A.M.A. Brands

The Backward Span of the Corsi Block-Tapping Task and Its Association With the WAIS-III Digit Span

The Corsi Block-Tapping Task measures visuospatial short-term and working memory, but a standardized backward condition is lacking. The authors present a standardized backward procedure that was examined in 246 healthy older adults (ages 50 to 92), comparing the results with the Digit Span subtest of the Wechsler Adult Intelligence Scale— Third Edition. Principal component analysis resulted in a two-factor model, dissociating a verbal and a spatial working-memory factor. Also the Corsi backward is not more difficult than the Corsi forward, in contrast to the Digit Span backward that is more difficult than the Digit Span forward. This may suggest that the Corsi Block-Tapping Task backward task relies on processing within working-memorys slave systems, whereas the Digit Span backward also relies on the central executive component of working memory. Finally, regression-based normative data and cutoff scores for older adults are presented for use in clinical practice.

Cognitive Performance, Psychological Well-Being, and Brain Magnetic Resonance Imaging in Older Patients With Type 1 Diabetes

Modest cognitive impairment has been reported in young-adult patients with type 1 diabetes. In older patients with type 2 diabetes, cognitive impairments are more pronounced, which might be due to age but also to differential effects of type 1 diabetes and type 2 diabetes on the brain. This study therefore assessed cognitive performance and magnetic resonance imaging (MRI) of the brain in older type 1 diabetic patients. Forty type 1 diabetic patients (age >50 years) and 40 age-matched control subjects were included. Neuropsychological assessment included all major cognitive domains, and psychological well-being was assessed with questionnaires. Atrophy, white-matter abnormalities, and infarcts were rated on MRI scans. Type 1 diabetic patients performed slightly (effect sizes <0.4) worse on cognitive tasks, but only “speed of information processing” reached statistical significance. No significant between-group differences were found on any of the MRI parameters. Type 1 diabetic patients tended to report more cognitive and depressive problems than control subjects, but this did not correlate with the performance on cognitive tests. We conclude that cognition in older type 1 diabetic patients is only mildly disturbed. Chronic exposure to hyperglycemia is in itself, even at older age, apparently not sufficient to have considerable impact on the brain.

A detailed profile of cognitive dysfunction and its relation to psychological distress in patients with type 2 diabetes mellitus

Type 2 diabetes mellitus (DM2) is a common metabolic disorder. DM2 is associated with cognitive impairments, and with depressive symptoms, which occur in about one third of patients. In the current study we compared the cognitive profile and psychological well-being of 119 patients with DM2 (mean age: 66 +/- 6; mean duration: 9 +/- 6 years) with 55 age and education matched-control participants. Groups were compared on cognitive performance in five major cognitive domains, psychological wellbeing [assessed by Symptom Checklist (SCL)-90-R and the Beck Depression Inventory (BDI-II)] and abnormalities on brain MRI. We hypothesized an interrelationship between cognition, MRI abnormalities, and psychological well-being. DM2 patients performed significantly worse than controls on cognitive tasks, especially on tasks that required more mental efficiency, although the differences were modest (effect sizes Cohen d < .6). We speculate that DM2 patients have a diminished ability to efficiently process unstructured information. Patients with DM2 had significantly higher scores on the SCL-90-R (p < .001) and on the BDI-II (p < .001) and worse MRI ratings than controls, but psychological distress did not correlate with cognition, MRI ratings or biomedical characteristics. Contrary to our hypothesis, cognitive disturbances and psychological distress thus seem independent symptoms of the same disease.

Cognitive Functioning and Brain MRI in Patients with Type 1 and Type 2 Diabetes Mellitus: A Comparative Study

Background/Aims: Diabetes mellitus (DM) may affect the central nervous system, resulting in cognitive impairments. It has been suggested that cognitive impairments are more pronounced in DM2 than in DM1, but studies that directly compare the effects of these 2 types of DM on cognition are lacking. Methods: Forty patients with DM1 (mean duration: 34 years) were compared with 40 age- and education-matched patients who were known to have DM2 (mean duration: 7 years). Extensive neuropsychological assessment focussed on abstract reasoning, memory, attention and executive function, visuoconstruction and information processing speed. Psychological well-being was measured and brain MRIs were obtained. Results:No systematic between-group differences were observed in neuropsychological measures or levels of psychological well-being. DM2 patients showed significantly more deep white matter lesions and cortical atrophy on MRI (p < 0.01). Conclusion: DM1 patients with more than 30 years of DM have a similar cognitive profile and better MRI ratings than age- and education-matched DM2 patients with only 7 years of DM.

The Brixton Spatial Anticipation Test as a test for executive function: validity in patient groups and norms for older adults.

Impairments in executive functioning frequently occur after acquired brain damage, in psychiatric disorders, and in relation to aging. The Brixton Spatial Anticipation Test is a relatively new measure for assessing the ability to detect and follow a rule, an important aspect of executive functioning. To date, normative data on this task are limited, particularly concerning the elderly. This study presents age- and education-adjusted regression-based norms obtained in a group of healthy older participants (n = 283; mean age 67.4 +/- 8.5 years). The applicability and validity of these norms were further examined in different groups of patients with stroke (n = 106), diabetes mellitus (n = 376), MCI/early dementia (n = 70), psychiatric disorders (n = 63), and Korsakoffs syndrome (n = 41). The results showed that patients with Korsakoffs syndrome, stroke, and psychiatric disorders performed significantly worse than healthy controls. Test-retest correlation (n = 83), learning effects, and correlations with other neuropsychological tests were also explored. Based on the present study, the Brixton test appears a useful addition to existing measures of executive functioning. Moreover, the test can be reliably applied in different groups of clinical patients.

Relationship between Working Hours and Power of Attention, Memory, Fatigue, Depression and Self-Efficacy One Year after Diagnosis of Clinically Isolated Syndrome and Relapsing Remitting Multiple Sclerosis

The role of cognitive domain dysfunction with respect to vocational changes in persons with Clinically Isolated Syndrome (CIS) and early Relapsing Remitting Multiple Sclerosis (eRRMS) is insufficiently known. We investigated thirty-three patients - 14 CIS, 19 eRRMS -, mean (standard deviation [SD]) time since diagnosis 13.5 (4.8) months and mean (SD) Expanded Disability Status Scale (EDSS) score 1.3 (1.1). Patients were assessed on the CDR System, a set of automated tests of cognitive function, which yielded scores for Power of Attention (ms), Continuity of Attention (#), Working Memory (SI), Episodic Memory (#) and Speed of Memory (ms). Work-related items and the confounding variables fatigue, depression, disease impact and self-efficacy, were assessed by self-report questionnaires. Patients had poorer Power of Attention compared to normative data (1187 [161.5] vs. 1070 [98.6]; P<0.0001) and slower Speed of Memory (4043 [830.6]) vs. 2937 [586.1]; P<0.0001). Power of Attention (Pearson r = −0.42; P<0.04), Working Memory (r = 0.42; P<0.04) and depression r = −0.41; P<0.05) correlated with number of days worked per week. Fatigue (r = −0.56; P<0.005), self-efficacy (r = 0.56; P<0.005) and disease impact (r = −0.46; P<0.05) correlated with number of hours worked per week. Persons who wished to work less had poorer Power of Attention (1247 vs. 1116 ms; P<0.02), those who wished to change job had poorer Episodic Memory (1.35 vs. 1.57; p<0.03). People who reduced working hours within 12 months after diagnosis had higher fatigue and disease impact, and lower self-efficacy. The findings of this pilot study indicate that one year after the diagnosis of CIS and RRMS Power of Attention and Speed of Memory are reduced, that Power of Attention and Memory are associated with a capability of working less hours, and that fatigue, depression and disease impact may negatively, and self-efficacy positively affect working hours.

Cognition in Older Patients with Type 1 Diabetes Mellitus: A Longitudinal Study

reasoning 0.06 ( 0.19 to 0.30) 0.24 ( 0.14 to 0.62) .08 Memory 0.001 ( 0.11 to 0.11) 0.05 ( 0.25 to 0.14) .01 Information processing speed 0.12 ( 0.25 to 0.02) 0.38 ( 0.711 to 0.050) .54 Attention and executive function 0.17 ( 0.40 to 0.06) 0.10 ( 0.35 to 0.14) .93 Visuoconstruction 0.20 ( 0.45 to 0.04) 0.40 (0.13 to 0.67) .44 Cardiovascular events§,k Overall cognitive functioning 0.11 ( 0.28 to 0.05) 0.10 ( 0.24 to 0.45) .04 Information processing speed 0.34 ( 0.65 to 0.03) 0.05 ( 0.77 to 0.88) .05 Severe hypoglycemic events Overall cognitive functioning 0.01 ( 0.12 to 0.24) 0.38 ( 0.70 to 0.05) .87 Information processing speed 0.19 ( 0.40 to 0.01) 0.67 ( 1.21 to 0.14) .04 Mean change in z-scores over time for the whole group. Negative values indicate poorer performance at follow-up than at baseline. Mean difference in z-scores between people with type 1 diabetes mellitus (T1DM) and controls (upper half table) or patients with and without events (lower half table). Negative values indicate poorer performance for the people with T1DM than controls or for participants with events than for those without. zInteraction represent the P-value of the time group interaction. The analyses of cardiovascular and hypoglycemic events only concern the group with T1DM and reflect the differences between patients with and without these events. k Cardiovascular events (7 events in 6 patients) between baseline and follow-up were self-reported stroke (n 5 1), myocardial infarction (n 5 1), percutaneous angioplasty treatment (n 5 1), and angina pectoris (n 5 4). Severe hypoglycemic events (17 events in 12 patients) were self-reported between baseline and follow-up and were defined as events needing assistance to treat loss of consciousness or coma. 564 LETTERS TO THE EDITOR MARCH 2011–VOL. 59, NO. 3 JAGS

Cognition in Adults with Type 1 Diabetes

In this chapter, the literature on the neuropsychology of type 1 diabetes is reviewed. First, the pattern and magnitude of cognitive impairments in adults with type 1 diabetes are discussed. Cognitive decrements are limited to only some cognitive domains and can best be characterised as a slowing of mental speed and a diminished mental flexibility, whereas learning and memory are generally spared. Also, the cognitive decrements are mild in magnitude (i.e. within 0.5 SD of the mean of the control group) and seem neither to be progressive over time, nor to be substantially worse in older adults. Next, we focus on the results of neuroimaging studies. These studies suggest that type 1 diabetic patients have relatively subtle reductions in brain volume but these structural changes may be more pronounced in patients with an early disease onset. Furthermore, we will highlight several possible risk factors and confounding variables, including psychiatric comorbidity, recurrent hypoglycaemia, and chronic hyperglycaemia, and we will address the apparent paradox between evidence of end-organ damage in the brain as a result of diabetes versus evidence of cognitive resilience. Finally, we will discuss the implications of these findings for understanding their effects on daily life.

Exploration of the Raven APM - National Adult Reading Test discrepancy as a measure of intellectual decline in older persons

Previous studies have shown that the discrepancy between performance on “fluid” and “crystallized” intelligence measures may serve as an indicator for intellectual decline. The validity of this procedure in older persons is unknown. The present study developed a multiple regression equation, to predict the Raven Advanced Progressive Matrices (APM) score from the National Adult Reading Test (NART) score and demographic variables in a large sample of healthy older persons (n = 270). The discrepancy between the predicted and observed Raven APM scores was transformed into a percentile distribution as an indicator of intellectual decline, which can be used in clinical practice. The validity of the procedure was further examined by comparing the proportion of persons with a significant decline (at the −1 and −1.65 SD level) between two older patient samples (87 patients with cerebral stroke and 387 patients with diabetes mellitus) by means of χ2 tests. There was a significantly higher rate of intellectual decline at the −1 SD (“below average”) and −1.65 SD (“impaired”) cutoff levels for patients with stroke compared with patients with diabetes (stroke, 34% and 14%; diabetes, 16% and 5%, p < .05). These findings suggest that the Raven APM–NART discrepancy may be a useful measure of intellectual decline in older persons.