Cognition enhancing effect of panax ginseng in Korean volunteers with mild cognitive impairment: a randomized, double-blind, placebo-controlled clinical trial

This study aimed to investigate the cognition-enhancing effect of Panax ginseng. A randomized, double-blind, placebo-controlled clinical trial was conducted to address the cognition-enhancing effects of Panax ginseng. A total of 90 Korean volunteers with mild cognitive impairment participated in this study. All subjects were allocated randomly into ‘Ginseng’ group or ‘Placebo’ group. All subjects were administered 3g of Panax ginseng powder or starch (placebo) for 6 months. The Korean version of the Mini-Mental Status Examination (K-MMSE), Korean version of Instrumental Activities of Daily Living (K-IADL), and Seoul Neuropsychological Screening Battery (SNSB) were used to assess the changes in cognitive function at the end of the 6 month study period. The subjects of the ‘Ginseng’ group improved significantly on the Rey Complex Figure Test (RCFT) immediate recall (P = 0.0405 and P = 0.0342 in per-protocol (PP) and intention-to-treat (ITT) analysis, respectively) and on the RCFT 20-min delayed recall (P = 0.0396 and P = 0.0355 in PP and ITT analysis, respectively) compared with ‘placebo’ group throughout the 6 months of Panax ginseng administration. There were no serious adverse events. These results suggest that Panax ginseng has a cognition-enhancing effect.

Accuracy of Korean-Mini-Mental Status Examination Based on Seoul Neuro-Psychological Screening Battery II Results / 가정의학회지

BACKGROUND: The Korean-Mini-Mental Status Examination (K-MMSE) is a dementia-screening test that can be easily applied in both community and clinical settings. However, in 20% to 30% of cases, the K-MMSE produces a false negative response. This suggests that it is necessary to evaluate the accuracy of K-MMSE as a screening test for dementia, which can be achieved through comparison of K-MMSE and Seoul Neuropsychological Screening Battery (SNSB)-II results. METHODS: The study included 713 subjects (male 534, female 179; mean age, 69.3±6.9 years). All subjects were assessed using K-MMSE and SNSB-II tests, the results of which were divided into normal and abnormal in 15 percentile standards. RESULTS: The sensitivity of the K-MMSE was 48.7%, with a specificity of 89.9%. The incidence of false positive and negative results totaled 10.1% and 51.2%, respectively. In addition, the positive predictive value of the K-MMSE was 87.1%, while the negative predictive value was 55.6%. The false-negative group showed cognitive impairments in regions of memory and executive function. Subsequently, in the false-positive group, subjects demonstrated reduced performance in memory recall, time orientation, attention, and calculation of K-MMSE items. CONCLUSION: The results obtained in the study suggest that cognitive function might still be impaired even if an individual obtained a normal score on the K-MMSE. If the K-MMSE is combined with tests of memory or executive function, the accuracy of dementia diagnosis could be greatly improved.

Constructing a Composite Score for the Seoul Neuropsychological Screening Battery-Core

BACKGROUND AND PURPOSE: The brief version of the Seoul Neuropsychological Screening Battery (SNSB), the SNSB-Core (SNSB-C), has been developed. Although each subtest score of the SNSB-C provides information on different features of broad cognitive functioning or impairment, a composite score is needed to identify the severity of global cognitive impairment. We aimed to develop and validate a composite score of the SNSB-C that would provide a normative-based summary score of global cognitive functioning, especially for differentiating patients with cognitive impairment from normal elderly. METHODS: A normative sample of 1067 elderly was used to develop a composite score of SNSB-C. The composite score was corrected for the effects of age, years of education, and sex by the regression method. Patients with Alzheimer's disease (n=41), vascular dementia (n=40), amnestic mild cognitive impairment (MCI) (n=73), vascular MCI (n=41), and Parkinson's disease with MCI (n=41) were differentiated from a normal sample (n=70) by the uncorrected and corrected composite scores using receiver operating characteristic (ROC) curve analysis. RESULTS: Confirmatory factor analysis showed that the composite score equal weight to each standardized cognitive domain of SNSB-C is appropriate for indexing overall cognitive functioning. The corrected and uncorrected composite scores yielded a satisfactory size of the area under the ROC curve comparable to the Mini Mental State Examination (MMSE). CONCLUSIONS: The composite scores of SNSB-C, especially the corrected score, provide an index of overall cognitive functioning, and they can be used as an alternative to MMSE for screening patients with cognitive impairment.

Caudate Volume Change in Transient Global Amnesia Patients; Voxel-Based Morphometric Study

BACKGROUND: Transient global amnesia (TGA) is characterized by a severe disturbance of memory, lasting less than a day, and complete resolution. However, some authors have suggested the occurrence of permanent memory impairment in such cases. In this study, we investigated whether the gray-matter structure suffers degeneration in TGA, based on the assumption that TGA attacks appear to be related to underlying permanent pathology. METHODS: T1-weighted magnetic resonance imaging data for 20 TGA and 55 normal subjects were analyzed. The gray-matter volume was measured using voxel-based morphometry. The subjects also completed the Seoul Neuropsychological Screening Battery (SNSB). RESULTS: The gray-matter volume was reduced in the left superior frontal gyrus, right precentral gyrus, right superior frontal gyrus, left caudate nucleus, left precentral gyrus, left post central gyrus, and both putamens. The SNSB revealed the presence of selective neuropsychological dysfunctions after clinical recovery. Most of the cases exhibited attention deficit, and difficulties in copying of the Rey-Osterrieth Complex Figure, and in the Seoul verbal learning test. CONCLUSIONS: Left caudate nucleus atrophy could explain the attention deficit and memory impairment experienced in these TGA patients. Many patients with TGA have neuropsychological dysfunctions even after they appear to be clinically improved.

Concomitant PET Brain Imaging and Neuropsychological Assessment in Transient Global Amnesia

BACKGROUND: Transient global amnesia (TGA) is one of the most striking syndromes in clinical neurology. In recent years, with the development of new types of imaging methods, particularly the clinical application of PET may have helped the medical personnel to understand the nature of this remarkable syndrome. The purpose of this study is to evaluate the common lesion of TGA by 18FDG-PET through Statistical Parametric Mapping (SPM) analysis and compare them with the results of the neuropsychological tests. METHODS: We studied prospectively 10 patients diagnosed clinically as TGA. They received brain MRI and/or CT and PET of the brain with 18FDG as the tracer. The results of the brain PET imaging of patients were analyzed with SPM and were compared with those of 15 normal controls. They also received SNSB and the Korean version of the Rey-Kim memory test. RESULTS: No obvious abnormality was found in the visual analysis of MRI or CT scans of the 10 patients with TGA. However SPM analysis of the brain PET imaging displayed low metabolic areas in the left primary motor and sensory cortex, bilateral anterior cingulate gyrus and right posterior thalamus. SNSB revealed multiple cognitive dysfunctions including visuospatial functions, visual memory, verbal memory, calculation, attention and frontal executive functions. In 5 patients, memory quotients were within the low average range. CONCLUSIONS: SPM analysis of PET imaging displayed multiple low metabolic areas and these lesions were roughly correlated with the results of neuropsychological tests which showed defects of visuospatial functioning and frontal executive functioning.