Prevalence of mild cognitive impairment subtypes in patients attending a memory outpatient clinic—comparison of two modes of mild cognitive impairment classification. Results of the Vienna Conversion to Dementia Study

Olfactory identification, cognition, depressive symptoms, and 5-year mortality in patients with subjective cognitive decline, mild cognitive impairment, and Alzheimer's disease

OBJECTIVE

An association between odor and cognitive impairment has been shown in many studies. The objective of the present hospital-based, single-center retrospective study was to assess the impact of odor impairment on the mortality of patients with Alzheimer's disease (AD), subjective cognitive decline (SCD), and mild cognitive impairment (MCI).

METHODS

Odor function was measured by Sniffin Sticks (Burghart Messtechnik, Holm, Germany) and the assessment of self-reported olfactory functioning and olfaction-related quality of life (ASOF) test. Cognitive performance was assessed by an extensive neuropsychological test battery, symptoms of depression were diagnosed with the Geriatric Depressive Scale (GDS). The influence of demographic factors such as gender, age, and education were examined.

RESULTS

Although the univariate analyses and pairwise post hoc comparison showed significant differences for some of the olfactory performance tests/subtests, the multivariate models showed no association between olfactory test performance and mortality among patients with cognitive impairment. "Attention," a domain of the Neuropsychological Test Battery Vienna (NTBV), as well as depressive symptoms, gender, and age, showed a significant influence on the mortality of the patient group.

CONCLUSION

Lower olfactory performance showed no impact on mortality. However, decreased cognitive function of "Attention" can be considered as an influential predictor for mortality.

Prevalence, cognitive characteristics, and influencing factors of amnestic mild cognitive impairment among older adults residing in an urban community in Chengdu, China

Objective

Dementia is a significant public health concern, and mild cognitive impairment (MCI) serves as a transitional stage between normal aging and dementia. Among the various types of MCI, amnestic MCI (aMCI) has been identified as having a higher likelihood of progressing to Alzheimer's dimension. However, limited research has been conducted on the prevalence of aMCI in China. Therefore, the objective of this study is to investigate the prevalence of aMCI, examine its cognitive characteristics, and identify associated risk factors.

Methods

In this cross-sectional study, we investigated a sample of 368 older adults aged 60 years and above in the urban communities of Chengdu, China. The participants underwent a battery of neuropsychological assessments, including the Mini-Mental State Examination (MMSE), the Clinical Dementia Rating (CDR), Auditory Verbal Learning Test (AVLT), Wechsler's Logical Memory Task (LMT), Boston Naming Test (BNT) and Trail Making Test Part A (TMT-A). Social information was collected by standard questionnaire. Multiple logistic regression analysis was utilized to screen for the risk and protective factors of aMCI.

Results

The data analysis included 309 subjects with normal cognitive function and 59 with aMCI, resulting in a prevalence of 16.0% for aMCI. The average age of participants was 69.06 ± 7.30 years, with 56.0% being females. After controlling for age, gender and education, the Spearman partial correlation coefficient between various cognitive assessments and aMCI ranged from -0.52 for the long-term delayed recall scores in AVLT to 0.19 for the time-usage scores in TMT-A. The results indicated that all cognitive domains, except for naming scores (after semantic cue of BNT) and error quantity (in TMT-A), showed statistically significant associations with aMCI. Furthermore, the multiple logistic regression analysis revealed that older age (OR = 1.044, 95%CI: 1.002~1.087), lower educational level, and diabetes (OR = 2.450, 95%CI: 1.246~4.818) were risk factors of aMCI.

Conclusion

This study found a high prevalence of aMCI among older adults in Chengdu, China. Individuals with aMCI exhibited lower cognitive function in memory, language, and executive domains, with long-term delayed recall showing the strongest association. Clinicians should prioritize individuals with verbal learning and memory difficulties, especially long-term delayed recall, in clinical practice.

Neurocognitive testing in predicting conversion to Alzheimer's disease

Introduction

Alzheimer’s disease (AD) is a neurodegenerative disorder that affects memory, thinking, attention, and emotion or AD. Smelling problems are frequent symptoms of dementia. The aim of this study was to evaluate whether it is possible to predict if someone with anosmia or hyposmia has a higher risk of getting dementia or even AD.

Methods

This study was a retrospective longitudinal study, and the data used were part of a larger research project, the Vienna Conversion to Dementia Study. The 173 participants were divided into four groups based on cognitive features such as healthy control (HC), subjective cognitive decline (SCD), non-amnestic mild cognitive impairment (naMCI), and amnestic mild cognitive impairment (aMCI). Olfactory assessment and neurocognitive assessment were administered.

Results

We found that 30.5% of aMCI patients converted into AD after an average of about two years. The corresponding ROC analyses for olfactory testing showed that Sniffin’ Sticks revealed significant results regarding the conversion to AD, whereas the Assessment of Self-Reported Olfactory Functioning and olfaction-related quality of life (ASOF) inventory using the Subjective Olfactory Capability (SOC) subscale, the Smell-Related Problems (SRP) subscale, and the Olfaction-Related Quality of life (ORQ) did not. A logistic regression showed that among the olfactory test procedures, only the Sniffin’ Sticks enabled a relevant prognosis. Including neurocognitive measures in the model, only VSRT and the Trail Making Test-B. The other predictors did not contribute to the prediction of conversion to AD.

Conclusion

Unlike self-reporting of olfactory functioning, olfactory testing using standardized tests may have potential for predicting dementia, especially AD. However, olfactory tests have lower predictive power than neurocognitive tests such as verbal memory and divided attention tests.

Implications

Diagnostic tools for predicting dementia as accurately and early as possible are important. Olfactory assessment, compared to neurocognitive tests for verbal memory and divided attention, is inferior in predicting the prognosis of AD.

Real-world applicability of glial fibrillary acidic protein and neurofilament light chain in Alzheimer's disease

Background: Blood-based biomarkers may add a great benefit in detecting the earliest neuropathological changes in patients with Alzheimer's disease (AD). We examined the utility of neurofilament light chain (NfL) and glial fibrillary acidic protein (GFAP) regarding clinical diagnosis and differentiation between amyloid positive and negative patients. To evaluate the practical application of these biomarkers in a routine clinical setting, we conducted this study in a heterogeneous memory-clinic population. Methods: We included 167 patients in this retrospective cross-sectional study, 123 patients with an objective cognitive decline [mild cognitive impairment (MCI) due to AD, n = 63, and AD-dementia, n = 60] and 44 age-matched healthy controls (HC). Cerebrospinal fluid (CSF) and plasma concentrations of NfL and GFAP were measured with single molecule array (SIMOA®) technology using the Neurology 2-Plex B kit from Quanterix. To assess the discriminatory potential of different biomarkers, age- and sex-adjusted receiver operating characteristic (ROC) curves were calculated and the area under the curve (AUC) of each model was compared. Results: We constructed a panel combining plasma NfL and GFAP with known AD risk factors (Combination panel: age+sex+APOE4+GFAP+NfL). With an AUC of 91.6% (95%CI = 0.85-0.98) for HC vs. AD and 81.7% (95%CI = 0.73-0.90) for HC vs. MCI as well as an AUC of 87.5% (95%CI = 0.73-0.96) in terms of predicting amyloid positivity, this panel showed a promising discriminatory power to differentiate these populations. Conclusion: The combination of plasma GFAP and NfL with well-established risk factors discerns amyloid positive from negative patients and could potentially be applied to identify patients who would benefit from a more invasive assessment of amyloid pathology. In the future, improved prediction of amyloid positivity with a noninvasive test may decrease the number and costs of a more invasive or expensive diagnostic approach.

Blood copper excess is associated with mild cognitive impairment in elderly Chinese

BACKGROUND

Copper is associated with mild cognitive impairment (MCI). However, there is a lack of relevant population studies with large sample sizes.

AIMS

This study used baseline data from a cohort study to determine the distribution characteristics of MCI in the elderly and to estimate the association between whole blood copper concentrations and MCI.

METHODS

MCI status was screened by the Mini-Mental State Examination (MMSE) scale and Activities of Daily Living (ADL) scale. The concentration of copper in whole blood was determined by Inductively Coupled Plasma Mass Spectrometer (ICP-MS).

RESULTS

A total of 1057 subjects with an average age of 71.82 ± 6.45 years were included in this study. There were 215 patients with MCI, and the prevalence of MCI was 20.34%. After adjusting for general demographic variables, logistic regression analysis showed that the risk of MCI in the elderly with high copper level was 1.354 times higher than that in the elderly with low copper level (OR 1.354, 95% CI 1.047-1.983, P = 0.034).

CONCLUSION

In this study, it was found that the prevalence of MCI was different in gender, age, education level and other aspects, and a higher copper level in the elderly was significantly related to the occurrence of MCI. The association was stronger in older adults and men.

The role of disability and depressive symptoms in the relation between objective cognitive performance and subjective cognitive decline

BACKGROUND

Subjective cognitive decline (SCD) and subjective memory decline (SMD) are common among older people. Evidence linking SCD and SMD with cognitive and memory impairment is inconsistent. Moreover, little is known about the associations of SCD and SMD with disability. We aimed to explore the associations of SCD and SMD with objective cognitive and memory performance, disability, and depressive symptoms.

MATERIALS AND METHODS

In a cross-sectional study we conducted face to face interviews in a randomized sample of people aged ≥65 years living in the Canton of Ticino, southern Switzerland, between May 2021 and April 2022. We measured subjective cognitive decline with the MyCog, a subsection of the Subjective Cognitive Decline Questionnaire (SCD-Q); cognitive functioning with the Community Screening Instrument for Dementia; memory with the consortium to establish a registry for alzheimer's disease (CERAD) 10-word list learning task; and disability and depressive symptoms with the world health organization disability assessment schedule 2.0 (WHO-DAS 2.0) and the Euro-Depression (EURO-D) scales, respectively.

RESULTS

Of the 250 participants 93.6% reported at least one cognitive difficulty, and 40.0% SMD. Both SCD and SMD were associated with poorer objective cognitive/memory performance, and independently with greater disability, and more depressive symptoms. But in participants with high disability and depressive symptoms subjective and objective cognition were no longer associated. Disability fully mediated the associations of poorer objective cognitive and memory performance with subjective cognitive and memory decline.

CONCLUSION

Routine clinical assessments of cognitive function should include formal enquires about SCD and SMD, and also account for disability and depressive symptoms.

Socially desirable responding in geriatric outpatients with and without mild cognitive impairment and its association with the assessment of self-reported mental health

Background

Socially desirable responding is a potentially relevant issue in older adults and can be evaluated with the Marlowe-Crowne Social Desirability Scale (MCSDS). However, the eight-item MCSDS has never been specifically administered to geriatric subjects, and there is a dearth of literature on the relationship between social desirability and cognitive impairment. Also, the connection between social desirability and subjective measures of psychological well-being is a matter of controversy. This study has three main aims. First, to determine the psychometric properties of the eight-item MCSDS in geriatric outpatients without dementia (i.e. with normal cognition (NC) or mild cognitive impairment (MCI)). Second, to investigate the link between social desirability and cognitive functioning. Third, to determine the association between social desirability and the assessment of self-reported mental health.

Methods

Community-dwelling outpatients (aged ≥ 65) were consecutively recruited and neuropsychologically tested to diagnose NC or MCI (n = 299). Social desirability was assessed with the eight-item MCSDS. Depressive and anxiety symptoms were measured with the short Geriatric Depression (GDS-s) and the State-Trait Personality Inventory Trait Anxiety (STPI-TA) scales.

Results

On principal components analysis, the eight-item MCSDS was found to have a multidimensional structure. Of the initial three-component solution, only two subscales had acceptable internal consistency (Cronbach’s alpha > 0.6): “Acceptance of responsibility” and “Integrity”. The third subscale (“Kindness towards others”) appeared to gauge two distinct constructs of formal (i.e. politeness) versus substantive (i.e. forgiveness) compassion. On binary logistic regression, only higher income was a significant predictor of formal compassion. Test-retest reliability was substantial to excellent (Gwet’s AC2 ≥ 0.8). There were no meaningful differences in social desirability between the NC and MCI groups. Likewise, negative Spearman’s correlations between social desirability and cognitive Z-scores across the whole sample were weak (r_s < |0.3|) and confined to one MCSDS item. Although social desirability was an independent predictor of the STPI-TA score in multiple linear regression, it explained only a marginal amount of incremental variance in anxiety symptoms (less than 2%).

Conclusions

Our results suggest that social desirability need not be a major concern when using questionnaires to assess mental health in geriatric outpatients without dementia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02435-z.

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

BACKGROUND

The diagnosis of Alzheimer's disease dementia and other dementias relies on clinical assessment. There is a high prevalence of cognitive disorders, including undiagnosed dementia in secondary care settings. Short cognitive tests can be helpful in identifying those who require further specialist diagnostic assessment; however, there is a lack of consensus around the optimal tools to use in clinical practice. The Mini-Cog is a short cognitive test comprising three-item recall and a clock-drawing test that is used in secondary care settings.

OBJECTIVES

The primary objective was to determine the accuracy of the Mini-Cog for detecting dementia in a secondary care setting. The secondary objectives were to investigate the heterogeneity of test accuracy in the included studies and potential sources of heterogeneity. These potential sources of heterogeneity will include the baseline prevalence of dementia in study samples, thresholds used to determine positive test results, the type of dementia (Alzheimer's disease dementia or all causes of dementia), and aspects of study design related to study quality.

SEARCH METHODS

We searched the following sources in September 2012, with an update to 12 March 2019: Cochrane Dementia Group Register of Diagnostic Test Accuracy Studies, MEDLINE (OvidSP), Embase (OvidSP), BIOSIS Previews (Web of Knowledge), Science Citation Index (ISI Web of Knowledge), PsycINFO (OvidSP), and LILACS (BIREME). We made no exclusions with regard to language of Mini-Cog administration or language of publication, using translation services where necessary.

SELECTION CRITERIA

We included cross-sectional studies and excluded case-control designs, due to the risk of bias. We selected those studies that included the Mini-Cog as an index test to diagnose dementia where dementia diagnosis was confirmed with reference standard clinical assessment using standardised dementia diagnostic criteria. We only included studies in secondary care settings (including inpatient and outpatient hospital participants).

DATA COLLECTION AND ANALYSIS

We screened all titles and abstracts generated by the electronic database searches. Two review authors independently checked full papers for eligibility and extracted data. We determined quality assessment (risk of bias and applicability) using the QUADAS-2 tool. We extracted data into two-by-two tables to allow calculation of accuracy metrics for individual studies, reporting the sensitivity, specificity, and 95% confidence intervals of these measures, summarising them graphically using forest plots.

MAIN RESULTS

Three studies with a total of 2560 participants fulfilled the inclusion criteria, set in neuropsychology outpatient referrals, outpatients attending a general medicine clinic, and referrals to a memory clinic. Only n = 1415 (55.3%) of participants were included in the analysis to inform evaluation of Mini-Cog test accuracy, due to the selective use of available data by study authors. There were concerns related to high risk of bias with respect to patient selection, and unclear risk of bias and high concerns related to index test conduct and applicability. In all studies, the Mini-Cog was retrospectively derived from historic data sets. No studies included acute general hospital inpatients. The prevalence of dementia ranged from 32.2% to 87.3%. The sensitivities of the Mini-Cog in the individual studies were reported as 0.67 (95% confidence interval (CI) 0.63 to 0.71), 0.60 (95% CI 0.48 to 0.72), and 0.87 (95% CI 0.83 to 0.90). The specificity of the Mini-Cog for each individual study was 0.87 (95% CI 0.81 to 0.92), 0.65 (95% CI 0.57 to 0.73), and 1.00 (95% CI 0.94 to 1.00). We did not perform meta-analysis due to concerns related to risk of bias and heterogeneity.

AUTHORS' CONCLUSIONS

This review identified only a limited number of diagnostic test accuracy studies using Mini-Cog in secondary care settings. Those identified were at high risk of bias related to patient selection and high concerns related to index test conduct and applicability. The evidence was indirect, as all studies evaluated Mini-Cog differently from the review question, where it was anticipated that studies would conduct Mini-Cog and independently but contemporaneously perform a reference standard assessment to diagnose dementia. The pattern of test accuracy varied across the three studies. Future research should evaluate Mini-Cog as a test in itself, rather than derived from other neuropsychological assessments. There is also a need for evaluation of the feasibility of the Mini-Cog for the detection of dementia to help adequately determine its role in the clinical pathway.

Associations of subjective cognitive and memory decline with depression, anxiety, and two-year change in objectively-assessed global cognition and memory

Research studies exploring the association of cognitive complaints with objectively assessed cognitive decline report inconsistent results. However, many of these have methodological limitations. We investigated whether 1) more severe subjective cognitive decline (SCD) and subjective memory decline (SMD) predict change in objectively assessed global cognition, remote memory, recent memory, learning; 2) the predictive value of more severe SMD over change in objectively assessed remote memory, recent memory, and learning is stronger for individuals that report an SMD that started within the past five years than for those that report an SMD that started five or more years previously and/or stronger for those that experienced SMD within the past two years than for those who had not; and 3) greater depression and anxiety are associated with more severe SCD and SMD. We used two-year longitudinal data from the CFAS-Wales study (N = 1,531; mean (SD) age = 73.0 (6.0) years). We fitted linear regression models. More severe SCD and SMD did not predict change in objectively assessed global cognition, remote memory, and recent memory but predicted lower scores in learning. The prediction of SMD over change in learning was not stronger when individuals reported an SMD that started within the past five years compared to when they reported an SMD that started five or more years previously nor when individuals reported an SMD that started within the past two years than those who did not. Greater depression and anxiety were associated with more severe SCD and SMD. More severe SMD may be useful for predicting lower learning ability and for identifying individuals experiencing depression and anxiety.

Individual cognitive changes in subjective cognitive decline, mild cognitive impairment and Alzheimer's disease using the reliable change index methodology

Objective

The development of Alzheimer’s disease (AD) can be assessed using the neuropsychological test battery Vienna (NTBV). The objective of this study was to investigate whether the NTBV test scores of a diagnostic group have changed significantly over time and whether this change is due to disease progression.

Methods

In this study 358 patients referred to a memory outpatient clinic because of cognitive deterioration were analyzed. The same patients were surveyed in a follow-up assessment after a mean interval of 25.96 months to examine cognitive performance and disease progression. Patients were divided into the subgroups healthy controls (HC), subjective cognitive decline (SCD), mild cognitive impairment (MCI) and AD on the basis of the test results. Reliable change index methodology was used to assess improvement or deterioration in test scores in diagnostic groups compared to HC.

Results

Deterioration in the SCD group ranged from 0% to 18.8%. The MCI group showed declines between 1.6% and 29.1%. Patients who developed AD deteriorated between 0% and 54.2%. Improvements ranged from 0% to 73.4% in the SCD group and from 0% to 25.1% for the MCI group. The improvement in the AD group ranged between 0% and 44.0%.

Conclusion

The results reflect the cognitive deterioration of patients during the disease progression. Nevertheless, improvements in diagnostic groups could be detected. The significantly positive changes might be due to practice effects, also a lack of motivation or attention in the first test could have yielded “improvement” in the retest.

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

BACKGROUND

The diagnosis of Alzheimer's disease dementia and other dementias relies on clinical assessment. There is a high prevalence of cognitive disorders, including undiagnosed dementia in secondary care settings. Short cognitive tests can be helpful in identifying those who require further specialist diagnostic assessment; however, there is a lack of consensus around the optimal tools to use in clinical practice. The Mini-Cog is a short cognitive test comprising three-item recall and a clock-drawing test that is used in secondary care settings.

OBJECTIVES

The primary objective was to determine the diagnostic accuracy of the Mini-Cog for detecting Alzheimer's disease dementia and other dementias in a secondary care setting. The secondary objectives were to investigate the heterogeneity of test accuracy in the included studies and potential sources of heterogeneity. These potential sources of heterogeneity will include the baseline prevalence of dementia in study samples, thresholds used to determine positive test results, the type of dementia (Alzheimer's disease dementia or all causes of dementia), and aspects of study design related to study quality.

SEARCH METHODS

We searched the following sources in September 2012, with an update to 12 March 2019: Cochrane Dementia Group Register of Diagnostic Test Accuracy Studies, MEDLINE (OvidSP), Embase (OvidSP), BIOSIS Previews (Web of Knowledge), Science Citation Index (ISI Web of Knowledge), PsycINFO (OvidSP), and LILACS (BIREME). We made no exclusions with regard to language of Mini-Cog administration or language of publication, using translation services where necessary.

SELECTION CRITERIA

We included cross-sectional studies and excluded case-control designs, due to the risk of bias. We selected those studies that included the Mini-Cog as an index test to diagnose dementia where dementia diagnosis was confirmed with reference standard clinical assessment using standardised dementia diagnostic criteria. We only included studies in secondary care settings (including inpatient and outpatient hospital participants).

DATA COLLECTION AND ANALYSIS

We screened all titles and abstracts generated by the electronic database searches. Two review authors independently checked full papers for eligibility and extracted data. We determined quality assessment (risk of bias and applicability) using the QUADAS-2 tool. We extracted data into two-by-two tables to allow calculation of accuracy metrics for individual studies, reporting the sensitivity, specificity, and 95% confidence intervals of these measures, summarising them graphically using forest plots.

MAIN RESULTS

Three studies with a total of 2560 participants fulfilled the inclusion criteria, set in neuropsychology outpatient referrals, outpatients attending a general medicine clinic, and referrals to a memory clinic. Only n = 1415 (55.3%) of participants were included in the analysis to inform evaluation of Mini-Cog test accuracy, due to the selective use of available data by study authors. There were concerns related to high risk of bias with respect to patient selection, and unclear risk of bias and high concerns related to index test conduct and applicability. In all studies, the Mini-Cog was retrospectively derived from historic data sets. No studies included acute general hospital inpatients. The prevalence of dementia ranged from 32.2% to 87.3%. The sensitivities of the Mini-Cog in the individual studies were reported as 0.67 (95% confidence interval (CI) 0.63 to 0.71), 0.60 (95% CI 0.48 to 0.72), and 0.87 (95% CI 0.83 to 0.90). The specificity of the Mini-Cog for each individual study was 0.87 (95% CI 0.81 to 0.92), 0.65 (95% CI 0.57 to 0.73), and 1.00 (95% CI 0.94 to 1.00). We did not perform meta-analysis due to concerns related to risk of bias and heterogeneity.

AUTHORS' CONCLUSIONS

This review identified only a limited number of diagnostic test accuracy studies using Mini-Cog in secondary care settings. Those identified were at high risk of bias related to patient selection and high concerns related to index test conduct and applicability. The evidence was indirect, as all studies evaluated Mini-Cog differently from the review question, where it was anticipated that studies would conduct Mini-Cog and independently but contemporaneously perform a reference standard assessment to diagnose dementia. The pattern of test accuracy varied across the three studies. Future research should evaluate Mini-Cog as a test in itself, rather than derived from other neuropsychological assessments. There is also a need for evaluation of the feasibility of the Mini-Cog for the diagnosis of dementia to help adequately determine its role in the clinical pathway.

Symptom and performance validation in patients with subjective cognitive decline and mild cognitive impairment

Nonauthentic symptom claims (overreporting) and invalid test results (underperformance) can regularly be expected in a forensic context, but may also occur in clinical referrals. While the applicability of symptom and performance validity tests in samples of dementia patients is well studied, the same is not true for patients with subjective cognitive decline (SCD) and mild cognitive impairment (MCI). A sample of 54 memory-clinic outpatients with evidence of SCD or MCI was studied. We evaluated the rate of positive results in three validity measures. A total of 7.4% of the patients showed probable negative response bias in the Word Memory Test. The rate of positive results on the Structured Inventory of Malingered Symptomatology was 14.8% while only one participant (1.9%) scored positive on the Self-Report Symptom Inventory using the standard cutoff. The two questionnaires were moderately correlated at .67. In a combined analysis of all results, five of the patients (9.3%) were judged to show evidence of probable negative response bias (or probably feigned neurocognitive impairment). In the current study, a relatively small but nontrivial rate of probable response distortions was found in a memory-clinic sample. However, it remains a methodological challenge for this kind of research to reliably distinguish between false-positive and correct-positive classifications in clinical patient groups.

Differences regarding the five-factor personality model in patients with subjective cognitive decline and mild cognitive impairment

Personality and dementia are connected in different ways. A broad knowledge about personality and prodromal stages of dementia might be helpful to identify dementia as early as possible. Hence, personality differences between three cognitively impaired groups on the basis of patients’ self-assessments of personality traits and connections between personality and cognitive functioning were examined via a cross-sectional study. The sample consisted of cognitively impaired patients (N = 133), aged 50 and older, who came to a memory clinic due to cognitive complaints. The test procedure encompassed a cognitive screening, the Neuropsychological Test Battery Vienna (NTBV), and self-assessment questionnaires such as the Big Five Plus One Persönlichkeitsinventar (B5PO). While patients with subjective cognitive decline (SCD) did not differ from those with non-amnestic mild cognitive impairment (naMCI) concerning the different personality traits, patients with amnestic mild cognitive impairment (aMCI) showed significantly lower scores for extraversion (p < 0.05), openness (p < 0.001), and empathy (p < 0.001) than patients with SCD as well as patients with naMCI. Thus, cognitively impaired groups mainly differ concerning personality traits depending on whether they do show memory decline or not.

Cortical atrophy pattern-based subtyping predicts prognosis of amnestic MCI: an individual-level analysis

We categorized patients with amnestic mild cognitive impairment (aMCI) based on cortical atrophy patterns and evaluated whether the prognosis differed across the subtypes. Furthermore, we developed a classifier that learns the cortical atrophy pattern and predicts subtypes at an individual level. A total of 662 patients with aMCI were clustered into 3 subtypes based on cortical atrophy patterns. Of these, 467 patients were followed up for more than 12 months, and the median follow-up duration was 43 months. To predict individual-level subtype, we used a machine learning-based classifier with a 10-fold cross-validation scheme. Patients with aMCI were clustered into 3 subtypes: medial temporal atrophy, minimal atrophy (Min), and parietotemporal atrophy (PT) subtypes. The PT subtype had higher prevalence of APOE ε4 carriers, amyloid PET positivity, and greater risk of dementia conversion than the Min subtype. The accuracy for binary classification was 89.3% (MT vs. Rest), 92.6% (PT vs. Rest), and 86.6% (Min vs. Rest). When we used ensemble model of 3 binary classifiers, the accuracy for predicting the aMCI subtype at an individual level was 89.6%. Patients with aMCI with the PT subtype were more likely to have underlying Alzheimer's disease pathology and showed the worst prognosis. Our classifier may be useful for predicting the prognosis of individual aMCI patients.

Individual cognitive change after DBS-surgery in Parkinson's disease patients using Reliable Change Index Methodology

Long-term therapy of Parkinson's disease (PD) with levodopa (L-DOPA) is associated with a high risk of developing motor fluctuations and dyskinesia. Deep brain stimulation (DBS) in PD patients of the subthalamic nucleus can improve these motor complications. Although the positive effect on motor symptoms has been proven, postoperative cognitive decline has been documented. To tackle the impact of PD-DBS on cognition, 18 DBS patients were compared to 25 best medically treated Parkinson's patients, 24 Mild Cognitive Impairment (MCI) patients and 12 healthy controls using the Neuropsychological Test Battery Vienna-long (NTBV-long) for cognitive outcome 12 months after first examination. Reliable change index methodology was used. Overall, there was cognitive change in individual patients, but the change was very heterogeneous with gains and losses. Further research is needed to identify the mechanisms that lead to improvement or deterioration of cognitive functions in individual cases.

Problems in Classifying Mild Cognitive Impairment (MCI): One or Multiple Syndromes?

As the conceptual, methodological, and technological advances applied to dementias have evolved the construct of mild cognitive impairment (MCI), one problem encountered has been its classification into subtypes. Here, we aim to revise the concept of MCI and its subtypes, addressing the problems of classification not only from the psychometric point of view or by using alternative methods, such as latent class analysis, but also considering the absence of normative data. In addition to the well-known influence of certain factors on cognitive function, such as educational level and cultural traits, recent studies highlight the relevance of other factors that may significantly affect the genesis and evolution of MCI: subjective memory complaints, loneliness, social isolation, etc. The present work will contemplate the most relevant attempts to clarify the issue of MCI categorization and classification, combining our own data with that from recent studies which suggest the role of relevant psychosocial factors in MCI.

Semantic memory and depressive symptoms in patients with subjective cognitive decline, mild cognitive impairment, and Alzheimer's disease

BACKGROUND

Semantic memory may be impaired in clinically recognized states of cognitive impairment. We investigated the relationship between semantic memory and depressive symptoms (DS) in patients with cognitive impairment.

METHODS

323 cognitively healthy controls and 848 patients with subjective cognitive decline (SCD), mild cognitive impairment (MCI), and Alzheimer's disease (AD) dementia were included. Semantic knowledge for famous faces, world capitals, and word vocabulary was investigated.

RESULTS

Compared to healthy controls, we found a statistically significant difference of semantic knowledge in the MCI groups and the AD group, respectively. Results of the SCD group were mixed. However, two of the three semantic memory measures (world capitals and word vocabulary) showed a significant association with DS.

CONCLUSIONS

We found a difference in semantic memory performance in MCI and AD as well as an association with DS. Results suggest that the difference in semantic memory is due to a storage loss rather than to a retrieval problem.

Assessment of individual cognitive changes after deep brain stimulation surgery in Parkinson's disease using the Neuropsychological Test Battery Vienna short version

Long-term therapy of Parkinson’s disease with L‑DOPA is associated with a high risk of developing motor fluctuations and dyskinesia. Deep brain stimulation (DBS) of the subthalamic nucleus (STN) can improve these motor complications. Although the positive effect on motor symptoms has been proven, postoperative cognitive decline has been documented. To tackle the impact of DBS on cognition, 18 DBS patients were compared to 25 best medically treated Parkinson’s patients, 24 patients with mild cognitive impairment (MCI) and 12 healthy controls using the Neuropsychological Test Battery Vienna short version (NTBV-short) for cognitive outcome 12 months after the first examination. Reliable change index methodology was used. Roughly 10% of DBS patients showed cognitive decline mainly affecting the domains attention and executive functioning (phonemic fluency). Further research is needed to identify the mechanisms that lead to improvement or deterioration of cognitive functions in individual cases.

Disrupted Odor Perception

Olfactory loss is frequent. However, in public not many people complain of that, or they are even not (fully) aware of it. This indicates that it is possible to live a life without a sense of smell, albeit it is more dangerous, less pleasant, and food tastes much less interesting. Most common causes for smell loss are sinunasal disease (chronic rhinosinusitis with and without nasal polyps), acute infections of the upper airways, head trauma, and neurodegenerative disorders. In many people smell loss seems to be due to the aging process. Before treatment olfactory disorders are diagnosed according to cause with the medical history being a big portion of the diagnostic process. Olfactory disorders are in principle reversible, with a relatively high degree of spontaneous improvement in olfactory loss following infections of the upper respiratory tract. Medical treatment is according to cause. It also involves surgical approaches as well as conservative treatments including the use of corticosteroids, antibiotics, or smell training. Because today olfactory dysfunction seems to receive more attention than in previous years it can be expected that tomorrow we will have more specific and effective treatment options available.

The impact of depressive symptoms on health-related quality of life in patients with subjective cognitive decline, mild cognitive impairment, and Alzheimer's disease

BACKGROUND

Health-related quality of life (HRQOL) is an important issue in the context of dementia care. The purpose of this study was to investigate the association between HRQOL and depressive symptoms in patients with subjective cognitive decline (SCD) and subtypes of mild cognitive impairment (MCI) and Alzheimer´s disease (AD).

METHODS

In this cross-sectional, observational study, a control group and four experimental groups (SCD, non-amnestic MCI, amnesticMCI, AD) were compared. Neuropsychological measurers (NTBV) and psychological questionnaires were used for data collection.

RESULTS

The control group scored higher than patients with SCD, naMCI, aMCI, or AD for the Mental Health Component Score (MHCS) of the Short Form of the Health Survey (SF-36). The Physical Health Component Score (PHCS) of the SF-36 differed only between some groups. Furthermore, cognitive variables were more strongly associated with the physical aspects of HRQOL, whereas depressive symptoms were more strongly related with the mental aspects of HRQOL.

CONCLUSIONS

HRQOL and depressive symptoms are closely related in patients with cognitive impairments. Therefore, it is of great importance to assess patients with subjective impairment carefully in terms of depressive symptoms.

Activities of Daily Living and Depressive Symptoms in Patients with Subjective Cognitive Decline, Mild Cognitive Impairment, and Alzheimer's Disease

BACKGROUND

Subjective cognitive decline (SCD) may be an early indicator for an increased risk of dementia. The exact definition of SCD remains unclear and has recently become a major research interest.

OBJECTIVES

To determine impairments in activities of daily living (ADL) and depressive symptoms in elderly individuals with SCD, mild cognitive impairment (MCI), and Alzheimer's disease (AD).

METHODS

We included 752 consecutive patients suffering from SCD, non-amnestic (naMCI) or amnestic MCI (aMCI), AD, and 343 healthy controls into this prospective cohort study. A neuropsychological test battery, B-ADL and BDI-II was performed.

RESULTS

SCD patients showed a decreased performance in ADL compared to controls. Performance in ADL declined concurrently with cognitive abilities along the controls-SCD-naMCI-aMCI-AD continuum. Individuals with cognitive complains, no matter if SCD, MCI, or AD patients, reported more often depressive symptoms compared to healthy controls without complaints. Within all five cognitive subgroups, patients with depressive symptoms reported more difficulties in ADL in comparison to patients without depressive symptoms. Adjusting for depressive symptoms, there was no significant group difference between the control versus the SCD group (OR 1.1, CI 0.6-1.7).

CONCLUSIONS

SCD is a heterogeneous clinical condition. Specific features such as slightly impaired ADL and depressive symptoms are associated with SCD. Clinical markers may serve as an indicator for preclinical AD and in combination with biomarkers guide to an early diagnosis of a progressive neurodegenerative disease.

Health-Related Quality of Life in Patients with Subjective Cognitive Decline and Mild Cognitive Impairment and its Relation to Activities of Daily Living

BACKGROUND

Health related quality of life (HRQOL) is an important issue in the context of dementia care.

OBJECTIVES

The purpose of this study was to investigate HRQOL in patients with subjective cognitive decline (SCD) and mild cognitive impairment (MCI) and its relation to Activity of Daily Living (ADL).

METHODS

In this cross sectional study, four experimental groups (each n = 98), controls, SCD, naMCI and aMCI, were compared. For data collection, neuropsychological methods (NTBV) and psychological questionnaires (SF-36 and B-ADL) were used. Multivariate analysis of variance was calculated to detect differences in HRQOL between groups. Correlations between HRQOL and ADL were explored.

RESULTS

The dimensions of HRQOL showed mainly consistent differences between the control and the SCD group and MCI subgroups. In almost every dimension of HRQOL, the control group scored higher than subjects with SCD, naMCI, or aMCI. The controls showed low to moderate negative correlations between HQROL and B-ADL in some dimensions of the HRQOL. In the SCD group, low negative correlations with ADL were observed in some HRQOL scales. Low to moderate correlations were found between each scale of the SF-36 and the B-ADL in both MCI subtypes. We found gender differences in HRQOL.

CONCLUSION

In conclusion, we could demonstrate that patients with SCD report reduced quality of life. This knowledge is important to get a better understanding of the individuals with SCD and may pave the way for the development of early intervention.

Facial emotion recognition and its relationship to cognition and depressive symptoms in patients with Parkinson's disease

BACKGROUND

Impairments in facial emotion recognition (FER) have been detected in patients with Parkinson disease (PD). Presently, we aim at assessing differences in emotion recognition performance in PD patient groups with and without mild forms of cognitive impairment (MCI) compared to healthy controls.

METHODS

Performance on a concise emotion recognition test battery (VERT-K) of three groups of 97 PD patients was compared with an age-equivalent sample of 168 healthy controls. Patients were categorized into groups according to two well-established classifications of MCI according to Petersen's (cognitively intact vs. amnestic MCI, aMCI, vs. non-amnestic MCI, non-aMCI) and Litvan's (cognitively intact vs. single-domain MCI, sMCI, vs. multi-domain MCI, mMCI) criteria. Patients and controls underwent individual assessments using a comprehensive neuropsychological test battery examining attention, executive functioning, language, and memory (Neuropsychological Test Battery Vienna, NTBV), the Beck Depression Inventory, and a measure of premorbid IQ (WST).

RESULTS

Cognitively intact PD patients and patients with MCI in PD (PD-MCI) showed significantly worse emotion recognition performance when compared to healthy controls. Between-groups effect sizes were substantial, showing non-trivial effects in all comparisons (Cohen's ds from 0.31 to 1.22). Moreover, emotion recognition performance was higher in women, positively associated with premorbid IQ and negatively associated with age. Depressive symptoms were not related to FER.

CONCLUSIONS

The present investigation yields further evidence for impaired FER in PD. Interestingly, our data suggest FER deficits even in cognitively intact PD patients indicating FER dysfunction prior to the development of overt cognitive dysfunction. Age showed a negative association whereas IQ showed a positive association with FER.

Subjective Memory Complaints and Conversion to Dementia in Patients with Subjective Cognitive Decline and Patients with Mild Cognitive Impairment

Abstract. Background: Subjective cognitive complaints and their clinical significance are discussed controversially. Objectives: To determine the clinical validity of subjective cognitive complaints among subjects with subjective cognitive decline (SCD) and mild cognitive impairment (MCI). Design: Longitudinal study with one follow up examination at a University based out-patient memory clinic. Participants: A clinical sample of patietns with SCD and MCI (n = 141), aged 50 and older, who came to the memory outpatient clinic. Results: No significant differences between converters and non converters regarding subjective cognitive complaints were detected. MCI patients had a higher risk than the patients with SCD developing AD (OR = 7.3 [CI 0.9 to 61.2]. Verbal memory testing using the Verbal Selektive Reminding Test (VSRT) showed better diagnostic validity than subjective cognitive complaints using the Forgetfulness Assessment Inventory (FAI) in predicting conversion to dementia. Conclusion: Verbal memory testing was superior in predicting conversion to dementia compared to subjective cognitive complaints.

Facial emotion recognition in patients with subjective cognitive decline and mild cognitive impairment

BACKGROUND

Deficits in facial emotion recognition (FER) have been shown to substantially impair several aspects in everyday life of affected individuals (e.g. social functioning). Presently, we aim at assessing differences in emotion recognition performance in three patient groups suffering from mild forms of cognitive impairment compared to healthy controls.

METHODS

Performance on a concise emotion recognition test battery (VERT-K) of 68 patients with subjective cognitive decline (SCD), 44 non-amnestic (non-aMCI), and 25 amnestic patients (aMCI) with mild cognitive impairment (MCI) was compared with an age-equivalent sample of 138 healthy controls all of which were recruited within the framework of the Vienna Conversion to Dementia Study. Additionally, patients and controls underwent individual assessment using a comprehensive neuropsychological test battery examining attention, executive functioning, language, and memory (NTBV), the Beck Depression Inventory (BDI), and a measure of premorbid IQ (WST).

RESULTS

Type of diagnosis showed a significant effect on emotion recognition performance, indicating progressively deteriorating results as severity of diagnosis increased. Between-groups effect sizes were substantial, showing non-trivial effects in all comparisons (Cohen's ds from -0.30 to -0.83) except for SCD versus controls. Moreover, emotion recognition performance was higher in women and positively associated with premorbid IQ.

CONCLUSIONS

Our findings indicate substantial effects of progressive neurological damage on emotion recognition in patients. Importantly, emotion recognition deficits were observable in non-amnestic patients as well, thus conceivably suggesting associations between decreased recognition performance and global cognitive decline. Premorbid IQ appears to act as protective factor yielding lesser deficits in patients showing higher IQs.

Associations Between Mild Cognitive Impairment and Hospitalization and Readmission

OBJECTIVES

To determine whether older adults with mild cognitive impairment (MCI), a condition not previously explored as a risk factor, have more hospitalizations and 30-day readmissions than those with normal cognition.

DESIGN

Post hoc analysis of prospectively gathered data on incident hospitalization and readmission from the Ginkgo Evaluation of Memory Study (GEMS), a randomized, double-blind, placebo-controlled trial designed to assess the effect of Ginkgo biloba on incidence of dementia.

SETTING

GEMS was conducted in five academic medical centers in the United States.

PARTICIPANTS

Community-dwelling adults aged 75 and older with normal cognition (n = 2,314) or MCI (n = 428) at baseline cognitive testing (N = 2,742).

MEASUREMENTS

Index hospitalization and 30-day hospital readmission, adjusted for age, sex, race, education, clinic site, trial assignment status, comorbidities, number of prescription medications, and living with an identified proxy.

RESULTS

MCI was associated with a 17% greater risk of index hospitalization than normal cognition (adjusted hazard ratio (aHR) = 1.17, 95% confidence interval (CI) = 1.02-1.34)). In participants who lived with a proxy, MCI was associated with a 39% greater risk of index hospitalization (aHR = 1.39, 95% CI = 1.17-1.66). Baseline MCI was not associated with greater odds of 30-day hospital readmission (adjusted odds ratio = 0.90, 95% CI = 0.60-1.36).

CONCLUSION

MCI may represent a target condition for healthcare providers to coordinate support services in an effort to reduce hospitalization and subsequent disability.

Depressive Symptoms are the Main Predictor for Subjective Sleep Quality in Patients with Mild Cognitive Impairment--A Controlled Study

Objective

Controlled data on predictors of subjective sleep quality in patients with memory complaints are sparse. To improve the amount of comprehensive data on this topic, we assessed factors associated with subjective sleep quality in patients from our memory clinic and healthy individuals.

Methods

Between February 2012 and August 2014 patients with mild cognitive impairment (MCI) and subjective cognitive decline (SCD) from our memory clinic and healthy controls were recruited. Apart from a detailed neuropsychological assessment, the subjective sleep quality, daytime sleepiness and depressive symptoms were assessed using the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS) and the Beck Depression Inventory (BDI-II).

Results

One hundred fifty eight consecutive patients (132 (84%) MCI patients and 26 (16%) SCD patients) and 75 healthy controls were included in the study. Pairwise comparison of PSQI scores showed that non-amnestic MCI (naMCI) patients (5.4±3.5) had significantly higher PSQI scores than controls (4.3±2.8, p = .003) Pairwise comparison of PSQI subscores showed that naMCI patients (1.1±0.4) had significantly more “sleep disturbances” than controls (0.9±0.5, p=.003). Amnestic MCI (aMCI) (0.8±1.2, p = .006) and naMCI patients (0.7±1.2, p = .002) used “sleep medication” significantly more often than controls (0.1±0.6) Both, aMCI (11.5±8.6, p<.001) and naMCI (11.5±8.6, p<.001) patients showed significantly higher BDI-II scores than healthy controls (6.1±5.3). Linear regression analysis showed that the subjective sleep quality was predicted by depressive symptoms in aMCI (p<.0001) and naMCI (p<.0001) patients as well as controls (p<.0001). This means, that more depressive symptoms worsened subjective sleep quality. In aMCI patients we also found a significant interaction between depressive symptoms and global cognitive function (p = .002)

Discussion

Depressive symptoms were the main predictor of subjective sleep quality in MCI patients and controls, but not in SCD patients. Better global cognitive function ameliorated the negative effect of depressive symptoms on the subjective sleep quality in aMCI patients.

Visuo-constructional functions in patients with mild cognitive impairment, Alzheimer's disease, and Parkinson's disease

BACKGROUND

Several recently proposed criteria for assessing cognitive disorder require measuring the cognitive domain of visuo-constructional function. The aims of the present study were to develop a new test (Vienna Visuo-constructional Test-VVT) measuring visuo-constructional functions and to determine the reliability and validity of the VVT in patients with mild cognitive impairment (MCI), Parkinson's disease (PD), and Alzheimer's disease (AD). We further examined age and sex effects and the psychometric quality of the VVT.

METHODS

The study included 76 healthy controls and 103 patients who were referred to the Department of Neurology, Medical University of Vienna for neurocognitive assessment. An administering and scoring system for the VVT was developed.

RESULTS

Internal consistency (Cronbach's alpha) was found to range from 0.82 for the healthy control group to 0.93 for the total patient group. There was no sex effect, but age had a negative effect on VVT performance. The VVT successfully differentiated healthy controls from MCI patients, AD patients, and PD patients, respectively.

CONCLUSION

The VVT shows satisfactory validity and reliability and can be administered easily in clinical practice. It constitutes a new measure that can successfully be used to identify visuo-constructional problems in patients with cognitive dysfunction.

Awareness of memory deficits in subjective cognitive decline, mild cognitive impairment, Alzheimer's disease and Parkinson's disease

BACKGROUND

Impaired awareness of memory deficits has been recognized as a common phenomenon in Alzheimer's disease (AD) and research is now increasingly focusing on awareness in groups at risk for future dementia. This study aimed to determine whether levels of awareness differ among healthy elderly people and patients with subjective cognitive decline (SCD), amnestic and non-amnestic subtypes of mild cognitive impairment (aMCI, naMCI), Alzheimer's disease (AD) and Parkinson's disease (PD), to explore correlates of awareness and to establish frequencies of memory over- and underestimation within each diagnostic group.

METHODS

756 consecutive outpatients of a memory clinic and 211 healthy controls underwent thorough neuropsychological testing. Impairment of awareness was measured as the difference between subjective memory appraisals (16-item questionnaire on current memory-related problems in everyday life) and objective memory performance (15-item delayed recall task). Subgroups of over- and underestimators were classified using percentile ranks of controls.

RESULTS

At group level, awareness significantly decreased along the naMCI→aMCI→AD continuum, with naMCI patients showing a tendency towards overestimation of memory dysfunction. PD patients showed accurate self-appraisals as long as memory function was largely unaffected. However, there was a considerable between-group overlap in awareness scores. Furthermore, different correlates of awareness were observed depending on the diagnostic group. In general, unawareness seems to be associated with decreased cognitive performance in various domains (especially memory), higher age and lower levels of depression and self-reported functional impairment.

CONCLUSION

Impaired awareness is an important symptom in aMCI. Yet, given the considerable variability in awareness scores, longitudinal studies are required to evaluate their predictive power.

Assessing the utility of the Movement Disorder Society Task Force Level 1 diagnostic criteria for mild cognitive impairment in Parkinson's disease

BACKGROUND

Using the Movement Disorder Society (MDS) Task Force Level 1 criteria, this study examined the classification of mild cognitive impairment in Parkinson's Disease (PD-MCI) derived from a range of cut-off scores that have previously been suggested by the MDS Task Force. Furthermore, differences in PD-MCI frequencies were examined when comparing performance on current neuropsychological testing to the normative sample, as opposed to decline from premorbid functioning, as evidence of cognitive impairment.

METHOD

Two hundred and thirty-four non-demented PD patients underwent neurological and neuropsychological assessment at the Parkinson's Disease Research Clinic at the Brain and Mind Research Institute, University of Sydney.

RESULTS

When cognitive impairment was defined as 1SD and 1.5SD below premorbid intellect, 109 patients (47%) and 76 (32%) patients met criteria for PD-MCI respectively. This proportion dropped considerably to 50 patients (21%) with a 2SD cut-off score. However, when calculating impairment based on comparisons with normative data, only 68 patients (29%) and 41 patients (18%) met PD-MCI criteria when a cut-off score of 1 and 1.5SD was employed. This proportion dropped to just 22 patients (9%) with a 2SD cut-off score.

CONCLUSION

Results from the present study suggest that the MDS PD-MCI criteria may be too broad, as substantial differences in frequencies of PD-MCI were observed with the application of differing criteria. We propose that a 1.5SD cut-off score below premorbid functioning may provide greater utility in characterizing PD-MCI than a 1.5SD cut-off below normative data, which has been widely applied in previous studies examining the MDS PD-MCI criteria.

Patients with mild cognitive impairment have an abnormal upper-alpha event-related desynchronization/synchronization (ERD/ERS) during a task of temporal attention

There are several evidences indicating that an impairment in attention-executive functions is present in prodromal Alzheimer's disease and predict future global cognitive decline. In particular, the issue of temporal orienting of attention in patients with mild cognitive impairment (MCI) due to Alzheimer's disease has been overlooked. The present research aimed to explore whether subtle deficits of cortical activation are present in these patients early in the course of the disease. We studied the upper-alpha event-related synchronization/desynchronization phenomenon during a paradigm of temporal orientation of attention. MCI patients (n = 27) and healthy elderly controls (n = 15) performed a task in which periodically omitted tones had to be predicted and their virtual onset time had to be marked by pressing a button. Single-trial responses were measured, respectively, before and after the motor response. Then, upper-alpha responses were compared to upper-alpha power during eyes-closed resting state. The time course of the task was characterized by two different behavioral conditions: (1) a pre-event epoch, in which the subject awaited the virtual onset of the omitted tone, (2) a post-event epoch (after button pressing), in which the subject was in a post-motor response condition. The principal findings are: (1) during the waiting epoch, only healthy elderly had an upper-alpha ERD at the level of both temporal and posterior brain regions; (2) during the post-motor epoch, the aMCI patients had a weaker upper-alpha ERS on prefrontal regions; (3) only healthy elderly showed a laterality effect: (a) during the waiting epoch, the upper-alpha ERD was greater at the level of the right posterior-temporal lead; during the post-motor epoch, the upper alpha ERS was greater on the left prefrontal lead. The relevance of these findings is that the weaker upper-alpha response observed in aMCI patients is evident even if the accuracy of the behavioral performance (i.e., button pressing) is still spared. This abnormal upper-alpha response might represent an early biomarker of the attention-executive network impairment in MCI due to Alzheimer's disease.

Subjective memory complaints, depressive symptoms and cognition in Parkinson's disease patients

BACKGROUND AND PURPOSE

The goal of this study was to establish the prevalence of subjective memory complaints (SMCs) and depressive symptoms (DS)s and their relation to cognitive functioning in patients with Parkinson's disease (PD).

METHODS

In all, 248 controls and 104 PD patients were included in the study. The PD group was subdivided into three PD subtypes with mild cognitive impairment (MCI) according to the Petersen criteria and three PD subtypes with MCI according to the Litvan criteria.

RESULTS

Substantial SMCs were reported by 7.7% of controls and 16.3% of the PD patients (P < 0.001). A clinically relevant degree of DSs was evident in 16.6% of controls compared with 40.4% in the PD group (P < 0.001). An analysis of variance revealed a statistically significant difference for SMCs across all Petersen groups as well across all Litvan groups. Two-factor analyses of variance with the factors cognitive status (MCI subtype) and depressive state (depressed versus not depressed) and SMCs as dependent variable revealed significant results.

CONCLUSIONS

Approximately 15% of PD patients seeking help in a movement disorder clinic report significant SMCs, with an increasing degree from cognitively healthy PD to PD-MCI. Significant DSs increase SMCs across all cognitive status groups.

Subjective memory complaints, depressive symptoms and cognition in patients attending a memory outpatient clinic

BACKGROUND

The goals of this study were to establish prevalence of subjective memory complaints (SMC) and depressive symptoms (DS) and their relation to cognitive functioning and cognitive status in an outpatient memory clinic cohort.

METHODS

Two hundred forty-eight cognitively healthy controls and 581 consecutive patients with cognitive complaints who fulfilled the inclusion criteria were included in the study.

RESULTS

A statistically significant difference (p < 0.001) between control group and patient group regarding mean SMC was detected. 7.7% of controls reported a considerable degree of SMC, whereas 35.8% of patients reported considerable SMC. Additionally, a statistically significant difference (p < 0.001) between controls and patient group regarding Beck depression score was detected. 16.6% of controls showed a clinical relevant degree of DS, whereas 48.5% of patients showed DS. An analysis of variance revealed a statistically significant difference across all four groups (control group, SCI group, naMCI group, aMCI group) (p < 0.001). Whereas 8% of controls reported a considerable degree of SMC, 34% of the SCI group, 31% of the naMCI group, and 54% of the aMCI group reported considerable SMC. A two-factor analysis of variance with the factors cognitive status (controls, SCI group, naMCI group, aMCI group) and depressive status (depressed vs. not depressed) and SMC as dependent variable revealed that both factors were significant (p < 0.001), whereas the interaction was not (p = 0.820).

CONCLUSIONS

A large proportion of patients seeking help in a memory outpatient clinic report considerable SMC, with an increasing degree from cognitively healthy elderly to aMCI. Depressive status increases SMC consistently across groups with different cognitive status.

Prevalence of Mild Cognitive Impairment Subtypes in Patients with Parkinson’s Disease – Comparison of two Modes of Classification

Early detection of dementia in Parkinson’s disease is becoming increasingly important. The goal of this study was to establish prevalence of mild cognitive impairment subtypes in Parkinson’s disease using two different modes of mild cognitive impairment classification. Categorizing patients into mild cognitive impairment subtypes according to the minimum mode of mild cognitive impairment classification revealed the following results: three patients (2.5 %) were categorized as cognitively healthy, whereas 117 patients (97.5 %) met the criteria for mild cognitive impairment. When categorizing patients according to the mean mode of mild cognitive impairment classification, 41.7 % of the patients were categorized as cognitively healthy, whereas 58.3 % met the criteria for mild cognitive impairment. Frequency of mild cognitive impairment varies substantially, depending on how impairment is defined.