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B F Boeve

Publications and source records attributed to B F Boeve.

At least 37 records · Page 2Linked to original sources
PubMed2003

Synucleinopathy pathology and REM sleep behavior disorder plus dementia or parkinsonism.

OBJECTIVE: To determine if synucleinopathy pathology is related to REM sleep behavior disorder (RBD) plus dementia or parkinsonism. METHODS: The clinical and neuropathologic findings were analyzed on all autopsied cases evaluated at Mayo Clinic Rochester from January 1990 to April 2002 who were diagnosed with RBD and a neurodegenerative disorder. Ubiquitin and/or alpha-synuclein immunocytochemistry was used in all cases. The clinical and neuropathologic diagnoses were based on published criteria. RESULTS: Fifteen cases were identified (14 men). All had clear histories of dream enactment behavior, and 10 had RBD confirmed by polysomnography. RBD preceded dementia or parkinsonism in 10 (66.7%) patients by a median of 10 (range 2 to 29) years. The clinical diagnoses included dementia with Lewy bodies (DLB) (n = 6); multiple-system atrophy (MSA) (n = 2); combined DLB, AD, and vascular dementia (n = 1); dementia (n = 1); dementia with parkinsonism (n = 1); PD (n = 1); PD with dementia (n = 1); dementia/parkinsonism/motor neuron disease (n = 1); and AD/Binswanger's disease (n = 1). The neuropathologic diagnoses were Lewy body disease (LBD) in 12 (neocortical in 11 and limbic in 1) and MSA in 3. Three also had argyrophilic grain pathology. In the LBD cases, concomitant AD pathology was present in six (one also with Binswanger's pathology, and one also with multiple subcortical infarcts). CONCLUSION: In the setting of degenerative dementia or parkinsonism, RBD often reflects an underlying synucleinopathy.

Age of Onset↗
PubMed2003

Neuropathology of cognitively normal elderly.

Despite general agreement about the boundaries of Alzheimer disease (AD), establishing a maximum limit for Alzheimer-type pathology in cognitively intact individuals might aid in defining more precisely the point at which Alzheimer pathology becomes clinically relevant. In this study, we examined the neuropathological changes in the brains of 39 longitudinally followed. cognitively normal elderly individuals (24 women, 15 men; age range 74-95, median 85 years). Neuropathological changes of the Alzheimer type were quantified by determining neurofibrillary tangle (NFT) staging by the method of Braak and Braak and by quantification of the abundance of diffuse, cored, and neuritic plaque burden using the scheme developed by the Consortium to Establish a Registry for Alzheimer Disease (CERAD). Vascular, Lewy body, and argyrophilic grain pathology were also assessed. We found 34 subjects (87%) with a Braak stage <IV; 32 subjects (82%) with less than moderate numbers of cored plaques and 37 subjects (95%) with less than moderate numbers of tau-positive neuritic plaques. Many subjects had moderate or frequent diffuse plaques (n = 19, 49%). By the National Institute on Aging-Reagan Institute (NIA-RI) criteria, none of our cases met criteria for high "likelihood" of AD. Four met NIA-RI criteria for intermediate "likelihood." Seven cases met CERAD criteria for possible AD. Nineteen met Khachaturian criteria for AD. Only 1 subject had neocortical Lewy bodies. Small, old infarcts were common, but no subjects had more than 2 of these and none had a single large infarction. Thus, the majority of individuals who are cognitively normal near the time of their death have minimal amounts of tau-positive neuritic pathology (Braak stage <IV and neuritic plaques <6 per x100 field in the most affected neocortical region). The few subjects with more severe AD pathology can be expected based on incidence rates of AD in the very elderly.

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PubMed2002

Antemortem MRI findings correlate with hippocampal neuropathology in typical aging and dementia.

OBJECTIVES: To assess the diagnostic specificity of MRI-defined hippocampal atrophy for AD among individuals with a variety of pathologically confirmed conditions associated with dementia as well as changes attributable to typical aging, and to measure correlations among premortem MRI measurements of hippocampal atrophy, mental status examination performance, and the pathologic stage of AD. METHODS: An unselected series of 67 individuals participating in the Mayo Alzheimer's Disease Research Center/Alzheimer's Disease Patient Registry who had undergone a standardized antemortem MRI study and also postmortem examination were identified. Hippocampal volumes were measured from antemortem MRI. Each postmortem specimen was assigned a pathologic diagnosis and in addition, the severity of AD pathology was staged using the method of Braak and Braak. RESULTS: Individuals with an isolated pathologic diagnosis of AD, hippocampal sclerosis, frontotemporal degeneration, and neurofibrillary tangle--only degeneration usually had substantial hippocampal atrophy, while those with changes of typical aging did not. Among all 67 subjects, correlations (all p < 0.001) were observed between hippocampal volume and Braak and Braak stage (r = -0.39), between hippocampal volume and Mini-Mental State Examination (MMSE) score (r = 0.60), and between MMSE score and Braak and Braak stage (r = -0.41). CONCLUSIONS: Hippocampal atrophy, while not specific for AD, was a fairly sensitive marker of the pathologic AD stage (particularly among subjects with isolated AD pathology [r = -0.63, p = 0.001]) and consequent cognitive status.

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PubMed2002

Corticobasal degeneration and frontotemporal dementia presentations in a kindred with nonspecific histopathology.

We report the clinical, neuropsychological, electroencephalographic and radiologic findings in a kindred with varying clinical presentations of a neurodegenerative disorder. Postmortem examination of one member with clinically suspected corticobasal degeneration (CBD) revealed nonspecific histopathology maximally involving the frontoparietal cortex with negligible degenerative changes in the basal ganglia and substantia nigra. The findings in this and other kindreds demonstrate that (1) similar findings on ancillary testing can occur in relatives presumably suffering from the same pathophysiologic process despite dissimilar clinical presentations, (2) the 'CBD syndrome' is not specific for CBD, (3) extrapyramidal dysfunction can exist in the absence of appreciable basal ganglia and nigral degeneration, (4) nonspecific histopathology can underlie familial focal/asymmetric cortical degeneration syndromes and (5) many of the findings in CBD are comparable to those reported in frontotemporal dementia.

Basal Ganglia Diseases↗
PubMed2001

Narcolepsy associated with other central nervous system disorders.

The authors identified patients with the coexistence of narcolepsy and another CNS disorder seen between 1975 and 1998 at their institution. Eighteen patients were identified, nine with narcolepsy commencing within 1 year before or after the other disorder. Seven patients (39%) had hypothalamic-pituitary syndromes. When they occur together, narcolepsy and other CNS disorders frequently emerge at about the same time, suggesting a causative relationship. Hypothalamic-pituitary pathology was the most common association.

Brain↗
PubMed2001

Association of REM sleep behavior disorder and neurodegenerative disease may reflect an underlying synucleinopathy.

Our objective was to examine whether rapid eye movement (REM) sleep behavior disorder occurs in disproportionally greater frequency in multiple system atrophy (MSA), Parkinson's disease (PD), and dementia with Lewy bodies (DLB), collectively known as the synucleinopathies, compared to other nonsynucleinopathy neurodegenerative disorders. In study 1, we reviewed the clinical records of 398 consecutive patients evaluated at Mayo Clinic Rochester for parkinsonism and/or cognitive impairment. The frequency of suspected and polysomnogram (PSG)-confirmed REM sleep behavior disorder (RBD) among subjects with the synucleinopathies MSA, PD, or DLB was compared to the frequency among subjects with the nonsynucleinopathies Alzheimer's disease (AD), frontotemporal dementia (FTD), corticobasal degeneration (CBD), progressive supranuclear palsy (PSP), mild cognitive impairment (MCI), primary progressive aphasia (PPA), and posterior cortical atrophy (PCA). In study 2, we reviewed the clinical records of 360 consecutive patients evaluated at Mayo Clinic Jacksonville for parkinsonism and/or cognitive impairment. The frequency of probable RBD among patients with PD and DLB was compared to the frequency among patients with AD and MCI. In study 3, we reviewed the brain biopsy or postmortem autopsy diagnoses of 23 Mayo Clinic Rochester patients who had been clinically examined for possible RBD and a neurodegenerative disorder. In study 1, patients with MSA, PD, or DLB were more likely to have probable and PSG-confirmed RBD compared to subjects with the nonsynucleinopathies (probable RBD 77/120=64% vs. 7/278=3%, p < 0.01; PSG-confirmed RBD 47/120=39% vs. 1/278=0%, p < 0.01). In study 2, patients with PD and DLB were more likely to have probable RBD compared to those with AD and MCI (56% vs. 2%, p < 0.01). In study 3, of the 23 autopsied patients who had been questioned about possible RBD, 10 were clinically diagnosed with RBD. The neuropathologic diagnoses in these 10 included Lewy body disease in nine, and MSA in one. Of the other 13 cases, 12 did not have a history suggesting RBD, and the one case who did had normal electromyographic atonia during REM sleep on PSG and autopsy findings of PSP. Only one of these 13 had a synucleinopathy. The positive predictive values for RBD indicating a synucleinopathy for studies 1-3 were 91.7%, 94.3%, and 100.0%, respectively. Clinically suspected and PSG-proven RBD occurs with disproportionally greater frequency in MSA, PD, and DLB compared to other neurodegenerative disorders. In the setting of degenerative dementia and/or parkinsonism, we hypothesize that RBD is a manifestation of an evolving synucleinopathy.

Adult↗
PubMed2001

Understanding the diagnostic capabilities of cognitive tests.

Statistics (i.e., sensitivity, specificity, hit rates, positive and negative predictive values, odds ratios, and likelihood ratios) that best describe a diagnostic test's ability to classify persons as either "impaired" or "normal," but that are not commonly reported in neuropsychological research, are reviewed. These statistics are applied to Mayo Cognitive Factor Scale scores (MCFS; Smith et al., 1994) to demonstrate information that can be acquired about the diagnostic capabilities of cognitive tests as they are commonly used in clinical settings. Multivariate analyses then generated a statistical model that combines MCFS scores and improves on the diagnostic capabilities of the individual MCFS scores. This model enjoys better diagnostic power than individual scores. It establishes that cognitive testing that uses multiple measures is very good at differentiating normal from impaired cognitive states. Information is also provided that helps clinicians quantify a person's risk for cognitive impairment based on specific cognitive test score(s).

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PubMed2001

Mild cognitive impairment and Alzheimer disease: regional diffusivity of water.

PURPOSE: To compare the regional diffusivity of water in the brains of normally aging elderly people and patients with mild cognitive impairment (MCI) or Alzheimer disease. MATERIALS AND METHODS: Magnetic resonance images were obtained in 21 patients with Alzheimer disease, 19 patients with MCI, and 55 normally aging elderly control subjects without evidence of cognitive impairment. Regions of interest were drawn to compare the apparent diffusion coefficient (ADC) and the anisotropy index (AI) in frontal, parietal, temporal, occipital, anterior, and posterior cingulate white matter (WM), and the thalami and hippocampi. RESULTS: Hippocampal ADC was higher in MCI and Alzheimer disease patients than in control subjects. ADC of the temporal stem and posterior cingulate, occipital, and parietal WM was higher in Alzheimer disease patients than in control subjects. Except for occipital AI, which was lower in MCI patients than in control subjects, there were no differences in AI among the three groups for any of the regions. CONCLUSION: Hippocampal ADC was significantly different between control subjects and MCI patients, many of whom likely have preclinical Alzheimer disease. Elevation in hippocampal ADC may reflect early ultrastructural changes in the progression of Alzheimer disease.

Aged↗
PubMed2000

Rates of hippocampal atrophy correlate with change in clinical status in aging and AD.

BACKGROUND: The cognitive continuum in the elderly population can be conceptually divided into those who are functioning normally (control subjects), those with a mild cognitive impairment (MCI), and those with probable AD. OBJECTIVES: To test the hypothesis that the annualized rates of hippocampal atrophy differ as a function of both baseline and change in clinical group membership (control, MCI, or AD). METHODS: The authors identified 129 subjects from the Mayo Clinic AD Research Center/AD Patient Registry who met established criteria for normal control subjects, MCI, or probable AD, both at entry and at the time of a subsequent clinical follow-up evaluation 3 +/- 1 years later. Each subject underwent an MRI examination of the head at the time of the initial assessment and at follow-up clinical assessment; the annualized percentage change in hippocampal volume was computed. Subjects who were classified as controls or patients with MCI at baseline could either remain cognitively stable or could decline to a lower functioning group over the period of observation. RESULTS: The annualized rates of hippocampal volume loss for each of the three initial clinical groups decreased progressively in the following order: AD > MC > control. Within the control and MCI groups, those who declined had a significantly greater rate of volume loss than those who remained clinically stable. The mean annualized rates of hippocampal atrophy by follow-up clinical group were: control-stable 1.73%, control-decliner 2.81%, MCI-stable 2.55%, MCI-decliner 3.69%, AD 3. 5%. CONCLUSION: Rates of hippocampal atrophy match both baseline cognitive status and the change in cognitive status over time in elderly persons who lie along the cognitive continuum from normal to MCI to AD.

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PubMed2000

Regional metabolic patterns in mild cognitive impairment and Alzheimer's disease: A 1H MRS study.

BACKGROUND: Mild cognitive impairment (MCI) is a recently described transitional clinical state between normal aging and AD. Assuming that amnestic MCI patients had pathologic changes corresponding to an early phase and probable AD patients to a later phase of the disease progression, the authors could approximate the temporal course of proton MR spectroscopic (1H MRS) alterations in AD with a cross-sectional sampling scheme. METHODS: The authors compared 1H MRS findings in the superior temporal lobe, posterior cingulate gyri, and medial occipital lobe in 21 patients with MCI, 21 patients with probable AD, and 63 elderly controls. These areas are known to be involved at different neurofibrillary pathologic stages of AD. RESULTS: The N-acetylaspartate (NAA)/creatine (Cr) ratios were significantly lower in AD patients compared to both MCI and normal control subjects in the left superior temporal and the posterior cingulate volumes of interest (VOI) and there were no between-group differences in the medial occipital VOI. Myoinositol (MI)/Cr ratios measured from the posterior cingulate VOI were significantly higher in both MCI and AD patients than controls. The choline (Cho)/Cr ratios measured from the posterior cingulate VOI were higher in AD patients compared to both MCI and control subjects. CONCLUSION: These findings suggest that the initial 1H MRS change in the pathologic progression of AD is an increase in MI/Cr. A decrease in NAA/Cr and an increase in Cho/Cr develop later in the disease course.

Aged↗
PubMed2000

Usefulness of MRI measures of entorhinal cortex versus hippocampus in AD.

OBJECTIVE: MRI-based measurements of hippocampal atrophy are a sensitive indicator of the early pathologic degeneration of the medial temporal lobe in AD. However, AD pathology appears first in the transentorhinal/entorhinal cortex, not the hippocampus. The authors tested the hypothesis that MRI-based measurements of the entorhinal cortex are more sensitive than measurements of hippocampal volume in discriminating among three clinical groups; controls, patients with a mild cognitive impairment (MCI), and patients with mild probable AD. METHODS: The authors studied 30 controls, 30 patients with MCI, and 30 patients with AD who were matched among clinical groups on age, gender, and education. All underwent a standardized MRI protocol from which the authors made measurements of hippocampal volume, entorhinal cortex volume, and the cumulative length of the medial border of the entorhinal cortex. RESULTS: Pairwise intergroup differences (p < 0.01) were found for all MRI measurements with the exception of the cumulative length of the entorhinal cortex, which did not differentiate controls from MCI patients. Whereas the hippocampal and entorhinal cortex volume measurements provided slightly better intergroup discrimination than the entorhinal distance measurement, overall differences in discriminating ability among the three MRI measurements were minor. CONCLUSIONS: Despite the theoretical rationale for the superiority of entorhinal measurements in early AD, the authors found MRI measurements of the hippocampus and entorhinal cortex were approximately equivalent at intergroup discrimination. Measurements of the hippocampus may be preferable because MRI depiction of the boundaries of the entorhinal cortex can be obscured by anatomic ambiguity, image artifact, or both.

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PubMed2000

Memory and MRI-based hippocampal volumes in aging and AD.

OBJECTIVE: To demonstrate structural-functional relationships between MRI-based volumetric measurements of medial temporal lobe structures and cognitive function. BACKGROUND: Previous work has documented the ability of MRI-based measurements of the hippocampus to discriminate between age-matched control subjects and patients with very mild AD. Relatively less is known about the correlation between medial temporal lobe structures and cognitive functions. METHOD: We evaluated structural-functional relationships among the hippocampal formation, parahippocampal gyrus, and amygdala, and measures of memory, language, and general cognitive performance in 220 probable AD patients and normal control subjects. Standardized instruments of memory and general cognitive function were used to assess subjects enrolled in a longitudinal study of aging and dementia. RESULTS: The volume of the hippocampal formation predicted performance on most acquisition and recall measures across the spectrum of normal aging and AD. If the groups were segregated, most of the expected associations between medial temporal lobe structures and memory measures were observed in the AD patients. CONCLUSION: MRI-based hippocampal volumetry accurately depicts the structural-functional relationships between memory loss and hippocampal damage across the spectrum from normal aging to dementia.

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PubMed2000

Diagnostic accuracy of four approaches to interpreting neuropsychological test data.

The diagnostic accuracy of 4 approaches to interpreting neuropsychological test results are evaluated in 672 cognitively normal and 407 cognitively impaired persons using the Mayo Cognitive Factor Scales (G. E. Smith et al., 1994). The interpretation approaches studied are absolute scores, difference scores, profile variability, and change scores at 1- to 2-year test-retest intervals. All dependent measures were "highly significant" when diagnostic groups were compared on null hypothesis significance testing analyses. In contrast, varied accuracy rates were obtained when each measure's ability to correctly classify individuals was evaluated relative to overall diagnostic accuracy. Odds ratios were also highly varied and ranged from < or = 1.0 (i.e., chance) to 34.9. The clinical usefulness of absolute scores and difference scores in data interpretation is supported. Neither profile variability measures nor measures of change over time were diagnostically useful.

Aged↗
PubMed2000

Rapid eye movement sleep behaviour disorder: demographic, clinical and laboratory findings in 93 cases.

We describe demographic, clinical, laboratory and aetiological findings in 93 consecutive patients with rapid eye movement (REM) sleep behaviour disorder (RBD), which consists of excessive motor activity during dreaming in association with loss of skeletal muscle atonia of REM sleep. The patients were seen at the Mayo Sleep Disorders Center between January 1, 1991 and July 31, 1995. Eighty-one patients (87%) were male. The mean age of RBD onset was 60.9 years (range 36-84 years) and the mean age at presentation was 64.4 years (37-85 years). Thirty-two per cent of patients had injured themselves and 64% had assaulted their spouses. Subdural haematomas occurred in two patients. Dream content was altered and involved defence of the sleeper against attack in 87%. The frequency of nocturnal events decreased with time in seven untreated patients with neurodegenerative disease. MRI or CT head scans were performed in 56% of patients. Although four scans showed brainstem pathology, all of these patients had apparently unrelated neurodegenerative diseases known to be associated with RBD. Neurological disorders were present in 57% of patients; Parkinson's disease, dementia without parkinsonism and multiple system atrophy accounted for all but 14% of these. RBD developed before parkinsonism in 52% of the patients with Parkinson's disease. Five of the 14 patients with multiple system atrophy were female, and thus the strong male predominance in RBD is less evident in this condition. Psychiatric disorders, drug use or drug withdrawal were rarely causally related to RBD. Clonazepam treatment of RBD was completely or partially successful in 87% of the patients who used the drug. We conclude that RBD is a well-defined condition and that descriptions from different centres are fairly consistent. It is commonest in elderly males and may result in serious morbidity to patients and bed partners. There is a strong relationship to neurodegenerative disease, especially Parkinson's disease, multiple system atrophy and dementia, and neurologists should explore the possibility of RBD in patients with these conditions. RBD symptoms may be the first manifestations of these disorders and careful follow-up is needed. Neuroimaging is unlikely to reveal underlying disorders not suspected clinically. We confirm the effectiveness of clonazepam, but note that attention to the safety of the bed environment may be sufficient for patients with contraindications to the drug.

Adult↗
PubMed1999

Nonvasculitic autoimmune inflammatory meningoencephalitis (NAIM): a reversible form of encephalopathy.

Five patients, age 54 to 80 years, presented between 3 weeks and 18 months after symptomatic onset of progressive cognitive decline, psychosis, and unsteady gait that proved to be due to a steroid-responsive nonvasculitic autoimmune inflammatory meningoencephalitic syndrome. CSF examination showed elevated immunoglobulin (Ig)G index and IgG synthesis rate in all three patients in whom it was checked, and brain biopsy revealed perivascular lymphocytic infiltrates without vessel wall invasion.

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PubMed1999

Pathologic heterogeneity in clinically diagnosed corticobasal degeneration.

BACKGROUND: Early reports suggested that corticobasal degeneration (CBD) is a distinct clinicopathologic entity. Because patients have had a fairly consistent constellation of clinical and laboratory findings, many have proposed that the pathologic diagnosis can be surmised with confidence during life. OBJECTIVE: To analyze the pathologic findings in a large series of cases with clinically diagnosed CBD. METHODS: Using the medical research linkage system of the Mayo Clinic for the period January 1990 to December 1997, we identified cases diagnosed during life with CBD who subsequently underwent autopsy. All patients had progressive asymmetric rigidity and apraxia (except one with rigidity but no apraxia) with other findings, suggesting additional cortical and basal ganglionic dysfunction. All cases underwent standardized neuropathologic examination with the distribution and severity of the pathologic changes determined for each case and the pathologic diagnoses based on currently accepted criteria. RESULTS: Thirteen cases were identified. The pathologic diagnoses were CBD in seven, AD in two, and one each for progressive supranuclear palsy, Pick's disease, nonspecific degenerative changes, and Creutzfeldt-Jakob disease. Two cases had negligible basal ganglia and nigral degeneration despite previously having obvious extrapyramidal signs. However, all patients had focal or asymmetric cortical atrophy with coexisting neuronal loss and gliosis with or without status spongiosis, which was maximal in the parietal and frontal cortical regions. CONCLUSIONS: The constellation of clinical features considered characteristic of CBD is associated with heterogeneous pathologies. Furthermore, this syndrome can occur in the absence of basal ganglia and nigral degeneration. The one invariable pathologic abnormality in patients with this syndrome, however, is asymmetric parietofrontal cortical degeneration. At present, accurate diagnosis of CBD requires tissue examination.

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