Cindy Zadikoff

Toronto Western Hospital, Toronto, Ontario, Canada

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Publications (30)128.92 Total impact

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    ABSTRACT: No conventional treatment has been convincingly demonstrated to slow or stop the progression of Parkinson's disease (PD). Dopaminergic therapy is the gold standard for managing the motor disability associated with PD, but it falls short of managing all of the aspects of the disease that contribute to quality of life. Perhaps for this reason, an increasing number of patients are searching for a more holistic approach to healthcare. This is not to say that they are abandoning the standard and effective symptomatic therapies for PD, but rather are complementing them with healthy living, mind-body practices, and natural products that empower patients to be active participants in their healthcare and widen the net under which disease modification might one day be achieved. Despite high rates of utilization of complementary and alternative medicine (CAM) practices, data on efficacy is generally limited, restricting physicians in providing guidance to interested patients. Exercise is now well-established as integral in the management of PD, but mind-body interventions such as Tai Chi that incorporate relaxation and mindfulness with physical activity should be routinely encouraged as well. While no comment can be made about neuroplastic or disease-modifying effects of mind-body interventions, patients should be encouraged to be as active as possible and engage with others in enjoyable and challenging activities such as dance, music therapy, and yoga. Many PD patients also choose to try herbs, vitamins, and neutraceuticals as part of a healthy lifestyle, with the added expectation that these products may lower free radical damage and protect them against further cell death. Evidence for neuroprotection is limited, but patients can be encouraged to maintain a healthy diet rich in "high-power," low-inflammatory foods, while at the same time receiving education that many promising natural products have produced disappointing results in clinical trials. It is vital that the science of holistic medicine reaches a point where all neutraceuticals are investigated with the same rigor as conventional drugs. A number of agents discussed here that have a proposed role in the treatment of neurodegenerative diseases (and PD in particular), including cannabis, mucuna pruriens, and Chinese herbals, deserve more attention from basic science researchers and clinical investigators before they can be either safely utilized or dismissed.
    Current Treatment Options in Neurology 10/2014; 16(10):314. · 1.94 Impact Factor
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    ABSTRACT: IMPORTANCE Coenzyme Q10 (CoQ10), an antioxidant that supports mitochondrial function, has been shown in preclinical Parkinson disease (PD) models to reduce the loss of dopamine neurons, and was safe and well tolerated in early-phase human studies. A previous phase II study suggested possible clinical benefit. OBJECTIVE To examine whether CoQ10 could slow disease progression in early PD. DESIGN, SETTING, AND PARTICIPANTS A phase III randomized, placebo-controlled, double-blind clinical trial at 67 North American sites consisting of participants 30 years of age or older who received a diagnosis of PD within 5 years and who had the following inclusion criteria: the presence of a rest tremor, bradykinesia, and rigidity; a modified Hoehn and Yahr stage of 2.5 or less; and no anticipated need for dopaminergic therapy within 3 months. Exclusion criteria included the use of any PD medication within 60 days, the use of any symptomatic PD medication for more than 90 days, atypical or drug-induced parkinsonism, a Unified Parkinson's Disease Rating Scale (UPDRS) rest tremor score of 3 or greater for any limb, a Mini-Mental State Examination score of 25 or less, a history of stroke, the use of certain supplements, and substantial recent exposure to CoQ10. Of 696 participants screened, 78 were found to be ineligible, and 18 declined participation. INTERVENTIONS The remaining 600 participants were randomly assigned to receive placebo, 1200 mg/d of CoQ10, or 2400 mg/d of CoQ10; all participants received 1200 IU/d of vitamin E. MAIN OUTCOMES AND MEASURES Participants were observed for 16 months or until a disability requiring dopaminergic treatment. The prospectively defined primary outcome measure was the change in total UPDRS score (Parts I-III) from baseline to final visit. The study was powered to detect a 3-point difference between an active treatment and placebo. RESULTS The baseline characteristics of the participants were well balanced, the mean age was 62.5 years, 66% of participants were male, and the mean baseline total UPDRS score was 22.7. A total of 267 participants required treatment (94 received placebo, 87 received 1200 mg/d of CoQ10, and 86 received 2400 mg/d of CoQ10), and 65 participants (29 who received placebo, 19 who received 1200 mg/d of CoQ10, and 17 who received 2400 mg/d of CoQ10) withdrew prematurely. Treatments were well tolerated with no safety concerns. The study was terminated after a prespecified futility criterion was reached. At study termination, both active treatment groups showed slight adverse trends relative to placebo. Adjusted mean changes (worsening) in total UPDRS scores from baseline to final visit were 6.9 points (placebo), 7.5 points (1200 mg/d of CoQ10; P = .49 relative to placebo), and 8.0 points (2400 mg/d of CoQ10; P = .21 relative to placebo). CONCLUSIONS AND RELEVANCE Coenzyme Q10 was safe and well tolerated in this population, but showed no evidence of clinical benefit. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00740714.
    JAMA Neurology 03/2014; 71(5):543-552. · 7.58 Impact Factor
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    ABSTRACT: IMPORTANCE Diurnal fluctuations of motor and nonmotor symptoms and a high prevalence of sleep-wake disturbances in Parkinson disease (PD) suggest a role of the circadian system in the modulation of these symptoms. However, surprisingly little is known regarding circadian function in PD and whether circadian dysfunction is involved in the development of sleep-wake disturbances in PD. OBJECTIVE To determine the relationship between the timing and amplitude of the 24-hour melatonin rhythm, a marker of endogenous circadian rhythmicity, with self-reported sleep quality, the severity of daytime sleepiness, and disease metrics. DESIGN, SETTING, AND PARTICIPANTS A cross-sectional study from January 1, 2009, through December 31, 2012, of 20 patients with PD receiving stable dopaminergic therapy and 15 age-matched control participants. Both groups underwent blood sampling for the measurement of serum melatonin levels at 30-minute intervals for 24 hours under modified constant routine conditions at the Parkinson's Disease and Movement Disorders Center of Northwestern University. INTERVENTIONS Twenty-four hour monitoring of serum melatonin secretion. MAIN OUTCOMES AND MEASURES Clinical and demographic data, self-reported measures of sleep quality (Pittsburgh Sleep Quality Index) and daytime sleepiness (Epworth Sleepiness Scale), and circadian markers of the melatonin rhythm, including the amplitude, area under the curve (AUC), and phase of the 24-hour rhythm. RESULTS Patients with PD had blunted circadian rhythms of melatonin secretion compared with controls; the amplitude of the melatonin rhythm and the 24-hour AUC for circulating melatonin levels were significantly lower in PD patients (P < .001). Markers of the circadian phase were not significantly different between the 2 groups. Compared with PD patients without excessive daytime sleepiness, patients with excessive daytime sleepiness (Epworth Sleepiness Scale score ≥10) had a significantly lower amplitude of the melatonin rhythm and 24-hour melatonin AUC (P = .001). Disease duration, Unified Parkinson's Disease Rating Scale scores, levodopa equivalent dose, and global Pittsburgh Sleep Quality Index score in the PD group were not significantly related to measures of the melatonin circadian rhythm. CONCLUSIONS AND RELEVANCE Circadian dysfunction may underlie excessive sleepiness in PD. The nature of this association needs to be explored further in longitudinal studies. Approaches aimed to strengthen circadian function, such as timed exposure to bright light and exercise, might serve as complementary therapies for the nonmotor manifestations of PD.
    JAMA neurology. 02/2014;
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    ABSTRACT: Matrix metalloproteinases (MMPs) have been implicated in human immunodeficiency virus (HIV)-associated neurological injury; however, this relationship has not been studied early in infection. Plasma levels of MMP-1, MMP-2, MMP-7, MMP-9, and MMP-10 measured using Luminex technology (Austin, TX, USA) were compared in 52 HIV and 21 seronegative participants of the Chicago Early HIV Infection study. MMP levels were also examined in HIV subgroups defined by antibody reactivity, viremia, and antiretroviral status, as well as in available cerebrospinal fluid (CSF) samples (n = 9). MMPs were evaluated for patterns of relationship to cognitive function and to quantitative magnetic resonance measurements of the brain derived in vivo. Plasma MMP-2 levels were significantly reduced in early HIV infection and correlated with altered white matter integrity and atrophic brain changes. MMP-9 levels were higher in the treated subgroup than in the naïve HIV subgroup. Only MMP-2 and MMP-9 were detected in the CSF; CSF MMP-2 correlated with white matter integrity and with volumetric changes in basal ganglia. Relationships with cognitive function were also identified. MMP-2 levels in plasma and in CSF correspond to early changes in brain structure and function. These findings establish a link between MMPs and neurological status previously unidentified in early HIV infection.
    Journal of NeuroVirology 08/2013; · 2.85 Impact Factor
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    ABSTRACT: External pacing cues, dopaminergic medication, and bilateral subthalamic nucleus deep brain stimulation (STN-DBS) improve repetitive movements performed at low rates. When the pacing rate is increased to frequencies near 2Hz and above, both external pacing cues and Parkinson's medication were shown to be ineffective at improving repetitive finger movement performance. It remains unclear if STN-DBS improves the performance of repetitive finger movements at high pacing rates. This study examined the effects of STN-DBS on the amplitude and rate of repetitive finger movement across a range of external pacing rates. Nine participants with STN-DBS (OFF and ON stimulation) and nine matched healthy adults performed repetitive index finger flexion movements paced by an acoustic tone that increased from 1.0 to 3.0Hz. OFF stimulation, most subjects moved at rates that were substantially higher (hastening pattern) or lower (bradykinesia pattern) than the tone rate, particularly at high pacing rates. ON stimulation, movement rate improved in subjects with the bradykinesia pattern, but not in those with the hastening pattern. Overall, STN-DBS did not significantly affect movement rate. In contrast, STN-DBS significantly (p<0.05) improved movement amplitude across all pacing rates. These findings demonstrate that STN-DBS improves movement amplitude, but had no effect on the rate of movement in participants with a hastening pattern. Separately testing movement amplitude and movement rate using both high and low rate externally paced cues in the clinical environment may aid in the diagnosis and treatment of people with Parkinson's disease.
    Neuroscience Letters 08/2013; · 2.03 Impact Factor
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    ABSTRACT: Background/Aims: To assess the impact of mild cognitive impairment (MCI) or cognitive decline on health-related quality of life (HR-QOL) in Parkinson's disease (PD). Methods: HR-QOL measured by the Parkinson Disease Quality of Life Questionnaire (PDQ-39), MCI according to Movement Disorder Society Task Force criteria and cognitive decline from premorbid baseline were assessed in non-demented PD patients at 6 movement disorder clinics. Results: Among 137 patients, after adjusting for education, gender, disease duration, and Movement Disorder Society Unified Parkinson's Disease Rating Scale total score, MCI was associated with worse scores within the PDQ-39 dimension of communication (p = 0.008). Subjects were divided into tertiles of cognitive decline from premorbid level. Scores in the dimension of stigma were worst in the second tertile of cognitive decline (p = 0.03). MCI was associated with worse social support scores in the second tertile of cognitive decline (p = 0.008). Conclusion: MCI and cognitive decline from premorbid baseline are associated with reduced HR-QOL in communication, stigma, and social support domains. The cognitive decline from premorbid baseline modifies the association between MCI and HR-QOL in PD and knowing both will allow a better appreciation of difficulties patients face in daily life.
    Dementia and Geriatric Cognitive Disorders 06/2013; 36(1-2):67-75. · 2.79 Impact Factor
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    ABSTRACT: Objective: Implicit skill learning is hypothesized to depend on nondeclarative memory that operates independent of the medial temporal lobe (MTL) memory system and instead depends on cortico striatal circuits between the basal ganglia and cortical areas supporting motor function and planning. Research with the Serial Reaction Time (SRT) task suggests that patients with memory disorders due to MTL damage exhibit normal implicit sequence learning. However, reports of intact learning rely on observations of no group differences, leading to speculation as to whether implicit sequence learning is fully intact in these patients. Patients with Parkinson's disease (PD) often exhibit impaired sequence learning, but this impairment is not universally observed. Method: Implicit perceptual-motor sequence learning was examined using the Serial Interception Sequence Learning (SISL) task in patients with amnestic Mild Cognitive Impairment (MCI; n = 11) and patients with PD (n = 15). Sequence learning in SISL is resistant to explicit learning and individually adapted task difficulty controls for baseline performance differences. Results: Patients with MCI exhibited robust sequence learning, equivalent to healthy older adults (n = 20), supporting the hypothesis that the MTL does not contribute to learning in this task. In contrast, the majority of patients with PD exhibited no sequence-specific learning in spite of matched overall task performance. Two patients with PD exhibited performance indicative of an explicit compensatory strategy suggesting that impaired implicit learning may lead to greater reliance on explicit memory in some individuals. Conclusion: The differences in learning between patient groups provides strong evidence in favor of implicit sequence learning depending solely on intact basal ganglia function with no contribution from the MTL memory system. (PsycINFO Database Record (c) 2013 APA, all rights reserved).
    Neuropsychology 05/2013; 27(3):314-321. · 3.58 Impact Factor
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    ABSTRACT: We examined the frequency of Parkinson disease with mild cognitive impairment (PD-MCI) and its subtypes and the accuracy of 3 cognitive scales for detecting PD-MCI using the new criteria for PD-MCI proposed by the Movement Disorders Society. Nondemented patients with Parkinson's disease completed a clinical visit with the 3 screening tests followed 1 to 3 weeks later by neuropsychological testing. Of 139 patients, 46 met Level 2 Task Force criteria for PD-MCI when impaired performance was based on comparisons with normative scores. Forty-two patients (93%) had multi-domain MCI. At the lowest cutoff levels that provided at least 80% sensitivity, specificity was 44% for the Montreal Cognitive Assessment and 33% for the Scales for Outcomes in Parkinson's Disease-Cognition. The Mini-Mental State Examination could not achieve 80% sensitivity at any cutoff score. At the highest cutoff levels that provided specificity of at least 80%, sensitivities were low (≤44%) for all tests. When decline from estimated premorbid levels was considered evidence of cognitive impairment, 110 of 139 patients were classified with PD-MCI, and 103 (94%) had multi-domain MCI. We observed dramatic differences in the proportion of patients who had PD-MCI using the new Level 2 criteria, depending on whether or not decline from premorbid level of intellectual function was considered. Recommendations for methods of operationalizing decline from premorbid levels constitute an unmet need. Among the 3 screening tests examined, none of the instruments provided good combined sensitivity and specificity for PD-MCI. Other tests recommended by the Task Force Level 1 criteria may represent better choices, and these should be the subject of future research. © 2013 Movement Disorder Society.
    Movement Disorders 03/2013; · 5.63 Impact Factor
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    ABSTRACT: BACKGROUND: Freezing of gait (FOG) is a common symptom in patients with advanced Parkinson's disease (PD) representing a major cause of disability and falls. Although the pathophysiology of FOG remains poorly understood, nondopaminergic pathways have been implicated. Treatment studies of levodopa and selegiline have shown limited benefit for FOG. Limited data suggest that amantadine, an N-methyl-D-aspartate receptor antagonist, may be beneficial for FOG in PD. OBJECTIVE: To examine the relationship between treatment with oral amantadine and FOG in patients with PD. METHODS: We conducted a retrospective chart review of PD patients who received amantadine specifically for FOG and had a follow-up assessment of FOG. The primary outcome measure was self-reported effectiveness of amantadine (improvement, worsening, or no change in FOG) based on records from the follow-up assessment. RESULTS: Eleven patients with PD with median age of PD onset of 67 years (range, 51-84 years) and median Hoehn and Yahr stage 3 (range, 2-4) met the study population selection criteria. Ten of 11 patients reported improvement in FOG after initiation of amantadine, whereas FOG worsened in one patient. Median amantadine dosage was 100 mg twice daily, and treatment duration was 20 months (range, 6-66 months). Four patients reported reduction in benefit after 4 months. Three patients reported adverse effects, including blurred vision, visual hallucinations, and peripheral edema; the latter 2 effects resulted in discontinuation of amantadine. CONCLUSION: Amantadine is associated with self-reported improvement in FOG in PD, but this effect may be transient. Further studies, including a randomized placebo-controlled trial, are needed to better evaluate this association.
    Clinical neuropharmacology 11/2012; · 2.35 Impact Factor
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    Parkinsonism & Related Disorders 10/2012; · 3.27 Impact Factor
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    ABSTRACT: Pedunculopontine nucleus (PPN) DBS has emerged as a potential intervention for patients with gait and balance disorders. However, targeting this nucleus can be challenging. We report on the first neuropathological analyses after PPN-DBS surgery in advanced progressive supranuclear palsy (PSP). Two patients with PSP underwent unilateral PPN-DBS surgery and were clinically followed to autopsy. Both patients underwent postmortem neuropathological analysis, including choline acetyltransferase immunohistochemistry, to ascertain PPN boundaries and electrode location. Both patients experienced partial improvement in some motor and nonmotor domains postintervention, but died shortly of other complications. Postmortem neuropathological analysis of each patient confirmed the electrode in a region of cholinergic neuronal loss corresponding to the PPN. We provide histopathological evidence for the validity of our stereotactic approach to target the PPN and correlate electrode location with clinical outcomes. © 2012 Movement Disorder Society.
    Movement Disorders 08/2012; 27(10):1304-7. · 5.63 Impact Factor
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    ABSTRACT: We assessed the Pill Questionnaire as a screen for mild cognitive impairment in nondemented Parkinson's disease patients. The relationship between ability to remember medications for Parkinson's disease in the Pill Questionnaire, mild cognitive impairment, and deficits on neuropsychological tests performed 2-3 weeks later blind to Pill Questionnaire results was assessed in movement disorders clinic patients. In 109 subjects, inaccurate medication reporting on the Pill Questionnaire was associated with lower scores on the Montreal Cognitive Assessment, Scales for Outcomes in Parkinson's Disease-Cognition and with deficits in memory, attention, executive function-inhibitory control, processing speed, visuospatial function, and language. Inaccurate medication reporting was also associated with an adjusted odds ratio of 2.4 (95% CI, 0.91-5.88; P = .06) for mild cognitive impairment, with a specificity of 80% and sensitivity of 41%. The Pill Questionnaire is neither sensitive nor specific enough to be used as the sole screening or diagnostic tool for mild cognitive impairment. However, inaccurate medication reporting is associated with deficits spanning many cognitive domains and should alert a clinician to a higher likelihood of cognitive impairment. © 2012 Movement Disorder Society.
    Movement Disorders 08/2012; 27(10):1308-11. · 5.63 Impact Factor
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    ABSTRACT: The role of cognitive reserve in Parkinson's disease (PD)-mild cognitive impairment (MCI) is incompletely understood. The relationships between PD-MCI, years of education, and estimated premorbid IQ were examined in 119 consecutive non-demented PD patients using logistic regression models. Higher education and IQ were associated with reduced odds of PD-MCI in univariate analysis. In multivariable analysis, a higher IQ was associated with a significantly decreased odds of PD-MCI, but education was not. The association of higher IQ and decreased odds of PD-MCI supports a role for cognitive reserve in PD, but further studies are needed to clarify the interaction of IQ and education and the impact of other contributors such as employment and hobbies.
    Dementia and geriatric cognitive disorders extra. 01/2012; 2(1):343-52.
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    ABSTRACT: Background Dystonia may result from reduced GABAergic transmission in the external globus pallidus (GPe). Cannabinoid CB1 agonists enhance GABA in the GPe and may therefore reduce dystonia.Objectives To determine the efficacy of the cannabinoid CB1 agonist, dronabinol, in cervical dystonia (CD).Methods Nine patients with CD were randomised to dronabinol (15 mg/d)/placebo in an 8-week crossover trial. Outcome measures included TWSTRS, visual analog scale of pain, global impression of change and adverse events (AEs).ResultsThere was no effect of dronabinol compared to placebo on any outcome measure (all P > 0.05, n = 7). One subject withdrew due to AEs and one was lost to follow-up. Mild AEs were experienced by all.Conclusions Short–term use of dronabinol in CD has no benefit. Despite the study limitations, cannabinoids are unlikely to be useful in the treatment of dystonia.
    Basal Ganglia. 07/2011; 1(2):91–95.
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    ABSTRACT: A 30-item self-completed survey was administered to 216 consecutive patients with various movement disorders in order to assess their knowledge base, perceptions, and beliefs about brain donation. Two hundred three surveys were analyzed. While 78% of study participants did not know about brain donation before completing the survey, 56% would be willing to consider brain donation. Willingness to consider brain donation is not significantly different between genders, or influenced by the degree of religious involvement, marital status, or disease duration. Majority of the study participants consider discussions about brain donation appropriate during regular clinic visits. Younger participants were more likely to consider brain donation. Major motivating factors to pursue brain donation were advancement of medical knowledge, providing hope and purpose for others, and advancing our understanding of hereditability of a disorder that may impact surviving family members. We advocate proactive education of patients with various movement disorders about the purpose and benefits of brain donation.
    Parkinsonism & Related Disorders 03/2011; 17(3):204-7. · 3.27 Impact Factor
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    ABSTRACT: Recent data suggests that isradipine, a dihydropyridine calcium channel blocker, is neuroprotective in preclinical models of parkinsonism. Isradipine has not been systematically studied in patients with Parkinson's disease (PD). The aim of this study was to evaluate safety and tolerability of isradipine controlled release (CR) in patients with early PD. Qualified subjects (n = 31) received isradipine CR, titrated from 5 to 20 mg daily dose over 8 weeks as tolerated. Eighty-one percent of subjects completed the study. Tolerability of isradipine CR was dose dependent: 94% for 5 mg dose; 87% for 10 mg; 68% for 15 mg; and 52% for 20 mg. Isradipine had no significant effect on blood pressure or PD motor disability. The two most common reasons for dose reduction were leg edema (7) and dizziness (3). There was no difference in isradipine tolerability between subjects with and without dopaminergic treatment, or with and without hypertension.
    Movement Disorders 12/2010; 25(16):2863-6. · 5.63 Impact Factor
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    ABSTRACT: Currently, electroencephalography (EEG) cannot be used to record cortical activity during clinically effective DBS due to the presence of large stimulation artifact with components that overlap the useful spectrum of the EEG. A filtering method is presented that removes these artifacts whilst preserving the spectral and temporal fidelity of the underlying EEG. The filter is based on the Hampel identifier that treats artifacts as outliers in the frequency domain and replaces them with interpolated values. Performance of the filter was tested with a synthesized DBS signal and actual data recorded during bilateral monopolar DBS. Mean increases in signal-to-noise ratio of 7.8dB for single-frequency stimulation and 13.8dB for dual-frequency stimulation are reported. Correlation analysis between EEG with synthesized artifacts and artifact-free EEG reveals that distortion to the underlying EEG in the filtered signal is negligible (r(2)>0.99). Frequency-domain Hampel filtering has been shown to remove monopolar DBS artifacts under a number of common stimulation conditions used for the treatment of Parkinson's disease. Application of frequency-domain Hampel filtering will allow the measurement of EEG in patients during clinically effective DBS and thus may increase our understanding of the mechanisms of action of this important therapeutic intervention.
    Clinical neurophysiology: official journal of the International Federation of Clinical Neurophysiology 03/2010; 121(8):1227-32. · 3.12 Impact Factor
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    ABSTRACT: Pergolide is an ergot derived dopamine agonist that is widely used for the treatment of Parkinson's disease. Studies have found an association between pergolide and valvular heart abnormalities although there is still much to be learned about the clinical significance of the valvular changes, who is at risk, and whether there is duration of exposure effect. To assess the long term risk of hospital admissions for valvular heart disease (VHD) or congestive heart failure (CHF, a clinically overt outcome of VHD) in new users of pergolide compared to new users of levodopa. The secondary objective was to assess whether there are any characteristics that can predict who is at higher risk of developing this outcome. Retrospective, population-based cohort study. Setting: Ontario, Canada. Ontario residents aged 66 and older, newly started on treatment with either pergolide or levodopa. Outcomes: Admission to hospital with the most responsible diagnosis of congestive heart failure or valvular heart disease. The risk for admission for valvular heart disease or congestive heart failure were higher in those with 1-4 years exposure to pergolide compared with no exposure to pergolide (VHD: hazard ratio 2.4, p = 0.04; CHF: hazard ratio 1.6, p = 0.02). No such pattern was found with exposure to levodopa. Our study demonstrates that treatment with pergolide is associated with a higher risk of hospital admission for valvular heart disease or congestive heart failure and that this risk is greater in those with 1-4 years exposure than in those with less exposure. We did not find an increased risk beyond four years.
    The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques 06/2008; 35(2):173-8. · 1.33 Impact Factor
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    ABSTRACT: Deep brain stimulation of the globus pallidus internus has been used for the treatment of various forms of dystonia, but the factors influencing postoperative outcomes remain unknown. We compared the location of the contacts being used for stimulation (active contacts) in patients with cervical dystonia, generalized dystonia, and Parkinson's disease and correlated the results with clinical outcome. Postoperative magnetic resonance scans of 13 patients with cervical dystonia, six patients with generalized dystonia, and five patients with Parkinson's disease who underwent globus pallidus internus deep brain stimulation were analyzed. We assessed the location of the active contacts relative to the midcommisural point and in relation to the anteroposterior and mediolateral boundaries of the pallidum. Postoperative outcome was measured with the Toronto Western Spasmodic Torticollis Rating Scale (for cervical dystonia) and the Burke-Fahn-Marsden Dystonia Rating Scale (for generalized dystonia) during the last follow-up. We found that the location of the active contacts relative to the midcommisural point and the internal boundaries of the pallidum was similar across the groups. In our series, the contacts used for stimulation were clustered in the posterolateral region of the pallidum. Within that region, we found no correlation between the location of the contacts and postoperative outcome. The location of the active contacts used for globus pallidus internus deep brain stimulation was similar in patients with cervical dystonia, generalized dystonia, and Parkinson's disease.
    Neurosurgery 04/2008; 62(3 Suppl 1):217-23; discussion 223-5. · 2.53 Impact Factor
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    ABSTRACT: Dementia is an important and increasingly recognized problem in Parkinson's disease (PD). The mini-mental state examination (MMSE) often fails to detect early cognitive decline. The Montreal cognitive assessment (MoCA) is a brief tool developed to detect mild cognitive impairment that assesses a broader range of domains frequently affected in PD. The scores on the MMSE and the MoCA were compared in 88 patients with PD. A pronounced ceiling effect was observed with the MMSE but not with the MoCA. The range and standard deviation of scores was larger with the MoCA(7-30, 4.26) than with the MMSE(16-30, 2.55). The percentage of subjects scoring below a cutoff of 26/30 (used by others to detect mild cognitive impairment) was higher on the MoCA (32%) than on the MMSE (11%) (P < 0.000002). Compared to the MMSE, the MoCA may be a more sensitive tool to identify early cognitive impairment in PD.
    Movement Disorders 02/2008; 23(2):297-9. · 5.63 Impact Factor

Publication Stats

338 Citations
128.92 Total Impact Points

Institutions

  • 2005–2013
    • Toronto Western Hospital
      Toronto, Ontario, Canada
  • 2007–2008
    • Northwestern University
      • • Parkinson's Disease and Movement Disorders Center
      • • Division of Hospital Medicine
      Evanston, IL, United States