Quanti-qualitative components of the semantic verbal fluency test in cognitively healthy controls, mild cognitive impairment, and dementia subtypes.

This study is aimed to evaluating the underlying cognitive strategies used during Semantic Verbal Fluency (SVF) performance and comparing the differences between cognitively healthy controls (CHC), amnestic and amnestic-multiple domain mild cognitive impairment (a-MCI and a-md-MCI), Alzheimer's disease (AD), Lewy body dementia (LBD), and behavioral variant frontotemporal dementia (bvFTD). The cross-sectional study comprised 236 participants involving 78 CHC individuals, 33 a-MCI and 48 a-md-MCI, 39 AD, 22 LBD, and 16 bvFTD patients. Scores differed significantly when comparing CHC with dementia groups, showing medium to large variances. The best components in distinguishing between CHC and the dementia groups were the SVF-Total score and SVF-Cluster Size variables. CHC showed different performance in the SVF-Cluster Size variable compared with a-md-MCI, AD, and bvFTD; whereas, in the SVF-Mean Cluster Size, CHC differed from MCI's, AD, and LBD. The switching component displayed smaller capacity to differentiate between the clinical groups. The effect size was large comparing AD with bvFTD (1.267) and medium comparing AD with LBD (0.689) using the SVF-Cluster Size variable, but small using the other variables for the comparisons between dementia groups. Quanti-qualitative examination of the SVF may provide a valuable clue in distinguishing CHC from MCI and different dementia subtypes.

[Diagnostic value of cardiac 123I-metaiodobenzylguanidine (123I-MIBG) scintigraphy in Lewy body disorders]. / Valor diagnóstico de la gammagrafía cardíaca con 123I-metaiodobenzilguanidina en las enfermedades con cuerpos de Lewy.

INTRODUCTION: Lewy body disorders such as Parkinson's disease (PD) and Lewy body dementia (LBD) are associated with cardiac sympathetic denervation, which can be visualized on 123I-MIBG scintigraphy. Our objectives were to study the diagnostic value of this technique in Lewy body disorders and its relationship with PD clinical variables. PATIENTS AND METHODS: We studied 90 patients: 51 with PD, 19 with LBD, 9 with multiple system atrophy (MSA) and 11 controls. Scintigraphy images were qualitatively evaluated and early and delayed heart-to-mediastinum ratios (HMR) were calculated. The main confounding factors (ischemic heart disease, diabetes, hypertension and drugs) were controlled by multivariate linear regression analysis. We investigated correlations between scintigraphy variables and PD variables. RESULTS: The delayed HMR, which showed better discriminative ability was 2.03 +/- 0.32 in controls, 1.37 +/- 0.30 in PD (p<0.001 vs controls), 1.47+/-0.45 in LBD (p=0.001 vs controls) and 1.69+/-0.28 in MSA (p=0.02 vs controls; p=0.004 vs PD). This ratio was influenced by PD/LBD diagnosis (beta= -0.638; p<0.001) and to a lesser degree, by ischemic heart disease (beta= -0.244; p=0.028). Optimal cut-off value between PD/LBD and controls was 1.71 (83% sensitivity and 82% specificity). Within the PD group, those with a family history of PD/LB showed higher delayed HMR values (1.65+/-0.34 vs 1.30+/-0.24 without history; p<0.001) and proportion with normal scintigraphy (56% vs 5%; p=0.001). CONCLUSIONS: Cardiac 123I-MIBG scintigraphy is useful in the diagnosis of Lewy body disorders, although its value in PD is conditioned by having a family history of PD.

Addenbrooke's Cognitive Examination validation in Parkinson's disease.

BACKGROUND: There is a clear need for brief, sensitive and specific cognitive screening instruments in Parkinson's disease (PD). OBJECTIVES: To study Addenbrooke's Cognitive Examination (ACE) validity for cognitive assessment of PD patient's using the Mattis Dementia Rating Scale (MDRS) as reference method. A specific scale for cognitive evaluation in PD, in this instance the Scales for Outcomes of Parkinson's disease-Cognition (SCOPA-COG), as well as a general use scale the Mini-mental state examination (MMSE) were also studied for further correlation. METHODS: Forty-four PD patients were studied, of these 27 were males (61%), with a mean (SD) age of 69.5 (11.8) years, mean (SD) disease duration of 7.6 (6.4) years (range 1-25), mean (SD) total Unified Parkinson's Disease Rating Scale (UPDRS) score 37 (24) points, UPDRS III 16.5 (11.3) points. MDRS, ACE and SCOPA-COG scales were administered in random order. All patients remained in on-state during the study. RESULTS: Addenbrooke's Cognitive Examination correlated with SCOPA-COG (r = 0.93, P < 0.0001), and MDRS (r = 0.91 P < 0.0001) and also with MMSE (r = 0.84, P < 0.001). Area under the receiver-operating curve, taking MDRS as the reference test, was 0.97 [95% confidence interval (CI): 0.92-1.00] for ACE, 0.92 (95% CI: 0.83-1.00) for SCOPA-COG and 0.91 (95% CI: 0.83-1.00) for MMSE. Best cut-off value for ACE was 83 points [Sensitivity (Se) = 92%; Specificity (Sp) = 91%; Kappa concordance (K) = 0.79], 20 points for the SCOPA-COG (Se = 92%; Sp = 87%; K = 0.74) and 26 points for MMSE (Se = 61%; Sp = 100%; K = 0.69). CONCLUSION: Addenbrooke's Cognitive Examination appears to be a valid tool for dementia evaluation in PD, with a cut-off point which should probably be set at 83 points, displaying good correlation with both the scale specifically designed for cognitive deficits in PD namely SCOPA-COG, as well as with less specific tests such as MMSE.

Comparison of clinical manifestations in Alzheimer disease and dementia with Lewy bodies.

BACKGROUND: The clinical delineation of dementia with Lewy bodies (DLB) from Alzheimer disease (AD) remains unclear. OBJECTIVES: To compare neuropsychological profiles in DLB and AD among Caribbean Hispanic family members and participants in a population-based epidemiologic sample using extended neuropsychological test batteries and to explore whether these differences were related to heritable factors. DESIGN: Cross-sectional study. SETTING: Clinics in northern Manhattan (New York City), the Dominican Republic, and Puerto Rico. PATIENTS: We compared measures of memory, orientation, language, and executive and visuospatial functioning between patients with DLB vs AD in 2 Caribbean Hispanic cohorts, including a family sample (89 patients with DLB and 118 patients with AD) and an epidemiologic sample (70 patients with DLB and 157 patients with AD). Patients with DLB in the family sample were further categorized as patients having at least 2 family members with DLB or as patients having 1 family member with DLB. MAIN OUTCOME MEASURES: To determine whether observed differences in cognitive profiles were driven by heritable factors, we repeated analyses in the epidemiologic sample after excluding familial cases. We applied general linear models adjusted for age, sex, educational level, disease duration, and apolipoprotein E epsilon4 (OMIM 104310) genotype. RESULTS: Patients with DLB in both samples were more severely impaired in orientation, visuoconstruction, and nonverbal reasoning after controlling for potential confounders. Patients having at least 2 family members with DLB had the most severe impairment in memory, followed by patients having 1 family member with DLB, and then by patients with AD. After excluding familial AD and DLB cases in the epidemiologic sample, the differences between the groups persisted but were attenuated. CONCLUSIONS: Compared with patients having AD, patients having DLB are more severely impaired in various cognitive domains, particularly orientation and visuospatial functioning. The difference seems stronger in familial DLB than in sporadic DLB. Whether this divergence in cognitive functions is caused by gene-gene or gene-environmental interactions remains unclear.

Neural control of the gastrointestinal tract: implications for Parkinson disease.

Disorders of swallowing and gastrointestinal motility are prominent nonmotor manifestations of Parkinson disease (PD). Motility of the gut is controlled both by extrinsic inputs from the dorsal motor nucleus of the vagus (DMV) and paravertebral sympathetic ganglia and by local reflexes mediated by intrinsic neurons of the enteric nervous system (ENS). Both the ENS and the DMV are affected by Lewy body pathology at early stages of PD. This early involvement provides insights into the pathophysiology of gastrointestinal dysmotility in this disorder and may constitute an important step in the etiopathogenesis of Lewy body disease.