Neuropsychological improvement versus practice effect following unilateral carotid endarterectomy in patients without stroke

Association of joint replacement surgery with incident dementia diagnosis in German claims data

ABSTRACTBackground:Cognitive decline is an important complication of joint replacement surgeries in senior people.

METHODS

We determined incidence rates of dementia diagnosis following endoprosthetic joint replacement surgery (upper and lower extremities). The observation period covered up to 28 quarters using German claims data comprising 154,604 cases 65 years and older. Effects were controlled for cerebrovascular and vascular risk factors, age, sex, the presence of a diagnosis of delirium, and regular prescription of sedative or analgesic drugs (SAD).

RESULTS

The rate of incident dementia diagnoses in people without joint replacement surgery was 21.34 per 1,000 person years, compared with 80.76 incident cases when joint replacement surgery was conducted during the quarter of the incident dementia diagnosis; rates declined to 21.77 incident cases 7 and more quarters after joint replacement surgery had taken place. This pattern was maintained when controlling for delirium diagnosis and regular prescription of SAD. Among 10,563 patients with at least one joint replacement surgery, patients with a diagnosis of delirium in the quarter of the surgery were at increased risk of a dementia diagnosis compared to patients without such a diagnosis (HR=2.00, p < 0.001).

CONCLUSION

In people surviving the high-risk phase for dementia immediately after surgery, long-term risk of dementia may reach the level of those without surgery. These findings encourage consequent perioperative management to reduce the risk of dementia as well as prospective studies of potentially beneficial effects of joint replacement surgery on mid- to long-term recovery of mobility and cognition in geriatric patients.

Severe carotid artery stenosis evaluated by ultrasound is associated with post stroke vascular cognitive impairment

BACKGROUND

Acute ischemic stroke has been recognized as one key cause of vascular cognitive impairment (VCI). The purpose of this study was to evaluate the correlation between carotid artery stenosis and post VCI in acute ischemic stroke patients.

METHODS

In this study, B-mode ultrasound was applied to measure the degree of carotid artery stenosis. After 1 year, the stroke patients' cognitive function was assessed by the mini-mental state examination (MMSE) score. The relationship between the VCI and degree of carotid artery stenosis was evaluated by multivariate regression analysis.

RESULTS

VCI was observed in 136 (37.2%) of the 365 participants. High degree of carotid artery stenosis was significantly correlated with VCI (p < .01), and this correlation remained unchanged even adjustment for age, gender, education level, stroke features, and vascular risk factors.

CONCLUSIONS

These findings indicate that high-grade stenosis of carotid artery is positively correlated with post stroke VCI in patients with acute ischemic stroke. The evaluation of 1 year post stroke cognitive function may be a potential tool for screening stroke patients at risk of VCI.

Neurocognitive Improvement in Patients Undergoing Carotid Endarterectomy for Atherosclerotic Occlusive Carotid Artery Disease

Objectives: To assess the improvement in neurocognitive functions after carotid endarterectomy (CEA) under local anesthesia (LA) in patients with carotid bifurcation occlusive disease. Place and duration of study: Department of Vascular Surgery, Combined Military Hospital Lahore from January 2013 to January 2015. Patients and Methods: A total of 79 patients with carotid artery occlusive disease, having no history of major stroke, depression, or dementia underwent CEA under LA. Cognitive functions were assessed 3 days before surgery and then 4 weeks and 12 weeks after the surgery using the Addenbrookes cognitive examination (ACE) score and General Practitioner Assessment of Cognition (GPCOG) Score. Results: In ACE score, Attention, Memory, Fluency, Language, and Visuospatial orientation improved by 33.3%, 30.7%, 21.4%, 38.4%, and 31.2%, respectively, by the end of 12 weeks. An overall improvement in neurocognition was 32% (P = 0.03). In GPCOG score, Orientation, Recall, and Memory improved by 33%, 20%, and 100%, respectively, with an overall improvement of 33.3% at the end of 12 weeks (P = 0.02). Conclusion: Both scoring systems show an overall improvement in neurocognition as well as improvements in all the subcategories in each system. Hence, we conclude statistically significant improvement in neurocognitive functions after CEA.

Practice Effects on Visuomotor and Problem-Solving Tests by Children

Practice effects on a visuomotor test (the Developmental Test of Visuo-Motor Integration), a timed visual discrimination test (the Underlining Test), and two problem-solving tests (the Porteus Mazes Test and the Tower of Hanoi Test) were analyzed. Children of two age groups ( Ms: 7.7 and 11.6 yr.) were chosen to study the effect of age on practice effects. The tests were repeated nine times with test-retest intervals of 2 mo. The Developmental Test of Visuo-Motor Integration showed no practice effects, while the Porteus Mazes Test, the Underlining Test, and the Tower of Hanoi Test showed significant practice effects. Practice effects were larger for the older age group on all the tests, except the Developmental Test of Visuo-Motor Integration. The Developmental Test of Visuo-Motor Integration and the Underlining Test showed good reliability, but those of the problem-solving tasks were less satisfactory. The stability of all the tests, except the Tower of Hanoi Test, was good.

Test-Retest Stability of the Wisconsin Card Sorting Test

Eighty-seven normal older persons were administered the Wisconsin Card Sorting Test (WCST) on two occasions an average of 1.1 years apart. Means for age and education were 68.79 years ( SD = 6.21) and 14.80 years ( SD = 2.42), respectively. Stability coefficients ranged from .12 on the Learning to Learn scale to .66 for the Total Number of Errors scale. The majority of individuals improved on retest with five WCST scores demonstrating significant average retest gains of 5 to 7 standard score points. The standard error of prediction, standard error of difference, and abnormal test-retest discrepancy scores were calculated to assist clinicians in detecting possible meaningful changes in WCST scores on retest.

Association between Carotid Artery Stenosis and Cognitive Impairment in Stroke Patients: A Cross-Sectional Study

To investigate potential associations between carotid artery stenosis and cognitive impairment among patients with acute ischemic stroke and to provide important clinical implications. We measured the degree of carotid artery stenosis and recorded the Mini-Mental State Examination score (MMSE) at admission in 3116 acute ischemic stroke patients. The association between carotid stenosis and cognitive impairment assessed by MMSE was tested using multivariate regression analysis. Other clinical variables of interest were also studied. After adjusting for age, gender, education level, marriage, alcohol use, tobacco use, physical activity, hypertension, diabetes, hypercholesterolemia, atrial fibrillation, myocardial infarction and NIHSS (National Institutes of Health Stroke Scale) score, we found that participants with high-grade stenosis of the carotid artery had a higher likelihood of cognitive impairment compared to those without carotid artery stenosis (OR = 1.49, 95%CI: 1.05–2.11, p<0.001). Left common carotid artery stenosis was associated with cognitive impairment in the univariate analysis, although this effect did not persist after adjustment for the NIHSS score. Cognitive impairment was associated with high-grade stenosis of the right carotid artery.

Postoperative Cognitive Dysfunction: Minding the Gaps in Our Knowledge of a Common Postoperative Complication in the Elderly

Postoperative cognitive dysfunction (POCD) is a common complication associated with significant morbidity and mortality in elderly patients. There is much interest in and controversy about POCD, reflected partly in the increasing number of articles published on POCD recently. Recent work suggests surgery may also be associated with cognitive improvement in some patients, termed postoperative cognitive improvement (POCI). As the number of surgeries performed worldwide approaches 250 million per year, optimizing postoperative cognitive function and preventing/treating POCD are major public health issues. In this article, we review the literature on POCD and POCI, and discuss current research challenges in this area.

Psychometric and EEG changes after carotid endarterectomy

The influence of carotid stenosis and its surgical treatment on brain function is still poorly defined. We therefore performed a study to assess psychometric and quantified EEG findings after carotid endarterectomy (CEA). Sixty-nine non-demented patients (aged 72 ± 7 years) with severe carotid stenosis (≥ 70%) eligible for CEA were studied. Forty patients (group A) had unilateral stenosis, and 29 patients (group B) had bilateral stenosis. Before and 5 months after CEA all the patients were evaluated by the Trail Making Test A, the Symbol Digit Test, and spectral EEG analysis. At baseline, compared to group A, group B patients performed slowly the Trail Making Test A (Z: 1.45 ± 1.4 vs. 0.76 ± 1.3; p <  0.05), but not the Symbol Digit Test (Z: 0.83 ± 1.38 vs. 0.64 ± 1.26; p = 0.59). Altogether, the patients with at least one abnormal psychometric test were 29% (group A: 26%; group B: 33%, p = 0.56). The EEG did not differ significantly between patients of group A compared to group B. After CEA, psychometric tests improved (mean Z score from 0.73 ± 1.12 to 0.45 ± 1.15, p <  0.05). The improvement was similar in group A and B. The EEG mean dominant frequency improved only in group B patients and it was related to the improvement in psychometric tests (r = 0.43, p = 0.05). Low psychometric performance was detectable in about 1/ 3 of non-demented patients with severe carotid stenosis. CEA improved mental performance and, in patients with severe bilateral stenosis, accelerated the EEG frequency.

The effect of carotid occlusion in cognition before endarterectomy

The role of carotid stenosis on cognition remains to be determined. To study whether people with stenosis of the carotid artery have increased cognitive impairments, we studied 53 patients with moderate or severe carotid stenosis (with no symptoms of stroke or dementia) and 53 controls. We describe which cognitive functions were impaired in the patients and whether there were differences based on the side, the severity of the stenosis or the presence of neurological symptoms. Using the Repeatable Battery for the Assessment of Neuropsychological Status, we found that the patients with carotid stenosis had lower cognitive performances in attention, verbal memory, visuospatial capacity and verbal fluency. Patients with lesser degrees of stenosis than healthy control patients had better scores in learning and memory. The results from this study suggest that patients with severe carotid stenosis have a lower cognitive status than healthy control patients, which is associated with the degree of total carotid stenosis.

Quality of life after carotid endarterectomy

Background

Most studies documenting beneficial outcomes after carotid endarterectomy (CE) are limited to mortality and morbidity rates, costs, and length of hospital stay (LOS). Few have examined the dependency of patients and how they perceive their own health changes after surgery. The aim of the present study was to evaluate quality of life and independence in activities of daily living (ADL) and to study its determinants.

Methods

Sixty-three patients admitted in the Post Anaesthesia Care Unit (PACU) after CE were eligible for this 14-month follow-up study. Patients were contacted 6 months after discharge to complete a Short Form-36 questionnaire (SF-36) and to have their dependency in ADL evaluated.

Results

Among 59 hospital survivors at 6 months follow-up, 43 completed the questionnaires. Sixty-three percent reported that their general level of health was better on the day they answered the questionnaire than 12 months earlier. Patients had worse SF-36 scores for all domains except bodily pain than a general urban population, and comparison with a group of patients 6 months after surgical ICU discharge showed no differences. Six months after PACU discharge, the Lawton Instrumental Activities of ADL Scale and the Katz Index of ADL demonstrated higher dependency scores (5.9 ± 2.2 versus 4.3 ± 2.4 and 0.3 ± 0.8 versus 0.6 ± 0.9, p < 0.001 and p = 0.047). Sixty-five percent and 33% were dependent in at least one activity in instrumental and personal ADL, respectively. Patients dependent in at least one ADL task had higher Revised Cardiac Risk Index (RCRI) scores (1.0 versus 1.5, p = 0.017). After controlling for multiple comparisons, no significant differences were found.

Conclusion

Patients undergoing CE have improved self-perception of quality of life despite being more dependent. Almost all their scores are worse than those in an urban population. We could identify no predictors of greater dependency in ADL tasks six months after PACU discharge.

Testing the laterality hypothesis after left or right carotid endarterectomy: no ipsilateral effects on neuropsychological functioning

Carotid endarterectomy (CEA) is performed to prevent stroke, but the possible restorative function of CEA on neuropsychological functioning has frequently been considered. Restorative effects might be clearer in functions mediated by the hemisphere ipsilateral to the operated side than in those of the contralateral hemisphere. The present study examined this hypothesis, both at group level and at individual level, in 45 right-handed male patients with CEA of either the right or the left carotid artery. Patients with a clinically presented stroke were excluded. Only tasks sensitive to hemispheric specialization were included. Preoperatively, the two patient subgroups performed significantly worse than the healthy control group in the planning of motor behavior, verbal fluency, and visual recognition. Three months after surgery, the mean performance of the patient group increased only in left-hand finger tapping. This was irrespective of the side of surgery and could be attributed to practice. In addition, the number of patients with meaningful cognitive change did not differ between the group with right-sided CEA and the group with left-sided CEA. In conclusion, ipsilateral effects on neuropsychological functioning after CEA were not demonstrated, although instruments and sample characteristics were optimal in light of hemispheric functional asymmetry.

Postoperative cognitive dysfunction: incidence and prevention

Postoperative cognitive dysfunction (POCD) is a decline in cognitive function for weeks or months after surgery. Due to its subtle nature, neuropsychological testing is necessary for its detection. The interpretation of literature on POCD is difficult because of numerous methodological limitations, particularly the different definitions of POCD and the lack of data from control groups. POCD is common after cardiac surgery, and recent studies have now verified that POCD also exists after major non-cardiac surgery, although at a lower incidence. The risk of POCD increases with age, and the type of surgery is also important because there is a very low incidence associated with minor surgery. Regional anaesthesia does not seem to reduce the incidence of POCD, and cognitive function does not seem to improve after carotid surgery as has previously been suggested.

Does carotid endarterectomy improve cognitive functioning?

BACKGROUND

Carotid endarterectomy (CEA) might improve cognitive functioning, but studies thus far have produced mixed results. The aim of the present study was to examine the effect of CEA on cognitive functions in a methodologically more strict design, first by testing the presumption of preoperative cognitive impairment and second through a better control for the possible influence of the nonspecific effects of practice and surgery.

METHODS

Preoperative performance on a neuropsychologic test battery of 56 patients with severe occlusive disease of the carotid artery but without history of major stroke was compared with the performance of 46 healthy control subjects and 23 patients before endarterectomy of the superficial femoral artery (remote endarterectomy). The degree of cognitive change in the 2 patient groups was compared at 3 and 12 months postoperatively. We assessed mood to control for possible momentary affective influences on cognition.

RESULTS

Before CEA, patients showed reduced functioning compared with that seen in healthy control subjects in terms of attention, verbal and visual memory, planning of motor behavior, psychomotor skills, and executive function. Performance of patients before remote endarterectomy was reduced as well. Improvements in several cognitive functions were observed after both types of surgical interventions and were attributed to psychologic relief from uncomplicated surgery and to practice.

CONCLUSIONS

No specific restorative effect of CEA on cognitive functioning was observed. The preoperative impairment in several cognitive domains might be caused by factors that patients with various types of vascular disease might have in common, such as small-vessel disease or other undetected abnormalities within the brain.

Left or right carotid endarterectomy in patients with atherosclerotic disease: Ipsilateral effects on cognition?

We evaluated hemispheric functions ipsilateral to the side of carotid endarterectomy (CEA) in patients with a severe stenosis in the left or right carotid artery. Assessments took place 1 day before and 3 months after CEA. Only right-handed males were included. Nineteen patients underwent surgery of the left carotid artery and 17 of the right. Valid instruments for hemispheric function were included, such as verbal dichotic listening, finger tapping, and a lateralised test for motor planning. Results showed that, preoperatively, patients had lower scores compared to norms on the laterality tests, and on a visuoconstructive test. There was no evidence of ipsilateral improvement related to side of surgery. Left ear dichotic listening improved, which was seen in both left and right surgery groups. Also in both groups, left- and right-hand movement speed in the motor planning test decreased. Conclusion is that beneficial ipsilateral cognitive change after CEA in patients with severe stenosis in one of the carotid arteries may not be demonstrated, even if valid instruments for hemispheric function are included.

The assessment of postoperative cognitive function

Postoperative cognitive function (POCD) has been subject to extensive research. In the literature, large differences are apparent in methodology such as the test batteries, the interval between sessions, the endpoints to be analysed, statistical methods, and how neuropsychological deficits are defined. Traditionally, intelligence tests or tests developed for clinical neuropsychology have been used. The tests for detecting POCD should be based on well-described sensitivity and suitability in relation to surgical patients. In tests using scores, floor/ceiling effects may compromise the evaluation if the tests are either too easy or to difficult. Uncontrolled testing facilities and change of test personnel may affect the test performance. Practice effects are pronounced in neuropsychological tests but have generally been ignored. The use of a suitable normative population is essential to allow correction for practice effects and variability between sessions. Missing follow-up may severely compromise valid conclusions since subjects unable or unwilling to be examined are particularly prone to suffer from POCD. In the statistical analysis of the test results, the evaluation should be based on differences between pre- and postoperative performance. Parametric statistical tests are not relevant unless the appropriate Gaussian distributions are present, perhaps after transformation of data. The definition of cognitive dysfunction should be restrictive and the criteria should be fulfilled in only a small proportion of volunteers. In the literature, these requirements often have not been fulfilled. This precludes a reasonable estimation of the incidence of POCD and the conclusions of comparative studies should be interpreted with great caution. In this review article, we present a number of recommendations for the design and execution of studies within this area. In addition, the critical reader may use these recommendations in the evaluation of the literature.

Subtle brain damage cannot be detected by measuring neuron-specific enolase and S-100beta protein after carotid endarterectomy

OBJECTIVE

To assess whether subtle brain damage after carotid endarterectomy could be detected using serum levels of neuron-specific enolase (NSE) or S-100beta protein.

DESIGN

Prospective noninterventional study.

SETTING

University hospital.

PARTICIPANTS

Twenty-two patients undergoing carotid endarterectomy and 16 patients undergoing repair of abdominal aortic aneurysm.

INTERVENTIONS

Serum levels of NSE and S-100beta protein were measured in all patients before surgery and postoperatively at 12, 24, 36, and 48 hours. In patients undergoing carotid endarterectomy, neuropsychologic testing was performed before surgery and postoperatively at discharge from the hospital and after 3 months using a neuropsychologic test battery.

MEASUREMENTS AND MAIN RESULTS

Compared with abdominal aortic surgery patients, the preoperative serum concentration of NSE was significantly higher in carotid artery surgery patients. Postoperatively, the NSE serum level decreased significantly after uncomplicated carotid artery surgery, and the level was then similar to that in the aortic surgery patients. Before operation, the S-100beta protein levels were similar in the two groups, but a significant increase was seen in aortic surgery patients postoperatively. Neuropsychologic testing after uncomplicated carotid artery surgery revealed cognitive dysfunction in 2 of 20 (10%) of the patients after 5 days and 3 of 16 (19%) of the patients after 3 months. There was no correlation between the change in cognitive function and the changes in blood levels of either NSE or S-100 protein.

CONCLUSIONS

Subtle brain damage after carotid artery surgery could not be detected by measuring blood levels of NSE and S-100beta protein. The NSE level was significantly higher before carotid artery surgery and decreased postoperatively to the level observed in aortic surgery.

Vascular dementia: dead or alive?

The term 'Vascular Dementia' remains popular as a diagnostic entity, since it encompasses a variety of vascular pathologies. This is in stark contrast to many clinical classificatory systems that weight their definitions strongly towards stroke alone. A diagnosis of vascular dementia is complicated by compounding factors that reduce both the validity and specificity of diagnostic systems. This review highlights some of the problems faced in epidemiological, clinical, neuropathological and radiological studies attempting to define a clear-cut syndrome of dementia associated with cerebrovascular disease. The role of non-stroke ischaemia is also discussed. It is concluded that the term vascular dementia may have outlived its usefulness as a valid concept; alternative approaches are suggested.

Effects of practice in repeated administrations of the Wechsler Memory Scale Revised in normal adults

Practice effects were examined over four administrations of the immediate (I) and delayed (II) portions of three subtests of the WMS-R: Logical Memory (LM), Verbal Paired Associates (VPA), and Visual Reproduction (VR). A repeated measures ANOVA revealed that large and significant (p < .001) increases occurred in the General Memory (GM) and Delayed Recall (DR) indices and in the LMI, LMII, and VPAI subtests (Effect Sizes [ESs] = 0.70-0.87). Small but significant (p < .001) increases occurred in VRI (ES = 0.24) and VRII (ES = 0.43). The greatest increase in scores occurred at the first retest session, whereas increases of smaller magnitudes occurred at Sessions 3 and 4. Ceiling effects occur in subtests (VPAII, VRI, and VRII) on which individuals score most of the total possible points at the first testing session; this makes interpretation of practice effects difficult. Test-retest reliability coefficients, mean change scores from Session 1 to Session 2, standard errors of prediction, and 95% confidence intervals are presented. These score changes need to be taken into consideration when interpreting performance at retest.

Health-related quality of life after transient ischemic attack and minor stroke: Is medical or surgical treatment influential?

Although randomized trials have proven the benefit of carotid endarterectomy (CEA) for appropriate patients, health care purchasers increasingly look beyond clinical outcome toward measures of cost effectiveness and health-related quality of life (HRQoL) in apportioning limited resources. We used a generic HRQoL outcome scale, the Short Form 36 (SF-36), to assess the differences in patient-perceived HRQoL in two cohorts of patients who had suffered minor cerebral ischemic events. One group (n=100) had undergone CEA, whereas members of the second cohort (n=100) were not appropriate candidates for surgery and were therefore treated with best medical therapy. The overall response rate was 83%. No significant difference in health profile between the CEA and medical cohorts was detected for the eight SF-36 domains. However, the CEA cohort rated a significantly improved change in general health over the previous year compared with the group managed medically (P<.01). A greater proportion of the former group than of the medical group thought their treatment had been successful and that their health had been improved by treatment (P<.01). Both groups shared the same anxieties over future cerebral ischemic events (P=.3). Patients' perception of HRQoL measured by the SF-36 domains was almost identical between the CEA and medical cohorts apart from a small but significant improvement in self-reported overall health in the CEA cohort. HRQoL outcome measures may be of value in future clinical trials of cerebral revascularization.

Effect of repeated administration of a neuropsychological battery in the elderly

Our study explored the magnitude of practice effect in repeated administration of NP measures that tap different cognitive domains in normal elderly subjects (N = 122) between ages 57 and 85, who were evaluated over three annual testing probes. Results revealed that WAIS-R PIQ, serial recall of words, WMS visual memory, and memory for logical passages (immediate and delayed) are likely to improve on the retest due to practice effect in individuals below age 75, whereas test-retest changes in older people show a different pattern. Implications of age-specific changes on retest for differential diagnosis of dementia in clinical practice were considered.

Neuropsychological deficits in asymptomatic carotid artery stenosis

A total of 20 subjects with asymptomatic carotid artery stenosis (ACAS) and a group of healthy controls were compared as to their cognitive performance. Subjects with ACAS showed substantial deficits on tasks of mental speed, learning, visuospatial abilities, verbal processing and deductive reasoning. The cognitive profile of ACAS--subjects indicated non-specific impairment, possibly related to widespread cerebral vascular disease, of which the presence of ACAS may be one indicator.

"Practice makes perfect:" retest effects in college athletes

Retest effects on a diverse set of neuropsychological measures were established using a normal sample comprised of college athletes (N = 110). Results suggest that retest effects vary depending on the type of test used, but the magnitude of effect on individual tests can be quite large. Implications of using tests with large retest effects or tests without established retest effect sizes are discussed.