Evaluation of Incidence and Clinical Features of Antibody-Associated Autoimmune Encephalitis Mimicking Dementia

Background. Anti-neuronal autoimmunity may cause cognitive impairment that meets the criteria for dementia. Objective. Our aim was to detect the incidence and clinical features of autoimmune encephalitis imitating clinical findings of primary dementia disorders and to delineate the validity of anti-neuronal antibody screening in dementia patients. Methods. Fifty consecutive patients fulfilling the clinical criteria for primary dementia, 130 control patients, and 50 healthy controls were included. Their sera were investigated for several ion channel and glutamic acid decarboxylase (GAD) antibodies by a cell-based assay, radioimmunoassay, and ELISA, as required. Results. Sixteen patients satisfying dementia criteria had atypical findings or findings suggestive of autoimmune encephalitis. N-methyl-D-aspartate receptor (NMDAR) antibody was detected in a patient with dementia, Parkinsonism, and REM sleep behavior disorder (RBD) fulfilling the criteria for dementia with Lewy bodies (DLB). One control patient with bipolar disease displayed low anti-GAD antibody levels. Conclusions. Our study showed for the first time the presence of parkinsonism and RBD in an anti-NMDAR encephalitis patient mimicking DLB. Although autoimmune encephalitis patients may occasionally present with cognitive decline, most dementia patients do not exhibit anti-neuronal antibodies, suggesting that routine analysis of these antibodies in dementia is not mandatory, even though they display atypical features

Rey Complex Figure Test and Recognition Trial (RCFT): Norm Determination Study on Turkish Adult Sample

OBJECTIVE: Scientific BACKGROUND: Rey Complex Figure Test and Recognition Trial (RCFT) is a commonly used neuropsychological measure which assesses visuoconstructive skills and non-verbal memory. OBJECTIVE: The purpose of this study was to provide normative data for Turkish adults and investigate the influence of age, education and gender variables on the RCFT performance METHODS: MATERIAL-METHODS: Data derived from a sample of 198 healthy individuals (age 17-82) coming from six different age and three different education levels. RESULTS: RESULTS: This study revealed significant effects of age and education on most of the RCFT test scores. It also revealed that RCFT performances were not associated with gender. CONCLUSION: CONCLUSION: The evaluation criterias for the RCFT scores, which could be used in the clinical trials in our country, is determined with this stud

Implicit Contextual Learning in Spinocerebellar Ataxia

Objective: Cerebellum is traditionally associated with motor functions, but recently its functions were broadened to include cognitive and affective functions as well. The impairment of these nonmotor functions was subsumed under the term cerebellar cognitive-affective syndrome (CCAS). Spinocerebellar ataxias (SCAs) are a family of hereditary degeneration, which is associated with progressive atrophy of the cerebellum. This study aimed to examine the cerebellar contribution to nonmotor implicit learning, which is the ability to acquire visual contextual information via repeated spatial configurations from the environment without conscious awareness in patients with SCA. Method: Twenty patients with SCA and matched healthy controls performed implicit contextual learning task that is a nonmotor. implicit, visual learning task consisting displays of a target (letter 1) and a number of distractors (letter L). Results: We found implicit contextual learning impairment vis-a-vis spared visuomotor skill learning in SCA. Moreover, this impairment did not correlate with any other measure, including demographics. clinical measures. and neuropsychological measures. Conclusion: These findings broaden the role of cerebellum in nonmotor. implicit, spatial learning processes

Screening for preclinical Alzheimer’s disease: Deriving optimal policies using a partially observable Markov model

Alzheimer’s Disease (AD) is believed to be the most common type of dementia. Even though screening for AD has been discussed widely, there is no screening program implemented as part of a policy in any country. Current medical research motivates focusing on the preclinical stages of the disease in a modeling initiative. We develop a partially observable Markov decision process model to determine optimal screening programs. The model contains disease free and preclinical AD partially observable states and the screening decision is taken while an individual is in one of those states. An observable diagnosed preclinical AD state is integrated along with observable mild cognitive impairment, AD and death states. Transition probabilities among states are estimated using data from Knight Alzheimer’s Disease Research Center (KADRC) and relevant literature. With an objective of maximizing expected total quality-adjusted life years (QALYs), the output of the model is an optimal screening program that specifies at what points in time an individual over 50 years of age with a given risk of AD will be directed to undergo screening. The screening test used to diagnose preclinical AD has a positive disutility, is imperfect and its sensitivity and specificity are estimated using the KADRC data set. We study the impact of a potential intervention with a parameterized effectiveness and disutility on model outcomes for three different risk profiles (low, medium and high). When intervention effectiveness and disutility are at their best, the optimal screening policy is to screen every year between ages 50 and 95, with an overall QALY gain of 0.94, 1.9 and 2.9 for low, medium and high risk profiles, respectively. As intervention effectiveness diminishes and/or its disutility increases, the optimal policy changes to sporadic screening and then to never screening. Under several scenarios, some screening within the time horizon is optimal from a QALY perspective. Moreover, an in-depth analysis of costs reveals that implementing these policies are either cost-saving or cost-effective

Affective theory of mind in human aging: is there any relation with executive functioning?

PubMed ID: 30994403Theory of Mind (ToM) refers to the ability to make inferences on other’s mental or emotional states. Although there is evidence suggesting that impaired executive functions due to aging could have a negative impact on cognitive ToM, there is still controversy about the effect of age and age-related executive dysfunctions on affective ToM. To investigate affective ToM in healthy aging and its relationship with executive functions, we examined Reading Mind in the Eyes Test (RMET) performance and executive functions among young and older adults. There was no significant difference between age groups regarding their RMET scores. While affective ToM was correlated to executive functioning within the younger group, short term memory was found to be associated with RMET performance among older participants. Furthermore, within the older group, women performed better than men. Our findings suggest a preserved ability of affective ToM in healthy aging, which appears to be independent of executive functioning.Publisher's Versio