Determining the impact of specialized care on health outcomes and health care utilization in Parkinsonism.

BACKGROUND: Although care of Parkinsonism (PKM) is assumed to be optimally provided by movement disorder neurologists within an interdisciplinary clinic model, there is a paucity of published data to support this. OBJECTIVES: To investigate the impact of movement disorder neurologist care of individuals with Parkinsonism (PKM). METHODS: A retrospective exposure design was adopted using administrative data. Incident PKM individuals were identified in billing claims. A nine-year exposure period to movement disorder neurologist, general neurologist and non-neurologist care was calculated based on the billing codes. Regression models were used to test the association of provider exposure on time to death and long-term care (LTC) admission. Linear models were used to test varying provider exposure and hospital admissions, hospital days and emergency department visits. RESULTS: 1914 incident individuals were identified. There was no difference in PKM mortality, emergency visits, hospital admissions, or hospital days between providers, however exposure to general neurology and non-neurology care was associated with a significantly higher risk of admission to LTC compared to movement disorder neurologist care (HR 1.43; 95% CI 1.09-1.87 for general neurology (p-value = 0.0089); HR 1.61; 95% CI 1.25-2.05 for non-neurology (p-value = 0.0002), respectively. CONCLUSION: Movement disorder neurologist care is associated with a lower risk of admission to LTC over general neurologist care in individuals with PKM.

Changes in Metabolic Activity and Gait Function by Dual-Task Cognitive Game-Based Treadmill System in Parkinson's Disease: Protocol of a Randomized Controlled Trial.

Balance and gait impairments, and consequently, mobility restrictions and falls are common in Parkinson's disease (PD). Various cognitive deficits are also common in PD and are associated with increased fall risk. These mobility and cognitive deficits are limiting factors in a person's health, ability to perform activities of daily living, and overall quality of life. Community ambulation involves many dual-task (DT) conditions that require processing of several cognitive tasks while managing or reacting to sudden or unexpected balance challenges. DT training programs that can simultaneously target balance, gait, visuomotor, and cognitive functions are important to consider in rehabilitation and promotion of healthy active lives. In the proposed multi-center, randomized controlled trial (RCT), novel behavioral positron emission tomography (PET) brain imaging methods are used to evaluate the molecular basis and neural underpinnings of: (a) the decline of mobility function in PD, specifically, balance, gait, visuomotor, and cognitive function, and (b) the effects of an engaging, game-based DT treadmill walking program on mobility and cognitive functions. Both the interactive cognitive game tasks and treadmill walking require continuous visual attention, and share spatial processing functions, notably to minimize any balance disturbance or gait deviation/stumble. The ability to "walk and talk" normally includes activation of specific regions of the prefrontal cortex (PFC) and the basal ganglia (site of degeneration in PD). The PET imaging analysis and comparison with healthy age-matched controls will allow us to identify areas of abnormal, reduced activity levels, as well as areas of excessive activity (increased attentional resources) during DT-walking. We will then be able to identify areas of brain plasticity associated with improvements in mobility functions (balance, gait, and cognition) after intervention. We expect the gait-cognitive training effect to involve re-organization of PFC activity among other, yet to be identified brain regions. The DT mobility-training platform and behavioral PET brain imaging methods are directly applicable to other diseases that affect gait and cognition, e.g., cognitive vascular impairment, Alzheimer's disease, as well as in aging.

Imaging Cerebral Glucose Metabolism during Dual-Task Walking in Patients with Parkinson's disease.

BACKGROUND AND PURPOSE: Gait impairment is a hallmark of Parkinson's disease (PD). Natural walking involves more cognitive demand than treadmill walking or in-laboratory walking tests because patients have to actively work on navigation and top-down cognitive control which taxes cognitive reserve in the prefrontal cortex. To mimic the prefrontal engagement occurring with natural walking in a controlled and safe environment, dual-task (DT) treadmill walking has been developed. In this study, we tested the feasibility of imaging DT walking-related changes in brain glucose metabolism in patients with PD. METHODS: Fifteen patients with PD were scanned with fluorodeoxyglucose (FDG) positron emission tomography. Five patients performed DT walking, and 10 patients were rested during the FDG uptake period. First, the images were contrasted between the groups. Second, the walking-related brain glucose metabolism was inspected at the individual level. RESULTS: Consistently increased glucose metabolism was identified in DT walking versus rest in the primary visual/sensorimotor areas, thalamus, superior colliculus, and cerebellum. In individual level analysis, patients with less progressed disease (n = 3) showed prefrontal activity during DT walking while patients with more progressed disease (n = 2) did not. CONCLUSION: This study confirms the feasibility of imaging glucose metabolism during DT walking in patients with PD. We also report that during DT walking, there is a lesser degree of prefrontal engagement in the patients with more progressed disease compared to those with less progressed disease, implying increased degrees of frontal dysfunction with PD progression.

Elevated caudate connectivity in cognitively normal Parkinson's disease patients.

Mild cognitive impairment (MCI) is common in Parkinson's disease patients. However, its underlying mechanism is not well understood, which has hindered new treatment discoveries specific to MCI. The aim of this study was to investigate functional connectivity changes of the caudate nucleus in cognitively impaired Parkinson's patients. We recruited 18 Parkinson's disease patients-10 PDNC [normal cognition Parkinson's disease; Montreal Cognitive Assessment (MoCA) ≥ 26], 8 PDLC (low cognition Parkinson's disease; MoCA < 26) -and 10 age-matched healthy controls. All subjects were scanned with resting-state functional magnetic resonance imaging (MRI) and perfusion MRI. We analyzed these data for graph theory metrics and Alzheimer's disease-like pattern score, respectively. A strong positive correlation was found between the functional connectivity of the right caudate nucleus and MoCA scores in Parkinson's patient groups, but not in healthy control subjects. Interestingly, PDNC's functional connectivity of the right caudate was significantly higher than both PDLC and healthy controls, while PDLC and healthy controls were not significantly different from each other. We found that Alzheimer's disease-like metabolic/perfusion pattern score correlated with MoCA scores in healthy controls, but not in Parkinson's disease. Increased caudate connectivity may be related to a compensatory mechanism found in cognitively normal patients with Parkinson's disease. Our findings support and complement the dual syndrome hypothesis.

Blood Flow and Glucose Metabolism Dissociation in the Putamen Is Predictive of Levodopa Induced Dyskinesia in Parkinson's Disease Patients.

Background: The forefront treatment of Parkinson's disease (PD) is Levodopa. When patients are treated with Levodopa cerebral blood flow is increased while cerebral metabolic rate is decreased in key subcortical regions including the putamen. This phenomenon is especially pronounced in patients with Levodopa-induced dyskinesia (LID). Method: To study the effect of clinically-determined anti-parkinsonian medications, 10 PD patients (5 with LID and 5 without LID) have been scanned with FDG-PET (a probe for glucose metabolism) and perfusion MRI (a probe for cerebral blood flow) both when they are ON and OFF medications. Patients additionally underwent resting state fMRI to detect changes in dopamine-mediated cortico-striatal connectivity. The degree of blood flow-glucose metabolism dissociation was quantified by comparing the FDG-PET and perfusion MRI data. Results: A significant interaction effect (imaging modality × medication; blood flow-glucose metabolism dissociation) has been found in the putamen (p = 0.023). Post-hoc analysis revealed that anti-parkinsonian medication consistently normalized the pathologically hyper-metabolic state of the putamen while mixed effects were observed in cerebral blood flow changes. This dissociation was especially predominant in patients with LID compared to those without. Unlike the prior study, this differentiation was not observed when cortico-striatal functional connectivity was assessed. Conclusion: We confirmed striatal neurovascular dissociation between FDG-PET and perfusion MRI in response to clinically determined anti-parkinsonian medication. We further proposed a novel analytical method to quantify the degree of dissociation in the putamen using only the ON condition scans, Putamen-to-thalamus Hyper-perfusion/hypo-metabolism Index (PHI), which may have the potential to be used as a biomarker for LID (correctly classifying 8 out 10 patients). For wider use of PHI, a larger validation study is warranted.

Educational Needs and Considerations for a Visual Educational Tool to Discuss Parkinson's Disease.

BACKGROUND: In our clinical experience, people with Parkinson's disease (PwP) and their caregivers have difficulty understanding the complexities of the disease, which has a multitude of symptoms and involved therapies. We undertook a needs assessment to understand the need for, and to guide the development of, an educational tool. METHODS: We invited PwP, caregivers and health care providers (HCP) from across Canada to participate in an online survey to determine the need and desired content for such a tool. RESULTS: Respondents included 450 PwP, 335 caregivers, and 96 HCP from across Canada. 86.5% of HCP reported that it was "very important" for patients to understand issues in PD and 84.4% would use a visual aid to explain these issues. Results showed that 81.9-95.7% of caregivers and PwP were not "very satisfied" with the explanations of all domains in PD. Non-motor symptoms and cognitive issues were highly ranked by all groups as difficult to understand or explain. Older PwP (those with PD for less than 5 years and those who reported that their HCP spent less than 15 minutes counselling in each clinic visit) were less likely to fully understand and be satisfied with the explanations of most issues in PD. INTERPRETATION: There is a need for better patient education when discussing PD issues in the clinical setting. Older PwP that have been recently diagnosed have the greatest educational needs. Potential users indicate that a visual aid would help and non-motor symptoms, particularly cognitive issues, need to be a focus of such a tool.

Distinct brain metabolic patterns separately associated with cognition, motor function, and aging in Parkinson's disease dementia.

We explored whether patients with Parkinson's disease dementia (PDD) show a distinct spatial metabolic pattern that characterizes cognitive deficits in addition to motor dysfunction. Eighteen patients with PDD underwent 3 separate positron emission tomography sessions with [18F]fluorodeoxyglucose (for glucose metabolism), fluorinated N-3-fluoropropyl-2-beta-carboxymethoxy-3-beta-(4-iodophenyl) nortropane (for dopamine transporter density) and Pittsburgh compound-B (for beta-amyloid load). We confirmed in PDD versus normal controls, overall hypometabolism in the posterior and prefrontal brain regions accompanied with hypermetabolism in subcortical structures and the cerebellar vermis. A multivariate network analysis then revealed 3 metabolic patterns that are separately associated with cognitive performance (p = 0.042), age (p = 0.042), and motor symptom severity (p = 0.039). The age-related pattern's association with aging was replicated in healthy controls (p = 0.047) and patients with Alzheimer's disease (p = 0.002). The cognition-related pattern's association with cognitive performance was observed, with a trend-level of correlation, in patients with dementia with Lewy bodies (p = 0.084) but not in patients with Alzheimer's disease (p = 0.974). We found no association with fluorinated N-3-fluoropropyl-2-beta-carboxymethoxy-3-beta-(4-iodophenyl) nortropane and Pittsburgh compound-B positron emission tomography with patients' cognitive performance.

Healthcare utilization in patients with Parkinson's disease: a population-based analysis.

PURPOSE: To investigate factors associated with healthcare utilization and prescription drug use for Parkinson's disease (PD) patients and matched controls. METHODS: A retrospective matched-group design was adopted using administrative data from Manitoba, Canada. PD cases (N = 1469) were identified from diagnoses in hospital records and physician billing claims and matched to controls (N = 2938) on age, sex, and region of residence. Sixteen measures of healthcare utilization were examined over a six-year period using generalized linear models. RESULTS: PD cases had greater healthcare utilization than controls for almost all investigated services, with the exception of visits to non-neurological specialists and hospital use for non-mental disorder diagnoses. For controls, utilization of all forms of healthcare increased with age; for PD cases the relationship was weak, except for specialist visits, where an inverse relationship was observed. A rural region of residence was associated with a lower rate of seeing a specialist or any medical doctor, with a higher rate of hospitalization than for urban cases or controls. Comorbidity was strongly associated with healthcare use for both groups. Over the six-year study period significant differences in the trend were observed for mental disorder hospitalizations, hospital days, and physician visits. CONCLUSIONS: Factors associated with healthcare utilization in PD patients differ from those without PD. This information may help to identify and optimize healthcare services and associated costs for PD patients.

Asymmetry in parkinsonism, spreading pathogens and the nose.

Parkinson's disease, as well as many other parkinsonisms, including most toxic, neurodegenerative and familial types are typically asymmetric. No explanation for this phenomenon exists. A summary of the frequency of asymmetry in a spectrum of parkinsonian disorders is provided. Evidence against asymmetry being the result of normal asymmetries of the substantia nigrais reviewed. Asymmetry either results from a greater susceptibility on one side or a spreading pathology entering or starting on one side of the CNS. With the increasing evidence for spreading pathologies (toxins, viruses, α-synuclein), knowledge of neuroanatomical connections, and literature implicating spreading pathogens from the enteric and olfactory nerves, potential explanations can be theorized and explored, including the possibility of a pathogen preferentially entering or originating in the olfactory bulb on one side, with subsequent involvement of the other side.

Socioeconomic variations in the prevalence and incidence of Parkinson's disease: a population-based analysis.

BACKGROUND: For many chronic conditions, lower socioeconomic status is associated with higher rates of disease. Previous research has not investigated whether this inverse relationship exists for Parkinson's disease (PD). The purpose was to investigate the association between socioeconomic status and prevalence and incidence of PD. METHODS: The study was conducted using population-based administrative data from Manitoba, Canada. PD cases were identified from diagnoses in hospital and physician records. Area-level census data on average household income and residential postal codes in health insurance registration files were used to assign PD cases to urban and rural income quintiles. Annual adjusted prevalence and incidence estimates were calculated for fiscal years 1987/88-2006/07. Hypotheses about differences between quintiles in average estimates and average rates of change were tested using generalised linear models with generalised estimating equations. RESULTS: The estimated prevalence of PD increased over the 20-year-period but incidence remained unchanged. In urban regions, average prevalence and incidence estimates were significantly higher for the lowest income quintile than the highest quintile. In rural regions, average prevalence estimates were significantly higher for the lowest quintile than for the highest quintile but incidence estimates were not significantly different. The annual rate of increase in the PD prevalence was significantly different for the lowest urban and rural income quintiles. CONCLUSIONS: There is a greater burden of PD in low-income areas. An understanding of socioeconomic inequalities is useful when formulating hypotheses about factors associated with disease onset and developing equity-oriented policies about access to healthcare resources.

Long-term treatment of sleep breathing disorder in a patient with Huntington's disease.

Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder. An association with sleep breathing disorder has not previously been established in the literature. We report the case of a 45-year-old woman with HD, presenting with snoring and observed apnea. Polysomnography showed obstructive sleep apnea with an apnea-hypopnea index (AHI) of 6.6 per hour including events up to 57 s long during rapid eye movement (REM) sleep. A trial of continuous positive airway pressure (CPAP) resulted in significant improvement in sleep structure, nocturnal respiration, daytime alertness, and subjective memory. Snoring, apneas, and respiratory arousals were abolished on CPAP. HD patients may suffer from sleep breathing disorder, and in spite of potential chorea, CPAP is feasible and may significantly improve their quality of life.

Excessive daytime sleepiness and sudden-onset sleep in Parkinson disease: a survey by the Canadian Movement Disorders Group.

CONTEXT: Somnolence is a recognized adverse effect of dopamine agonists. Two new dopamine agonists, pramipexole and ropinirole, have been reported to cause sudden-onset sleep spells in patients with Parkinson disease (PD) while they were driving. The frequency of these spells and whether driving should be restricted has yet to be established. OBJECTIVE: To determine the frequency of and predictors for sudden-onset sleep and, particularly, episodes of falling asleep while driving among patients with PD. DESIGN, SETTING, AND PARTICIPANTS: Prospective survey conducted between January and April 2000 in 18 clinics directed by members of the Canadian Movement Disorders Group; 638 consecutive highly functional PD patients without dementia were enrolled, of whom 420 were currently drivers. MAIN OUTCOME MEASURES: Excessive daytime sleepiness and sudden-onset sleep as assessed by the Epworth Sleepiness Scale and the Inappropriate Sleep Composite Score. The latter score, designed for this study, addressed falling asleep in unusual circumstances. The 2 scales were combined in 3 separate formats: dozing off, sudden unexpected sleep, and sudden blank spells. RESULTS: Excessive daytime sleepiness was present overall in 327 (51%) of the 638 patients and in 213 (51%) of the 420 drivers. Patients taking a variety of different dopamine agonists had no differences in Epworth sleepiness scores, in the composite score, or in the risk of falling asleep while driving. Sixteen patients (3.8%) had experienced at least 1 episode of sudden onset of sleep while driving (after the diagnosis of PD); in 3 (0.7%), it occurred without warning. The 2 risk factors associated with falling asleep at the wheel were the Epworth Sleepiness Scale score (odds ratio [OR], 1.14; 95% confidence interval [CI], 1.06-1.24) and the Inappropriate Sleep Composite Score (OR, 2.54; 95% CI, 1.76-3.66). A standard Epworth Sleepiness Scale score of 7 or higher predicted 75% of episodes of sleep behind the wheel at a specificity of 50% (exclusion of the question related to driving provided 70% sensitivity and 52% specificity), whereas a score of 1 on the Inappropriate Sleep Composite Score generated a sensitivity of 52% and specificity of 82%. CONCLUSIONS: Excessive daytime sleepiness is common even in patients with PD who are independent and do not have dementia. Sudden-onset sleep without warning is infrequent. The Epworth score has adequate sensitivity for predicting prior episodes of falling asleep while driving and its specificity can be increased by use of the Inappropriate Sleep Composite Score. It is unknown if routinely performing these assessments could be more effective in predicting future risk for these rare sleep attacks. Patients should be warned not to drive if they doze in unusual circumstances.