The Use of MoCA and Other Cognitive Tests in Evaluation of Cognitive Impairment in Elderly Patients Undergoing Arthroplasty

Factors affecting short-term functional gain following total knee arthroplasty in patients aged from 75 years at a postacute rehabilitation setting

The intensive rehabilitation of older patients after total knee arthroplasty (TKA) is vital for short-term improvement in mobility and daily living activities. We aimed to investigate the effectiveness of multidisciplinary rehabilitation and assess the early postoperative predictors that are associated with functional gain in TKA patients aged from 75 years in a postacute care setting. This study included 190 patients following primary TKA who were admitted at the postacute rehabilitation hospital. The main outcome measures were the motor component of functional independence measure (M-FIM), M-FIM effectiveness, numerical rating scale, knee extension strength and range of motion, 10-m walk test, Berg balance scale (BBS), and mini-mental state examination (MMSE). The functional gain between patient age groups of ≥75 (n = 105) and <75 (n = 85) years were compared. Although patients aged ≥75 years showed lower improvement in BBS score compared with <75 years, the M-FIM gains and other physical functions were similar in both age groups. In multivariate analysis, the results for M-FIM at admission (β: -0.703; P = 0.001), BBS (β: 0.342; P = 0.032) and MMSE (β: 0.446; P = 0.021) were independently associated with functional gain in the patients following TKA aged ≥75 years. Multidisciplinary inpatient rehabilitation was beneficial for basic functional gain except for improvement in balance ability in patients after TKA aged ≥75 years. Functional level, balance ability and cognitive status in the early postoperative period can be useful predictors for short-term functional gain in the postacute care phase.

Screening for Mild Cognitive Impairment in the Preoperative Setting: A Narrative Review

Cognitive impairment predisposes patients to the development of delirium and postoperative cognitive dysfunction. In particular, in older patients, the adverse sequelae of cognitive decline in the perioperative period may contribute to adverse outcomes after surgical procedures. Subtle signs of cognitive impairment are often not previously diagnosed. Therefore, the aim of this review is to describe the available cognitive screeners suitable for preoperative screening and their psychometric properties for identifying mild cognitive impairment, as preoperative workup may improve perioperative care for patients at risk for postoperative cognitive dysfunction. Electronic systematic and snowball searches of PubMed, PsycInfo, ClinicalKey, and ScienceDirect were conducted for the period 2015–2020. Major inclusion criteria for articles included those that discussed a screener that included the cognitive domain ‘memory’, that had a duration time of less than 15 min, and that reported sensitivity and specificity to detect mild cognitive impairment. Studies about informant-based screeners were excluded. We provided an overview of the characteristics of the cognitive screener, such as interrater and test-retest reliability correlations, sensitivity and specificity for mild cognitive impairment and cognitive impairment, and duration of the screener and cutoff points. Of the 4775 identified titles, 3222 were excluded from further analysis because they were published prior to 2015. One thousand four hundred and forty-eight titles did not fulfill the inclusion criteria. All abstracts of 52 studies on 45 screeners were examined of which 10 met the inclusion criteria. For these 10 screeners, a further snowball search was performed to obtain related studies, resulting in 20 articles. Screeners included in this review were the Mini-Cog, MoCA, O3DY, AD8, SAGE, SLUMS, TICS(-M), QMCI, MMSE2, and Mini-ACE. The sensitivity and specificity range to detect MCI in an older population is the highest for the MoCA, with a sensitivity range of 81–93% and a specificity range of 74–89%. The MoCA, with the highest combination of sensitivity and specificity, is a feasible and valid routine screening of pre-surgical cognitive function. This warrants further implementation and validation studies in surgical pathways with a large proportion of older patients.

Post-Operative Cognitive Impairment: A Cognitive Epidemiology Perspective

Cognitive epidemiology investigates cognitive predictors of health and disease outcomes. Post-operative cognitive impairment is a common complication of surgery but has been neglected as a health outcome in cognitive epidemiology research. This is despite the fact that knowledge of cognitive predictors of post-operative cognitive impairment can be utilized for risk stratification, informed decision-making (in elective surgery), and personalized care of patients during the postoperative period. In this narrative review, the current literature on cognitive predictors of post-operative cognitive impairment and gaps therein are summarized.

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.

Developing guidelines for the translation and cultural adaptation of the Montreal Cognitive Assessment: scoping review and qualitative synthesis

BACKGROUND

Ethnic minorities in countries such as the UK are at increased risk of dementia or minor cognitive impairment. Despite this, cognitive tests used to provide a timely diagnosis for these conditions demonstrate performance bias in these groups, because of cultural context. They require adaptation that accounts for language and culture beyond translation. The Montreal Cognitive Assessment (MoCA) is one such test that has been adapted for multiple cultures.

AIMS

We followed previously used methodology for culturally adapting cognitive tests to develop guidelines for translating and culturally adapting the MoCA.

METHOD

We conducted a scoping review of publications on different versions of the MoCA. We extracted their translation and cultural adaptation procedures. We also distributed questionnaires to adaptors of the MoCA for data on the procedures they undertook to culturally adapt their respective versions.

RESULTS

Our scoping review found 52 publications and highlighted seven steps for translating the MoCA. We received 17 responses from adaptors on their cultural adaptation procedures, with rationale justifying them. We combined data from the scoping review and the adaptors' feedback to form the guidelines that state how each question of the MoCA has been previously adapted for different cultural contexts and the reasoning behind it.

CONCLUSIONS

This paper details our development of cultural adaptation guidelines for the MoCA that future adaptors can use to adapt the MoCA for their own languages or cultures. It also replicates methods previously used and demonstrates how these methods can be used for the cultural adaptation of other cognitive tests.

Mini-Cog for the detection of dementia within a primary care setting

BACKGROUND

Alzheimer's disease and other forms of dementia are becoming increasingly common with the aging of most populations. The majority of individuals with dementia will first present for care and assessment in primary care settings. There is a need for brief dementia screening instruments that can accurately detect dementia in primary care settings. The Mini-Cog is a brief, cognitive screening test that is frequently used to evaluate cognition in older adults in various settings.

OBJECTIVES

To determine the accuracy of the Mini-Cog for detecting dementia in a primary care setting.

SEARCH METHODS

We searched the Cochrane Dementia and Cognitive Improvement Register of Diagnostic Test Accuracy Studies, MEDLINE, Embase and four other databases, initially to September 2012. Since then, four updates to the search were performed using the same search methods, and the most recent was January 2017. We used citation tracking (using the databases' 'related articles' feature, where available) as an additional search method and contacted authors of eligible studies for unpublished data.

SELECTION CRITERIA

We only included studies that evaluated the Mini-Cog as an index test for the diagnosis of Alzheimer's disease dementia or related forms of dementia when compared to a reference standard using validated criteria for dementia. We only included studies that were conducted in primary care populations.

DATA COLLECTION AND ANALYSIS

We extracted and described information on the characteristics of the study participants and study setting. Using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) criteria we evaluated the quality of studies, and we assessed risk of bias and applicability of each study for each domain in QUADAS-2. Two review authors independently extracted information on the true positives, true negatives, false positives, and false negatives and entered the data into Review Manager 5 (RevMan 5). We then used RevMan 5 to determine the sensitivity, specificity, and 95% confidence intervals. We summarized the sensitivity and specificity of the Mini-Cog in the individual studies in forest plots and also plotted them in a receiver operating characteristic plot. We also created a 'Risk of bias' and applicability concerns graph to summarize information related to the quality of included studies.

MAIN RESULTS

There were a total of four studies that met our inclusion criteria, including a total of 1517 total participants. The sensitivity of the Mini-Cog varied between 0.76 to 1.00 in studies while the specificity varied between 0.27 to 0.85. The included studies displayed significant heterogeneity in both methodologies and clinical populations, which did not allow for a meta-analysis to be completed. Only one study (Holsinger 2012) was found to be at low risk of bias on all methodological domains. The results of this study reported that the sensitivity of the Mini-Cog was 0.76 and the specificity was 0.73. We found the quality of all other included studies to be low due to a high risk of bias with methodological limitations primarily in their selection of participants.

AUTHORS' CONCLUSIONS

There is a limited number of studies evaluating the accuracy of the Mini-Cog for the diagnosis of dementia in primary care settings. Given the small number of studies, the wide range in estimates of the accuracy of the Mini-Cog, and methodological limitations identified in most of the studies, at the present time there is insufficient evidence to recommend that the Mini-Cog be used as a screening test for dementia in primary care. Further studies are required to determine the accuracy of Mini-Cog in primary care and whether this tool has sufficient diagnostic test accuracy to be useful as a screening test in this setting.

Preoperative Cognitive Impairment as a Perioperative Risk Factor in Patients Undergoing Total Knee Arthroplasty

Background:

The study assessed whether pre-existing cognitive impairment (CI) prior to elective total knee arthroplasty (TKA) is associated with worse postoperative outcomes such as delirium, in-hospital medical complications, 30-day mortality, hospital length of stay and non-home discharge.

Methods:

A retrospective database analysis from the NSQIP Geriatric Surgery Pilot Project was used. There was an initial cohort of 6350 patients undergoing elective TKA, 104 patients with CI were propensity score matched to 104 patients without CI.

Results:

Analysis demonstrated a significantly increased incidence of post-operative delirium (POD) in the cohort with pre-op CI (p = < .001), a worsened functional status (p = < .001) and increased nonhome discharge postoperatively compared to the group without CI (p = 0.029). Other post-operative outcomes included 30-day mortality of 0% in both groups, and low rate of complications such as infection (2.88% vs 0.96%), pneumonia (1.92% vs 0%), failure to wean (0.96% vs 0%), and reintubation (0.96% vs 0%). Some other differences between the CI group and non-CI group, although not statistically significant, included increased rate of transfusion (10.58% vs 6.73%), and sepsis (1.92% vs 0%). The length of stay was increased in the non-CI group (4.28% vs 2.32%, p = 0.122).

Conclusion:

CI in patients undergoing TKA is associated with an increased risk of POD, worsened postoperative functional status, and discharge to non-home facility.

Analysis of early failure rate and its risk factor with 2157 total ankle replacements

The failure rate of TAA is still higher than that of other joint replacement procedures. This study aimed to calculate the early failure rate and identify associated patient factors. Data from the Korean Health Insurance Review and Assessment Service database from 2009 to 2017 were collected. We evaluated patients who had TAA as a primary surgical procedure. Early failure was defined as conversion to revision TAA or arthrodesis after primary TAA within five years. Patients with early failure after primary TAA were designated as the "Failure group". Patients without early failure and who were followed up unremarkably for at least five years after primary TAA were designated as the "No failure group". Overall, 2157 TAA participants were included. During the study period, 197 patients developed failure within five years postoperatively, for an overall failure rate of 9.1%. Significant risk factors for early failure were history of chronic pulmonary disease, diabetes, peripheral vascular disease, hyperlipidemia, dementia, and alcohol abuse. A significant increase of odds ratio was found in patients with a history of dementia, chronic pulmonary disease, and diabetes. Surgical indications and preoperative patient counseling should consider these factors.

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.

Cognitive impairment assessment and interventions to optimize surgical patient outcomes

For elderly patients undergoing elective surgical procedures, preoperative evaluation of cognition is often overlooked. Patients may experience postoperative delirium (POD) and postoperative cognitive decline (POCD), especially those with certain risk factors, including advanced age. Preoperative cognitive impairment is a leading risk factor for both POD and POCD, and studies have noted that identifying these deficiencies is critical during the preoperative period so that appropriate preventive strategies can be implemented. Comprehensive geriatric assessment is a useful approach which evaluates a patient's medical, psycho-social, and functional domains objectively. Various screening tools are available for preoperatively identifying patients with cognitive impairment. The Enhanced Recovery After Surgery (ERAS) protocols have been discussed in the context of prehabilitation as an effort to optimize a patient's physical status prior to surgery and decrease the risk of POD and POCD. Evidence-based protocols are warranted to standardize care in efforts to effectively meet the needs of these patients.

The MemTrax Test Compared to the Montreal Cognitive Assessment Estimation of Mild Cognitive Impairment

Cognitive impairment is a leading cause of dysfunction in the elderly. When mild cognitive impairment (MCI) occurs in elderly, it is frequently a prodromal condition to dementia. The Montreal Cognitive Assessment (MoCA) is a commonly used tool to screen for MCI. However, this test requires a face-to-face administration and is composed of an assortment of questions whose responses are added together by the rater to provide a score whose precise meaning has been controversial. This study was designed to evaluate the performance of a computerized memory test (MemTrax), which is an adaptation of a continuous recognition task, with respect to the MoCA. Two outcome measures are generated from the MemTrax test: MemTrax_speed and MemTrax_correct. Subjects were administered the MoCA and the MemTrax test. Based on the results of the MoCA, subjects were divided in two groups of cognitive status: normal cognition (n = 45) and MCI (n = 37). Mean MemTrax scores were significantly lower in the MCI than in the normal cognition group. All MemTrax outcome variables were positively associated with the MoCA. Two methods, computing the average MTX score and linear regression were used to estimate the cutoff values of the MemTrax test to detect MCI. These methods showed that for the outcome MemTrax_speed a score below the range of 0.87 – 91 s^-1 is an indication of MCI, and for the outcome MemTrax_correct a score below the range of 85 – 90% is an indication for MCI.

Postoperative Outcomes in Primary Total Knee Arthroplasty Patients With Preexisting Cognitive Impairment: A Systematic Review

INTRODUCTION

To evaluate the body of evidence on the predictive value of preoperative cognitive impairment on in-hospital, short-term, and midterm postoperative outcomes for elderly patients undergoing total knee arthroplasty (TKA).

SIGNIFICANCE

With an aging population, an increasing percentage of the U.S. patient population will be living with cognitive impairment. There is currently no systematic review that assesses postoperative outcomes of patients with mild cognitive impairment (MCI) or preexisting diagnosis of dementia while undergoing elective primary TKA.

RESULTS

A database search between January 1, 1997, and November 1, 2017 in EMBASE, MEDLINE, and PubMed was conducted to identify articles that compared postoperative outcomes after TKA between patients aged 60 years with and without cognitive impairment. Cognitive impairment included preexisting diagnosis of dementia or MCI identified during preoperative assessment. Eligible articles were selected using dual reviewer and third-party arbitrator. The quality of the studies was evaluated using the Newcastle-Ottawa Scale. The strength of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation approach. A total of 6163 abstracts were screened. Only 11 full text articles met inclusion criteria, including 1 case-control, 5 prospective cohort, and 5 retrospective cohort studies. Two studies were of poor quality. Overall, there is moderate strength of evidence for increased risk of postoperative delirium, increased length of stay, and discharge to health-care facility among patients with preoperative MCI or preexisting dementia. The body of evidence is weak for other outcomes of interest including mortality, functionality and complications while in-hospital and in the short- and midterm.

CONCLUSION

This review highlights the need for additional good quality studies to provide more information about MCI and dementia as risk factors in primary TKA.

Best Practices for Postoperative Brain Health: Recommendations From the Fifth International Perioperative Neurotoxicity Working Group

As part of the American Society of Anesthesiology Brain Health Initiative goal of improving perioperative brain health for older patients, over 30 experts met at the fifth International Perioperative Neurotoxicity Workshop in San Francisco, CA, in May 2016, to discuss best practices for optimizing perioperative brain health in older adults (ie, >65 years of age). The objective of this workshop was to discuss and develop consensus solutions to improve patient management and outcomes and to discuss what older adults should be told (and by whom) about postoperative brain health risks. Thus, the workshop was provider and patient oriented as well as solution focused rather than etiology focused. For those areas in which we determined that there were limited evidence-based recommendations, we identified knowledge gaps and the types of scientific knowledge and investigations needed to direct future best practice. Because concerns about perioperative neurocognitive injury in pediatric patients are already being addressed by the SmartTots initiative, our workshop discussion (and thus this article) focuses specifically on perioperative cognition in older adults. The 2 main perioperative cognitive disorders that have been studied to date are postoperative delirium and cognitive dysfunction. Postoperative delirium is a syndrome of fluctuating changes in attention and level of consciousness that occurs in 20%-40% of patients >60 years of age after major surgery and inpatient hospitalization. Many older surgical patients also develop postoperative cognitive deficits that typically last for weeks to months, thus referred to as postoperative cognitive dysfunction. Because of the heterogeneity of different tools and thresholds used to assess and define these disorders at varying points in time after anesthesia and surgery, a recent article has proposed a new recommended nomenclature for these perioperative neurocognitive disorders. Our discussion about this topic was organized around 4 key issues: preprocedure consent, preoperative cognitive assessment, intraoperative management, and postoperative follow-up. These 4 issues also form the structure of this document. Multiple viewpoints were presented by participants and discussed at this in-person meeting, and the overall group consensus from these discussions was then drafted by a smaller writing group (the 6 primary authors of this article) into this manuscript. Of course, further studies have appeared since the workshop, which the writing group has incorporated where appropriate. All participants from this in-person meeting then had the opportunity to review, edit, and approve this final manuscript; 1 participant did not approve the final manuscript and asked for his/her name to be removed.

Mini-Cog for the diagnosis of Alzheimer's disease dementia and other dementias within a primary care setting

BACKGROUND

Alzheimer's disease and other forms of dementia are becoming increasingly common with the aging of most populations. The majority of individuals with dementia will first present for care and assessment in primary care settings. There is a need for brief dementia screening instruments that can accurately diagnose dementia in primary care settings. The Mini-Cog is a brief, cognitive screening test that is frequently used to evaluate cognition in older adults in various settings.

OBJECTIVES

To determine the diagnostic accuracy of the Mini-Cog for diagnosing Alzheimer's disease dementia and related dementias in a primary care setting.

SEARCH METHODS

We searched the Cochrane Dementia and Cognitive Improvement Register of Diagnostic Test Accuracy Studies, MEDLINE, Embase and four other databases, initially to September 2012. Since then, four updates to the search were performed using the same search methods, and the most recent was January 2017. We used citation tracking (using the databases' 'related articles' feature, where available) as an additional search method and contacted authors of eligible studies for unpublished data.

SELECTION CRITERIA

We only included studies that evaluated the Mini-Cog as an index test for the diagnosis of Alzheimer's disease dementia or related forms of dementia when compared to a reference standard using validated criteria for dementia. We only included studies that were conducted in primary care populations.

DATA COLLECTION AND ANALYSIS

We extracted and described information on the characteristics of the study participants and study setting. Using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) criteria we evaluated the quality of studies, and we assessed risk of bias and applicability of each study for each domain in QUADAS-2. Two review authors independently extracted information on the true positives, true negatives, false positives, and false negatives and entered the data into Review Manager 5 (RevMan 5). We then used RevMan 5 to determine the sensitivity, specificity, and 95% confidence intervals. We summarized the sensitivity and specificity of the Mini-Cog in the individual studies in forest plots and also plotted them in a receiver operating characteristic plot. We also created a 'Risk of bias' and applicability concerns graph to summarize information related to the quality of included studies.

MAIN RESULTS

There were a total of four studies that met our inclusion criteria, including a total of 1517 total participants. The sensitivity of the Mini-Cog varied between 0.76 to 1.00 in studies while the specificity varied between 0.27 to 0.85. The included studies displayed significant heterogeneity in both methodologies and clinical populations, which did not allow for a meta-analysis to be completed. Only one study (Holsinger 2012) was found to be at low risk of bias on all methodological domains. The results of this study reported that the sensitivity of the Mini-Cog was 0.76 and the specificity was 0.73. We found the quality of all other included studies to be low due to a high risk of bias with methodological limitations primarily in their selection of participants.

AUTHORS' CONCLUSIONS

There is a limited number of studies evaluating the accuracy of the Mini-Cog for the diagnosis of dementia in primary care settings. Given the small number of studies, the wide range in estimates of the accuracy of the Mini-Cog, and methodological limitations identified in most of the studies, at the present time there is insufficient evidence to recommend that the Mini-Cog be used as a screening test for dementia in primary care. Further studies are required to determine the accuracy of Mini-Cog in primary care and whether this tool has sufficient diagnostic test accuracy to be useful as a screening test in this setting.