Assessing cognitive insight in nonpsychiatric individuals and outpatients with schizophrenia in Taiwan: an investigation using the Beck Cognitive Insight Scale

<p>Abstract</p> <p>Background</p> <p>The Beck Cognitive Insight Scale (BCIS) was designed for the assessment of the cognitive processes involved in self-reflection and the ability to modify erroneous beliefs and misinterpretations. Studies investigating the factor structure of the BCIS have indicated a two-factor model in the psychotic population. The factor structure of the BCIS, however, has not received much consideration in the nonpsychiatric population. The present study examined the factor structure and validity of the BCIS and compared its scores between nonpsychiatric individuals and outpatients with psychosis.</p> <p>Method</p> <p>The Taiwanese version of the BCIS was administered to 507 nonpsychiatric individuals and 118 outpatients with schizophrenia. The psychometric properties of the BCIS were examined through the following analyses: exploratory and confirmatory factor analyses, reliability, correlation analyses, and discriminative validity.</p> <p>Results</p> <p>The BCIS showed adequate internal consistency and stability over time. Exploratory and confirmatory factor analyses on the 15-item measure indicated a two-factor solution that supported the two dimensions of the Taiwanese BCIS, which was also observed with the original BCIS. Following the construct validation, we obtained a composite index (self-reflectiveness minus self-certainty) of the Taiwanese BCIS that reflected cognitive insight. Consistent with previous studies, our results indicated that psychosis is associated with low self-reflectiveness and high self-certainty, which possibly reflect lower cognitive insight. Our results also showed that better cognitive insight is related to worse depression in patients with schizophrenia spectrum disorders, but not in nonpsychiatric individuals. The receiver operating characteristic (ROC) analyses revealed that the area under the curve (AUC) was 0.731. A composite index of 3 was a good limit, with a sensitivity of 87% and a specificity of 51%.</p> <p>Conclusion</p> <p>The BCIS proved to be useful for measuring cognitive insight in Taiwanese nonpsychiatric and psychotic populations.</p

Genetically elevated high-density lipoprotein cholesterol through the cholesteryl ester transfer protein gene does not associate with risk of Alzheimer's disease

Introduction: There is conflicting evidence whether high-density lipoprotein cholesterol (HDL-C) is a risk factor for Alzheimer's disease (AD) and dementia. Genetic variation in the cholesteryl ester transfer protein (CETP) locus is associated with altered HDL-C. We aimed to assess AD risk by genetically predicted HDL-C. Methods: Ten single nucleotide polymorphisms within the CETP locus predicting HDL-C were applied to the International Genomics of Alzheimer's Project (IGAP) exome chip stage 1 results in up 16,097 late onset AD cases and 18,077 cognitively normal elderly controls. We performed instrumental variables analysis using inverse variance weighting, weighted median, and MR-Egger. Results: Based on 10 single nucleotide polymorphisms distinctly predicting HDL-C in the CETP locus, we found that HDL-C was not associated with risk of AD (P > .7). Discussion: Our study does not support the role of HDL-C on risk of AD through HDL-C altered by CETP. This study does not rule out other mechanisms by which HDL-C affects risk of AD

Self-awareness in Mild Cognitive Impairment: Quantitative evidence from systematic review and meta-analysis

Here we quantitatively summarized evidence of impaired awareness in Mild Cognitive Impairment (MCI) and meta-analytically explored the relationship between Subjective Cognitive Complaints (SCC) and actual cognitive impairment. Twenty-three studies were included, 14 comparing awareness measures in MCI and healthy elderly subjects, and 16 also exploring the neuropsychological underpinnings of impaired awareness. Moderator analyses were conducted to determine whether self-awareness varied according to patient group, the particular state in relation to which insight was assessed, or the approach to measuring awareness. The meta-analysis shows that MCI patients have knowledge of their neuropsychological deficits and that level of awareness varies according to cognitive status, language and memory abilities. The assessment technique employed impacted on the insight phenomena. Specifically, MCI patients seem particularly accurate in evaluating the current state of their performance during an ongoing task and this could be essential in regulating their behavior so that compensative strategies are practiced and greater cognitive independence is achieved. Thus, assessment technique and cognitive status are crucial factors that influence level of awareness and should be taken into consideration in awareness evaluation and rehabilitation

Inverse effect of the APOE epsilon4 allele in late- and early-onset Alzheimer’s disease

In Alzheimer's disease patients (AD), the age at onset (AAO) ranges from 40 to 90. Usually, AD patients who develop symptoms before the age of 65 are classified as early onset (EO). The best known genetic risk factor for AD is the ε4 allele of the apolipoprotein E (APOE). In this study, 474 subjects with AD were consecutively recruited in the memory clinic of the Santa Lucia Foundation in Rome. The best fitting model  for the discrimination between EO and late onset (LO) was chosen based on lowest value of the Bayesian Information Criterion, which suggests the theoretical model with minimal deviation from the empirical distribution function of AAO in our sample. The FMM was used to compare EO and LO groups with respect to the following demographic and clinical variables: gender, age, education, MMSE and NPI. Furthermore a quantitative assessment of ADL and IADL was performed. Finally, the frequency of the APOE ε4 allele was compared in EO and LO groups. Using the admixture analysis, we established that the AAO discriminating EO from LO-AD was 63-64. Higher education was associated with earlier onset in the EO but not in LO, and duration of illness was associated with earlier onset only in LO. The ε4 allele was associated with later onset in EO but earlier onset in LO. Finally, increased impairment in ADL, IADL and NPI was associated with later onset only in the LO subgroup. Thus, the ε4 allele of the APOE gene was significantly associated with both EO and LO distributions but with opposite effect, suggesting genetic heterogeneity. Additional studies are needed to further clarify the genetic mechanisms differentiating EO- and LO-AD

Alexithymia in Parkinson's disease: A systematic review of the literature

In this systematic review, we aimed to evaluate the role of alexithymia in Parkinson's disease (PD) and its relationship to neurological, neuropsychiatric, cognitive, and neuroimaging correlates

Atrophy of presubiculum and subiculum is the earliest hippocampal anatomical marker of Alzheimer's disease

BACKGROUND: There is no consensus about which hippocampal subfields become atrophic earliest in the course of Alzheimer's disease (AD). METHODS: Thirty AD patients, 41 mild cognitive impairment (MCI) patients, and 38 healthy controls (HCs) underwent cerebral magnetic resonance imaging (with an automated segmentation protocol for the volumetric analysis of hippocampal subfields) and a test of immediate and delayed recall of a 15-word list. RESULTS: The volumes of the presubiculum and subiculum presented the most remarkable reduction in the patient's groups. In the MCI group, only the volumes of presubiculum and subiculum predicted performance on the memory tests. In AD patients, the volumes of all hippocampal subfields (with the notable exception of the CA1) predicted memory scores. CONCLUSIONS: Our data point to a prevalent atrophy of the presubicular-subicular complex from the early phases of AD. This finding is consistent with neuropathological observations in AD patients and probably reflects the severe degeneration of the perforant pathway while penetrating the hippocampus through the subicular field in its course from the entorhinal cortex to the dentate gyrus.

Longitudinal Neuropsychiatric Predictors of Death in Alzheimer's Disease

Characteristics associated with life expectancy in Alzheimer's disease (AD) are still far from known. Here we aimed at examining the ability of baseline/longitudinal clinical variables to predict time to death. One-hundred fifty AD outpatients underwent diagnostic, neuropsychiatric, and functional assessment at baseline (when ApoE ɛ4 was also investigated) and at each subsequent annual visit. A random effects joint modeling approach was used to simultaneously model the baseline and longitudinal trajectory of each factor and predict the time to death, adjusting for demographic covariates. An ancillary analysis of ApoE ɛ4 status as a predictor was also conducted. Kaplan-Meier survival curves were constructed to elucidate the relationship between each factor and the estimated probability of death over time. Shorter survival was associated with male gender, higher education, older age, lower cognition, and worse functioning in daily life, but not ApoE ɛ4 status. Longitudinal trajectories increased predictive power over using just baseline levels highlighting apathy, and secondarily aberrant motor behaviors and sleep disorders, as a highly reliable predictor for mortality. Apathy was the strongest neuropsychiatric predictor of time to death, which supports its role in the pathogenesis of the disorder. An increased knowledge of factors modulating survival in AD is a strategic prerequisite to plan therapeutic interventions

Myeloid dendritic cells are decreased in peripheral blood of Alzheimer's disease patients in association with disease progression and severity of depressive symptoms

Dendritic cells (DCs) are major orchestrators of immune responses and inflammation. They are migratory cells, which may play a role in Alzheimer's disease (AD), as suggested by prior in vitro studies. With the intent to investigate the clinical relevance of DC modifications in vivo, the present study was aimed to evaluate the levels of blood DCs in AD patients, in relation to the progression of the disease, the severity of its symptoms, and the treatment with acetylcholinesterase inhibitors (AChEIs), a class of drugs used to improve cognitive functioning in people with dementia

Corpus callosum structure is topographically correlated with the early course of cognition and depression in Alzheimer's disease

Corpus callosum (CC) abnormalities may cause cognitive and neuropsychiatric complications due to reduced hemispheric integration. Over a one-year period, we investigated whether the CC structure of 20 patients with mild Alzheimer's disease (AD) was linked to the evolution of cognitive and neuropsychiatric symptoms. We also investigated whether this anatomical-clinical relationship was localized topographically on the CC by combining voxel-based morphometry and diffusion tensor imaging approaches. We assessed patients' global cognitive deterioration and neuropsychiatric symptoms with the Mini-Mental State Examination and the Neuropsychiatric Inventory. Increased global cognitive deterioration during the early course of AD was significantly related to reduced white matter density (p = 0.004) and fractional anisotropy (FA) (p = 0.012) and increased mean diffusivity (MD) (p = 0.017) at the level of the CC isthmus/splenium. Further, increased depression severity was significantly related to reduced FA (p = 0.008) and increased MD (p = 0.018) at the level of the CC rostrum. These results indicate that changes in early myelinated CC fibers, which subserve the lateral temporal and parietal cortices and are less vulnerable to damage, may be related to cognitive impairment. Furthermore, changes in late myelinated CC fibers, which connect the orbitofrontal cortices and are more vulnerable to damage, may be related to the earliest neuropsychiatric symptoms of AD, such as depression