 (95%) of cognitive plus physical therapy patients on 100% (92-100%) of study days beginning 1.0 (1.0-1.0) day following enrollment. Physical therapy was received by 17/22 (77%) of usual care patients, by 21/22 (95%) of physical therapy only patients, and 42/43 (98%) of cognitive plus physical therapy patients on 17% (10-26%), 67% (46-87%), and 75% (59-88%) of study days, respectively. Cognitive, functional, and health-related quality of life outcomes did not differ between groups at 3-month follow-up.

CONCLUSIONS

This pilot study demonstrates that early rehabilitation can be extended beyond physical therapy to include cognitive therapy. Future work to determine optimal patient selection, intensity of treatment, and benefits of cognitive therapy in the critically ill is needed.

Postoperative cognitive dysfunction after total joint arthroplasty in the elderly: a meta-analysis

This meta-analysis consolidated the research on postoperative cognitive dysfunction (POCD) following total joint arthroplasty (TJA). Data from 17 studies that assessed cognition pre- and post-surgery in TJA patients alone (15 studies) or matched TJA and control groups (2 studies) were analysed. Results were grouped by cognitive domain (memory, attention, language, speed, general cognition) and follow-up interval (pre-discharge, 3-6 months post-surgery). The TJA data revealed small declines in reaction time and general cognition pre-discharge, but no evidence of decline 3-6 months post-surgery. Very limited TJA and Control data indicated no group differences in the changes to performance over time; however, the TJA group was cognitively compromised pre- and post-surgery compared to Controls. Further appropriately controlled research is required to clarify whether POCD commonly occurs after TJA.

The modified Hospital Elder Life Program: adapting a complex intervention for feasibility and scalability in a surgical setting

The purpose of this article is to provide the rationale and methods for adapting the Hospital Elder Life Program (HELP). The HELP is a complex intervention that has been shown to reduce rates of delirium and functional decline. However, modification of the program may be required to meet local circumstances and specialized populations. We selected three key elements based on our prior work and the concept of shared risk factors and modified the HELP to include only three shared risk factors (functional, nutritional, and cognitive status) that were targeted by three nursing protocols: early mobilization, oral and nutritional assistance, and orienting communication. These protocols were adapted, refined, and pilot-tested for feasibility and efficacy. We hope by reporting the rationale and protocols for the modified HELP, we will advance the field for others adapting evidence-based, complex nursing interventions.

Randomized clinical trial of yoga-based intervention in residents from elderly homes: Effects on cognitive function

CONTEXT

Elderly have increased risk for cognitive impairment and dementia. Yoga therapy may be helpful in elderly to improve cognitive function.

AIMS

We examined the benefits of yoga-based intervention compared with waitlist control group on cognitive function in the residents of elderly homes.

SETTINGS AND DESIGN

Single blind controlled study with block randomization of elderly homes.

MATERIALS AND METHODS

Study sample included yoga group (n=62) and waitlist group (n=58). A total of 87 subjects (yoga=44, waitlist=43) completed the study period of 6 months. Yoga group received daily yoga sessions for 1 month, weekly until 3(rd) month and encouraged to continue unsupervised until 6 months. They were assessed on Rey's Auditory Verbal Learning Test (RAVLT), Rey's complex figure test (CFT), Wechsler's Memory Scale (WMS)-digit and spatial span, Controlled Oral Word Association (COWA) test, Stroop Color Word Interference Test and Trail Making Test A and B at baseline and at the end of 6(th) month.

STATISTICAL ANALYSIS

Paired t-test and analysis of covariance (ANCOVA) to compare the difference in neuropsychological test scores.

RESULTS

Yoga group showed significant improvement in immediate and delayed recall of verbal (RAVLT) and visual memory (CFT), attention and working memory (WMS-spatial span), verbal fluency (COWA), executive function (Stroop interference) and processing speed (Trail Making Test-A) than waitlist group at the end of 6 months after correcting for corresponding baseline score and education.

CONCLUSION

Yoga based-intervention appears beneficial to improve several domains of cognitive function in elderly living in residential care homes. Study findings need to be interpreted after considering methodological limitations like lack of active comparison group.