Abstract. Decreased delayed recall, decreased amyloid-β peptides (Aβ1−42), and increased tau protein concentration in cerebrospinal fluid (CSF) are generally regarded to be valid neuropsychological and biological markers for Alzheimer's disease (AD). Previous studies failed to demonstrate clear-cut correlations between neuropsychological impairment and CSF markers. In this study we test recent models of disease progression, that propose that changes in CSF biomarkers already reach a plateau in a preclinical phase, before cognitive decline begins, that is, even before MCI can be diagnosed. We recruited 73 patients with probable AD (n = 36) and mild cognitive impairment (MCI) (amnesic MCI = 25; non-amnesic MCI = 12). We used the CERAD-NP, a widely used neuropsychological battery with norms for different age and education groups, and additional neuropsychological tests for assessing the cognitive profile of these patient groups. We found a significant correlation between Aβ1−42 in the CSF and memory performance for amnesic MCI patients, but not for non-amnesic MCI and AD patients. All other correlations between cognitive tasks and Aβ1−42 were not significant. Tau protein concentration in the CSF was not correlated with any neuropsychological marker in any of the patients groups. We conclude that the decrease of Aβ1−42 in the CSF mirrors disease progression during the early stages up into AD and therefore is not restricted to the preclinical phase. The decrease of Aβ1−42 reaches a plateau only in the full blown demented syndrome and further functional disease progression is then related to neurodegeneration without further reduction of Aβ1−42 in the CSF.
Background and purpose: As patients with abnormal baseline coagulation were excluded from the large randomized trials, the safety of intravenous thrombolysis after ischaemic stroke in this patient population remains controversial. Methods: We assessed the risk of symptomatic intracerebral hemorrhage (SICH) after systemic thrombolysis in patients with elevated baseline international normalized ratios (INRs) ( ‡1.3) or activated partial thromboplastin times (aPTT) (>37 s) using a prospectively recorded database from 2006 to 2010. An intracerebral hemorrhage leading to a deterioration of ‡4 points on the National Institutes of Health Stroke scale (NIHSS) was classified as symptomatic. Results: Amongst 688 patients (mean age, 72 years; median NIHSS, 11, median onset-to-treatment time, 135 min), 36 patients (5%) had an abnormal baseline coagulation. Twenty-nine of these patients had taken oral anticoagulants leading to elevated baseline INRs (median INR: 1.5; IQR 1.4-1.9), whereas seven patients had elevated aPTTs because of heparin therapy (n = 2), a coagulation disorder (n = 2), or for unknown reasons (n = 3). The rate of SICH did not differ significantly between patients with abnormal and normal baseline coagulation (4.4% vs. 0%; P = 0.6). Moreover, the in-hospital mortality was not significantly different between both treatment groups (8.3% in patients with abnormal baseline coagulation vs. 8.7% in patients with normal baseline coagulation, P = 1.0). Conclusions: The risk of SICH following intravenous thrombolysis after ischaemic stroke does not appear to be increased in patients with abnormal baseline coagulation.
Two recent reviews on neuropsychological assessment argue that Alzheimer’s disease (AD) is characterized by deficits in delayed recall and that this allows differentiating AD from other types of dementia. We attempted to differentiate patients with AD and amnestic mild cognitive impairment (MCI) from patients with fronto-subcortical dementia, normal pressure hydrocephalus and vascular dementia using a simple picture recognition task. We examined 130 patients, 89 with dementia and 41 with MCI. The combination of the CERAD-NP savings score and the number of false recognitions yielded a sensitivity of 100% for identifying AD patients. Moreover, adding the score for false recognitions to that of delayed recall improved the specificity of the diagnosis from 50% to 90%. After matching the groups on memory performance, the AD group still produced more false recognitions. The results suggest that delayed recall impairment and recognition errors stem from different sources. We also found that the number of false recognitions differs between amnestic and non-amnestic MCI patients. The quality of the differential diagnosis may therefore be enhanced significantly by taking into account both delayed recall and false recognitions provoked by a picture recognition task.
Severe memory impairment forms the core symptom of Alzheimer's disease (AD), which is present early in the disease course. Recent studies show that AD patients not only suffer from forgetfulness, but also differ in their response bias, when having to decide whether information has been perceived recently, or whether it is only familiar or semantically related to perceived information. Changes in total tau-protein and amyloid-beta (Abeta) (1-42) concentration in cerebrospinal fluid are also features of AD, and they predict conversion from mild cognitive impairment to dementia. In this study we correlated recognition scores with total tau and Abeta (1-42) concentrations in patients with suggested dementia. We studied 40 patients and 21 healthy controls, using an incidental recognition memory task and a neuropsychological test battery. False recognition scores correlated with delayed recall and with Abeta(1-42), and Abeta (1-42) tended to correlate with delayed recall. Total tau, however, did not correlate with memory scores or with neuropsychological performance in general. We suggest that Abeta (1-42) may indicate a reduction in the specificity of the neuronal response in the limbic cortex, due to agglomeration of plaques. This process might be more specific for AD than the increase of tau, and therefore it is stronger correlated with recognition errors.
Background Primary progressive multiple sclerosis (PPMS) is characterised by gradual worsening of disability from symptom onset. Knowledge about the natural course of PPMS remains limited. Methods PPMS patients from the German NeuroTransData (NTD) MS registry with data from 56 outpatient practices were employed for retrospective cross-sectional and longitudinal analyses. The cross-sectional analysis included a contemporary PPMS cohort with a documented visit within the last 2 years before index date (1 Jan 2021). The longitudinal analysis included a disease modifying therapy (DMT)-naïve population and focused on the evolution of expanded disability status scale (EDSS) from the first available assessment at or after diagnosis within the NTD registry to index date. Outcome measures were estimated median time from first EDSS assessment to first 24-week confirmed EDSS ≥ 4 and ≥ 7. Besides EDSS change, the proportion of patients on disability pension were described over time. Results The cross-sectional analysis included 481 PPMS patients (59.9% female, mean [standard deviation, SD] age 60.5 [11.5] years, mean [SD] EDSS 4.9 [2.1]). Estimated median time from first EDSS assessment after diagnosis to reach 24-week confirmed EDSS ≥ 4 for DMT-naïve patients was 6.9 years. Median time to EDSS ≥ 7 was 9.7 years for 25% of the population. Over a decade mean (SD) EDSS scores increased from 4.6 (2.1) to 5.7 (2.0); the proportion of patients on disability pension increased from 18.9% to 33.3%. Conclusions This study provides first insights into the German NTD real-world cohort of PPMS patients. Findings confirm the steadily deteriorating course of PPMS accompanied by increasingly limited quality of life.
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