The pattern of cognitive-functional decline in elderly essential tremor patients: an exploratory-comparative study with Parkinson's and Alzheimer's disease patients.

OBJECTIVE: Essential tremor (ET) is a neurological disorder that produces motor, cognitive, and functional disability. However, there has been no investigation linking cognitive impairment with functional disability in ET. Therefore, we examine the similarities and differences between ET, Alzheimer's disease (AD), and Parkinson's disease (PD) in terms of the linkage between cognitive and functional impairment. DESIGN: Thirty-four ET, 26 PD, and 31 AD subjects were tested for cognition (Mini-Mental State Examination [MMSE]), motor disability (United Parkinson's Disease Rating Scale part III [UPDRS-III]), and functional disability (Minimum Data Set-Activities of Daily Living Section [MDS-ADL]). RESULTS: As expected, in PD and AD subjects, MDS-ADL scores significantly correlated with UPDRS-III and MMSE scores. The ET subjects showed a different pattern of functional disability with MDS-ADL scores significantly correlating only with MMSE scores, and with the orientation MMSE modalities. CONCLUSIONS: Our findings highlight the need to be more cognizant of the nonmotor aspects of ET, which in some patients may be more functionally disabling than the motor features themselves.

Parkinson's disease dementia: a diminished role for the Lewy body.

The literature currently views Lewy bodies as central in the pathogenesis of Parkinson's disease dementia (PDD) when Alzheimer's disease (AD) or vascular pathology is not present. Because the neuropathology of PDD is not well understood, the pathological features of PDD were characterized in eighteen PD brain specimens using published criteria for AD, Diffuse Lewy Body Disease (DLBD), and Vascular Disease as a framework. Among the PD dementia (n=16) subjects, 3 (19%) did not have LBs outside of the brain stem, nor AD or vascular pathology. In two additional cases, one did have rare LBs in the neocortex and cingulate gyrus. However, these two cases did not meet the diagnostic criteria for DLBD. Beyond these 5 cases, the remaining PD dementia subjects fitted a classical pathological profile consistent with AD (38%), vascular disease (12.5%), DLBD (6%), or a combination of these pathologies (12.5%). The findings from this study do not support the hypothesis that LBs are the main substrate for dementia in PD. More research with a larger sample size is needed to determine whether the LB may be a secondary phenomenon and/or an "innocent-bystander". The entire role of the LB in PD dementia is again brought into question.

Serum lipids are related to Alzheimer's pathology in nursing home residents.

BACKGROUND: Studies of associations between serum lipids and Alzheimer's disease (AD) or other dementias in the elderly show conflicting results, perhaps due to misclassification of the various dementias. METHODS: For 358 nursing home residents, serum lipids were studied at admission and diagnoses established at autopsy. We used defined neuropathological criteria to distinguish the presence of AD and to avoid errors of clinical dementia assessment. RESULTS: Residents with any AD pathology, as compared to those without AD pathology, had higher mean serum total cholesterol (TC; 200.4 vs. 185.9 mg/dl; p = 0.02) and higher mean low-density lipoprotein cholesterol (LDL; 124.5 vs. 111.5 mg/dl; p = 0.03). Further, mean TC, LDL and high-density lipoprotein cholesterol levels all increased progressively with increasing pathological certainty of AD (p for trend = 0.001, 0.02 and 0.02). CONCLUSIONS: TC and LDL were significantly related to pathologically defined AD. If serum lipids have a role in the pathogenesis of AD, interventions may modify the course of disease.

The neuropathological basis for depression in Parkinson's disease.

Depression is found in 30-40% of all patients with Parkinson's disease (PD), but its etiology is unclear. Using neuropathology as a signpost for neurotransmitter function, we investigated the prevalence of pathological features found at postmortem and sought to uncover differences between depressed (n=11) and non-depressed (n=9) elderly PD patients. The results indicate a higher prevalence of pathological features in depressed compared to non-depressed PD patients, particularly in catecholamine areas of the brain; the locus coeruleus (neuronal loss: odds ratio=7.2, p=08; gliosis: odds ratio=18.0, p=008); dorsal vagus nerve (gliosis: odds ratio=7.63, p<0.05), and substantia nigra pars compacta (gliosis: odds ratio=2.85, ns). However, neuropathological differences were absent in the dorsal raphe nuclei, amygdala, and cortical regions. Our evidence suggests that depression in PD is related more to catecholaminergic than serotonergic system dysfunction.

The autopsy and the elderly patient in the hospital and the nursing home: enhancing the quality of life.

The autopsy is the ultimate "peer review." Yet the autopsy has nearly disappeared from hospitals in the United States and around the world. It is rarely performed in the nursing home or other long-term care (LTC) setting. As a result, all of society has lost much, in terms of quality of health care, the skills of physicians, and insights gained through autopsy-based research. The elderly have the lowest rate of autopsies of any age group. This is a paradox, since the greatest quality and quantity of knowledge would accrue from the often surprising findings revealed at autopsy that reflect the acknowledged "multiple simultaneous illnesses" occurring in older persons. This review and analysis describe why autopsy rates have fallen in hospitals and offer rationales and solutions for reversing this trend in the nursing home and other LTC settings.

The effects of withdrawal of dopaminergic medication in nursing home patients with advanced parkinsonism.

OBJECTIVE: To determine the effects of dopaminergic medication withdrawal in an elderly, demented and minimally ambulatory nursing home population with parkinsonism in New York City. METHODS: In our double-blind, randomized study, 11 patients (7 males, 4 females) were randomized into 2 groups: one group underwent levodopa medication withdrawal (experimental group) and the other group continued on their levodopa (control group). Patients were evaluated weekly over the course of a month with a neurologic examination and a series of assessment tools, including the motor UPDRS (Unified Parkinson's disease rating scale), Hoehn and Yahr staging scale, the Mini-Mental State Examination (MMSE) and the Nursing Assistant Behavioral Detection Form. SETTING: An academic nursing home in New York City. RESULTS: The patients had a mean age of 82.00 +/- 10.14 years, with a mean MMSE score of 9.50 +/- 6.60 out of 30.00 maximum. The control and experimental groups did not differ significantly with respect to age (P = .52), dementia severity (P = .35), nor severity of PD symptoms as measured by the UPDRS (P = .22) and Hoehn and Yahr staging (P = .65). Overall, no significant changes were observed between the control and experimental groups in cognitive, behavioral, and motor function across each time period. Of interest, 2 of the drug withdrawal patients showed modest improvements in cognitive function as measured by the MMSE. CONCLUSION: Our findings suggest that in patients with advanced parkinsonism and dementia, dopaminergic medication withdrawal may be a feasible way to reduce polypharmacy and potential medication-related side effects, with a minimal risk of worsening motor deterioration. Therefore, our findings may have potential implications for a medication intervention that could prevent potential deleterious side effects and improve health-related quality of life in this frail population.

Role of the neuropathology of Alzheimer disease in dementia in the oldest-old.

BACKGROUND: Neuritic plaques (NPs) and neurofibrillary tangles (NFTs) in the brain, especially in the hippocampus, entorhinal cortex, and isocortex, are hallmark lesions of Alzheimer disease and dementia in the elderly. However, this association has not been extensively studied in the rapidly growing population of the very old. OBJECTIVE: To assess the relationship between estimates of cognitive function and NP and NFT pathologic conditions in 317 autopsied persons aged 60 to 107 years. DESIGN: We studied the relationship between severity of dementia and the density of these characteristic lesions of Alzheimer disease in young-old, middle-old, and oldest-old persons. The relationship of the severity of dementia as measured by the Clinical Dementia Rating scale to the density of NPs and NFTs was then assessed in each age group. PARTICIPANTS: Three hundred seventeen brains of persons aged 60 years and older were selected to have either no remarkable neuropathological lesions or only NP and NFT lesions. Brains with any other neuropathological conditions, either alone or in addition to Alzheimer disease findings, were excluded. The study cohort was then stratified into the youngest quartile (aged 60-80 years), middle 2 quartiles (aged 81-89 years), and oldest quartile (aged 90-107 years). RESULTS: While the density of NPs and NFTs rose significantly by more than 10-fold as a function of the severity of dementia in the youngest-old group, significant increases in the densities of NPs and NFTs were absent in the brains of the oldest-old. This lack of difference in the densities of NPs and NFTs was due to reduced lesion densities in the brains of oldest-old persons with dementia rather than to increased density of these lesions in the brains of nondemented oldest-old persons. CONCLUSIONS: These findings suggest that the neuropathological features of dementia in the oldest-old are not the same as those of cognitively impaired younger-old persons and compel a vigorous search for neuropathological indices of dementia in this most rapidly growing segment of the elderly population.

Prevalence of movement disorders in an elderly nursing home population.

We studied the prevalence of movement disorders in a large nursing home population (397 patients, mean age 86 years) in New York City. Patients were first evaluated by specially trained research coordinators and final clinical diagnoses were confirmed by a movement disorder specialist. A movement disorder was identified in 21% of patients (83/397). The most frequent movement disorders were essential tremor (ET) (8.8%) and parkinsonism (7.1%). Only half of those admitted with a diagnosis of parkinsonism were confirmed in their diagnosis by the movement disorder specialists. Three percent of patients exhibited drug-induced tremor, 1.3% had dystonia, 0.5% had myoclonus and 0.3% had generalized dyskinesias. Overall, our findings underline the high frequency of movement disorders in a nursing home population. The discrepancy between our findings and the prevalence rates for parkinsonism reported on the initial transfer diagnosis emphasizes the difficulty of accurate diagnosis of movement disorders and in particular parkinsonism.

Alzheimer's disease: overview of research and clinical advances.

Since its discovery in the early 1900's, Alzheimer's disease has continued to challenge the medical community. In this article, Dr. Libow presents an overview of the condition, and discusses such topics as prevalence, unmet needs in clinical research, possible causes, behavioral manifestations, and alternative treatments.