Statin usage, vascular diagnosis and vascular risk factors in Parkinson's disease

Background and aims: Vascular disease is a common comorbidity in Parkinson’s disease patients. Statins are potentially neuroprotective for Parkinson’s disease through non-vascular mechanisms. We investigated prevailing statin use in a Parkinson’s disease cohort. Methods and results: Data on diagnostic indication for statins, anti-Parkinson therapy, vascular risk factors, and statin prescription, were obtained from electronic medical record review for consecutive Parkinson’s disease patients. The ASsessing cardiac risk using Scottish Intercollegiate Guidelines Network system was used to calculate future cardiovascular risk and identify those warranting statin use. Of 441 patients included, 59.9% were male, with a mean age of 68.9 years (standard deviation 10.3). One hundred and seventy-four (39.5%) patients had at least one diagnostic indication for statin use, of whom 136 (78.2%) were prescribed a statin. In the 267 (60.5%) cases without a diagnostic indication, 54 (20.2%) were excluded owing to age limitations defined in ASsessing cardiac risk using Scottish Intercollegiate Guidelines Network. Of the remaining 213, 62 (29.1%) had an ASsessing cardiac risk using Scottish Intercollegiate Guidelines Network score in the recommended range for statin therapy, of whom 15 (24.1%) were prescribed statins. Conclusion: There is suboptimal implementation of statin therapy in Parkinson’s disease patients. Given the possible neuroprotective effects of statins in Parkinson’s disease in addition to reducing cardiovascular risk, reasons for suboptimal implementation warrant further investigation

Switch from abobotulinumtoxinA (Dysport®) to incobotulinumtoxinA (Xeomin®) botulinum toxin formulation: A review of 257 cases

OBJECTIVE: To explore the dose equivalence ratio and treatment costs for abobotulinumtoxinA and incobotulinumtoxinA for patients with focal dystonias. DESIGN: Patient chart review. SUBJECTS/PATIENTS: Adult patients with blepharospasm (n = 19), cervical dystonia (n = 122), hemifacial spasm (n = 91) or segmental/generalized dystonia (n = 19) at a neurology outpatient clinic. METHODS: Patients were switched from established abobotulinumtoxinA therapy to incobotulinumtoxinA at a ~4:1 unit ratio. Dose requirements, injection intervals, treatment efficacy, and adverse events were evaluated for a period of ≥ 1 year. RESULTS: Patients were switched from abobotulinumtoxinA to incobotulinumtoxinA with a mean dose ratio of 4.07 (standard deviation (SD) 0.50). After switching, incobotulinumtoxinA dose requirements remained stable; the mean (SD) dose ratio at the end of the review period (52-219 weeks after switching) was 3.89 (SD 0.58). Injection intervals also remained stable after switching. Adverse events were injection site pain (n = 45) and bruising (n = 4). Five patients (2.0%) discontinued incobotulinumtoxinA treatment: 4 stopped receiving injections, and 1 reverted to abobotulinumtoxinA. Switching to incobotulinumtoxinA reduced the mean toxin expenditure to 76.7% of the cost of abobotulinumtoxinA. CONCLUSION: For patients with conditions commonly treated in dystonia clinics, switching from abobotulinumtoxinA to incobotulinumtoxinA, given at equivalent doses (~4:1 unit ratio) at similar intervals, was effective, well tolerated and achieved cost savings

Neuropathology of dementia in patients with Parkinson’s disease: a systematic review of autopsy studies

Background: Dementia is a common, debilitating feature of late Parkinson’s disease (PD). PD dementia (PDD) is associated with α-synuclein propagation, but coexistent Alzheimer’s disease (AD) pathology may coexist. Other pathologies (cerebrovascular, transactive response DNA-binding protein 43 (TDP-43)) may also influence cognition. We aimed to describe the neuropathology underlying dementia in PD. Methods: Systematic review of autopsy studies published in English involving PD cases with dementia. Comparison groups included PD without dementia, AD, dementia with Lewy bodies (DLB) and healthy controls. Results: 44 reports involving 2002 cases, 57.2% with dementia, met inclusion criteria. While limbic and neocortical α-synuclein pathology had the strongest association with dementia, between a fifth and a third of all PD cases in the largest studies had comorbid AD. In PD cases with dementia, tau pathology was moderate or severe in around a third, and amyloid-β pathology was moderate or severe in over half. Amyloid-β was associated with a more rapid cognitive decline and earlier mortality, and in the striatum, distinguished PDD from DLB. Positive correlations between multiple measures of α-synuclein, tau and amyloid-β were found. Cerebrovascular and TDP-43 pathologies did not generally contribute to dementia in PD. TDP-43 and amyloid angiopathy correlated with coexistent Alzheimer pathology. Conclusions: While significant α-synuclein pathology is the main substrate of dementia in PD, coexistent pathologies are common. In particular, tau and amyloid-β pathologies independently contribute to the development and pattern of cognitive decline in PD. Their presence should be assessed in future clinical trials where dementia is a key outcome measure

Utility of the new Movement Disorder Society clinical diagnostic criteria for Parkinson's disease applied retrospectively in a large cohort study of recent onset cases

Objective: To examine the utility of the new Movement Disorder Society (MDS) diagnostic criteria in a large cohort of Parkinson's disease (PD) patients. Methods: Recently diagnosed (<3.5 years) PD cases fulfilling United Kingdom (UK) brain bank criteria in Tracking Parkinson's, a UK multicenter prospective natural history study were assessed by retrospective application of the MDS criteria. Results: In 2000 cases, 1835 (91.7%) met MDS criteria for PD, either clinically established (n = 1261, 63.1%) or clinically probable (n = 574, 28.7%), leaving 165 (8.3%) not fulfilling criteria. Clinically established cases were significantly more likely to have limb rest tremor (89.3%), a good l-dopa response (79.5%), and olfactory loss (71.1%), than clinically probable cases (60.6%, 44.4%, and 34.5% respectively), but differences between probable PD and ‘not PD’ cases were less evident. In cases not fulfilling criteria, the mean MDS UPDRS3 score (25.1, SD 13.2) was significantly higher than in probable PD (22.3, SD 12.7, p = 0.016) but not established PD (22.9, SD 12.0, p = 0.066). The l-dopa equivalent daily dose of 341 mg (SD 261) in non-PD cases was significantly higher than in probable PD (250 mg, SD 214, p < 0.001) and established PD (308 mg, SD 199, p = 0.025). After 30 months' follow-up, 89.5% of clinically established cases at baseline remained as PD (established/probable), and 86.9% of those categorized as clinically probable at baseline remained as PD (established/probable). Cases not fulfilling PD criteria had more severe parkinsonism, in particular relating to postural instability, gait problems, and cognitive impairment. Conclusion: Over 90% of cases clinically diagnosed as early PD fulfilled the MDS criteria for PD. Those not fulfilling criteria may have an atypical parkinsonian disorder or secondary parkinsonism that is not correctly identified by the UK Brain Bank criteria, but possibly by the new criteria

Comparison between four published definitions of hyposmia in Parkinson's disease

Objectives Hyposmia is a common feature of Parkinson's disease (PD), yet there is no standard method to define it. A comparison of four published methods was performed to explore and highlight differences. Materials and methods Olfactory testing was performed in 2097 cases of early PD in two prospective studies. Olfaction was assessed using various cut-offs, usually corrected by age and/or gender. Control data were simulated based on the age and gender structure of the PD cases and published normal ranges. Association with age, gender, and disease duration was explored by method and study cohort. Prevalence of hyposmia was compared with the age and gender-matched simulated controls. Between method agreement was measured using Cohen's kappa and Gwet's AC1. Results Hyposmia was present in between 69.1% and 97.9% of cases in Tracking Parkinson's cases, and between 62.2% and 90.8% of cases in the Parkinson's Progression Marker Initiative, depending on the method. Between-method agreement varied (kappa 0.09–0.80, AC1 0.55–0.86). The absolute difference between PD cases and simulated controls was similar for men and women across methods. Age and male gender were positively associated with hyposmia (p < .001, all methods). Odds of having hyposmia increased with advancing age (OR:1.06, 95% CI:1.03, 1.10, p < .001). Longer disease duration had a negative impact on overall olfactory performance. Conclusions Different definitions of hyposmia give different results using the same dataset. A standardized definition of hyposmia in PD is required, adjusting for age and gender, to account for the background decline in olfactory performance with ageing, especially in men

Factor structure of the Montreal Cognitive Assessment in Parkinson’s disease

Objectives: The Montreal Cognitive Assessment (MoCA) is a common tool for screening mild cognitive impairment (MCI) and dementia. Studies in multiple clinical groups provide evidence for various factor structures mapping to different cognitive domains. We tested the factor structure of the MoCA in a large cohort of early Parkinson disease (PD). Materials and Methods: Complete MoCA data were available from an observational cohort study for 1738 patients with recent‐onset PD (64.6% male, mean age 67.6, SD 9.2). Confirmatory factor analysis (CFA) was applied to test previously defined two‐factor, six‐factor, and three‐factor models in the full sample and in a subgroup with possible cognitive impairment (MoCA < 26). Secondary analysis used exploratory factor analysis (EFA; principal factors with oblique rotation). Results: The mean MoCA score was 25.3 (SD 3.4, range 10‐30). Fit statistics in the six‐factor model (χ2/df 17.77, root mean square error of approximation [RMSEA] 0.10, comparative fit index [CFI] 0.74, Tucker‐Lewis index [TLI] 0.69, standardised root mean square residual [SRMR] 0.07) indicated poorer fit than did previous studies. Findings were similar in the two‐factor and three‐factor models. EFA suggested an alternative six‐factor solution (short‐term recall, visuospatial‐executive, attention/working memory, verbal‐executive, orientation, and expressive language), although CFA did not support the validity of the new model. Conclusions: The factor structure of the MoCA in early PD was not consistent with that of previous research. This may reflect higher cognitive performance and differing demographics in our sample. The results do not support a clear, clinically relevant factor structure in an early PD group, suggesting that the MoCA should be followed with detailed assessment to obtain domain‐specific cognitive profiles

Two sample Mendelian Randomisation using an outcome from a multilevel model of disease progression

Identifying factors that are causes of disease progression, especially in neurodegenerative diseases, is of considerable interest. Disease progression can be described as a trajectory of outcome over time—for example, a linear trajectory having both an intercept (severity at time zero) and a slope (rate of change). A technique for identifying causal relationships between one exposure and one outcome in observational data whilst avoiding bias due to confounding is two sample Mendelian Randomisation (2SMR). We consider a multivariate approach to 2SMR using a multilevel model for disease progression to estimate the causal effect an exposure has on the intercept and slope. We carry out a simulation study comparing a naïve univariate 2SMR approach to a multivariate 2SMR approach with one exposure that effects both the intercept and slope of an outcome that changes linearly with time since diagnosis. The simulation study results, across six different scenarios, for both approaches were similar with no evidence against a non-zero bias and appropriate coverage of the 95% confidence intervals (for intercept 93.4–96.2% and the slope 94.5–96.0%). The multivariate approach gives a better joint coverage of both the intercept and slope effects. We also apply our method to two Parkinson’s cohorts to examine the effect body mass index has on disease progression. There was no strong evidence that BMI affects disease progression, however the confidence intervals for both intercept and slope were wide

Vascular disease and vascular risk factors in relation to motor features and cognition in early Parkinson's disease

Funded by Parkinson's UK National Institute for Health Research (NIHR) DeNDRoN network NIHR Newcastle Biomedical Research Unit Newcastle University NIHR funded Biomedical Research Centre in CambridgePeer reviewedPublisher PD

A randomized trial of specialized versus standard neck physiotherapy in cervical dystonia

We thank: the patients who took part; Monsieur John-Pierre Bleton for training the physiotherapists; Gladys McPherson (Senior IT Manager), Adesoji Adeyemi (programmer) and Diana Collins (data entry) from the Centre for Healthcare Randomised Trials, University of Aberdeen who provided the randomisation and database service; and the funders including The Dystonia Society, the RS Macdonald Charitable Trust, The Sir Halley Stewart Trust, The Foyle Foundation and The Garfield Weston Foundation. The Dystonia Society and other funders had no role in the design, conduct, analysis or writing of the report or the decision to submit the manuscript.Peer reviewedPostprintPostprintPostprintPostprintPostprintPostprintPostprin

Tolerability of the Low-Affinity, Use-Dependent NMDA Antagonist AR-R15896AR in Stroke Patients

Background and Purpose—AR-R15896AR is a use-dependent, low-affinity blocker of the NMDA ion channel with neuroprotective effects in animal models of focal cerebral ischemia. This study aimed to establish the highest safe and tolerated loading and maintenance dosing regimen of AR-R15896AR in acute ischemic stroke patients and to determine the associated plasma concentrations of AR-R15896AR.Methods—This was a 4-part, multicenter, randomized, double-blind, placebo-controlled study in 175 patients (mean age, 69 years) within 24 hours of acute stroke symptom recognition. Ascending 60-minute intravenous infusion loading doses of AR-R15896AR were initially examined (100, 150, 200, 250, or 300 mg or placebo in 3:1 randomization, n=36 treated); in part 2, 250, 275, or 300 mg was compared with placebo (n=33). In part 3, a 250-mg loading dose was followed by 9 maintenance doses of 60, 75, 90, 105, or 120 mg every 8 hours versus placebo in 3:1 randomization (n=59); subsequently, in part 4, maintenance doses of 90, 105, and 120 mg after the 250-mg loading dose were directly randomized against placebo (n=42). Safety, tolerability, and pharmacokinetics were the primary end points; NIHSS at 1 week and Barthel and modified Rankin scores at 1 month were also recorded, but the study was neither designed nor powered to assess efficacy.Results—Rates for mortality and serious adverse events (SAE) were similar in active and placebo groups (9% mortality and 23% SAE for all active combined versus 11% mortality and 33% SAE for placebo). Adverse events associated with AR-R15896AR were dizziness, vomiting, nausea, stupor, and some agitation/hallucination. Withdrawal from treatment occurred only in response to loading doses with AR-R15896AR: placebo, 3 of 46 (7%); 250 mg, 11 of 89 (12%); 275 mg, 1 of 8 (12.5%); and 300 mg, 3 of 15 (20%). No significant difference in outcome was observed between groups. Plasma concentrations of AR-R15896AR were 1524±536 ng/mL at the end of the 250-mg loading infusion and were 1847±478 ng/mL at steady state after the 9 maintenance doses of 120 mg.Conclusions—The maximum tolerated loading infusion of AR-R15896AR in this study was 250 mg over a period of 1 hour. Subsequent maintenance infusions of 120 mg every 8 hours were well tolerated. With these doses, putative neuroprotective concentrations of 1240 ng/mL are attained by the loading dose and are satisfactorily maintained thereafter. The loading dose may be improved further by adjustment on an individual patient basis, but tolerability issues remain