Validation of the Rainbow Model of Integrated Care Measurement Tool in Parkinson's Disease

Background

Integrated care is essential for improving the management and health outcomes for people with Parkinson's disease (PD); reliable and objective measures of care integration are few.

Objective

The aim of this study was to test the psychometric properties of the Rainbow Model of Integrated Care Measurement Tool (RMIC-MT, provider version) for healthcare professionals involved in PD care.

Methods

A cross-sectional survey was administered online to an international network representing 95 neurology centers across 41 countries and 588 healthcare providers. Exploratory factor analysis with principal axis extraction method was used to assess construct validity. Confirmatory factor analysis was used to evaluate model fit of the RMIC-MT provider version. Cronbach's alpha was used to assess the internal consistency reliability.

Results

Overall, 371 care providers (62% response rate) participated in this study. No item had psychometric sensitivity problems. Nine factors (professional coordination, cultural competence, triple aims outcome, system coordination, clinical coordination, technical competence, community-centeredness, person-centeredness, and organizational coordination) with 42 items were determined by exploratory factor analysis. Cronbach's alpha ranged from 0.76 (clinical coordination) to 0.94 (system coordination) and showed significant correlation among all items in the scale (>0.4), indicating good internal consistency reliability. The confirmatory factor analysis model passed most goodness-of-fit tests, thereby confirming the factor structure of nine categories with a total of 40 items.

Conclusions

The results provide evidence for the construct validity and other psychometric properties of the provider version of the RMIC-MT to measure integrated care in PD. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.     

Evaluation of Parkinson's disease in entrants on the Nebraska State Parkinson's Disease Registry.

We examined a sample of individuals in the Nebraska State Parkinson's Disease Registry (NSPDR) to determine what proportion meets standard criteria for Parkinson's disease (PD). The NSPDR was established in 1996 in an effort to understand the high prevalence of PD in Nebraska. Only minimal demographic data are included for each entrant. Subjects enter the NSPDR by means of diagnosing physicians, pharmacists dispensing anti-PD medications and the patients themselves. A series of 356 registrants diagnosed between 1997 and 2001 were contacted and invited to participate in a case-control study. Medical records were reviewed by a single abstractor in a standard manner. When patients consented, history was filled in by interview. A subset of patients were examined by a movement disorders specialist, who assigned all patients a probability of PD. Where sufficient information was available, 78% of registrants were confirmed to have PD (i.e., percent probability > 50%), including 83% of the patients previously diagnosed by a neurologist. Tremor was an initial symptom in 72% of confirmed versus 39% of excluded cases, and resting tremor was present in 86% of those that were confirmed. The most frequent reasons for exclusion were drug-induced Parkinsonism, multiple systems atrophy, vascular disease, and essential tremor. Use of the NSPDR for epidemiologic study requires careful review of the data set before assignment of cases. When histories are compiled in a standardized, comprehensive manner, the necessity for actual patient examinations can be minimized.     

Task-Related Reorganization of Cognitive Network in Parkinson's Disease Using Electrophysiology

Background

Cognitive deficits in Parkinson's disease (PD) patients are well described, however, their underlying neural mechanisms as assessed by electrophysiology are not clear.

Objectives

To reveal specific neural network alterations during the performance of cognitive tasks in PD patients using electroencephalography (EEG).

Methods

Ninety participants, 60 PD patients and 30 controls underwent EEG recording while performing a GO/NOGO task. Source localization of 16 regions of interest known to play a pivotal role in GO/NOGO task was performed to assess power density and connectivity within this cognitive network. The connectivity matrices were evaluated using a graph-theory approach that included measures of cluster-coefficient, degree, and global-efficiency. A mixed-model analysis, corrected for age and levodopa equivalent daily dose was performed to examine neural changes between PD patients and controls.

Results

PD patients performed worse in the GO/NOGO task (P < 0.001). The power density was higher in δ and θ bands, but lower in α and β bands in PD patients compared to controls (interaction group × band: P < 0.001), indicating a general slowness within the network. Patients had more connections within the network (P < 0.034) than controls and these were used for graph-theory analysis. Differences between groups in graph-theory measures were found only in cluster-coefficient, which was higher in PD compared to controls (interaction group × band: P < 0.001).

Conclusions

Cognitive deficits in PD are underlined by alterations at the brain network level, including higher δ and θ activity, lower α and β activity, increased connectivity, and segregated network organization. These findings may have important implications on future adaptive deep brain stimulation. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.     

Scoliosis in Patients with Parkinson's Disease

Background and purpose

Scoliosis is more common in patients with Parkinson''s disease (PD) than in the general elderly population. We compared clinical characteristics between PD patients with and without scoliosis, to identify the relationship between the direction of scoliosis and the laterality of the dominant symptoms of PD. We also studied the associations between dopaminergic pharmacotherapy and scoliosis (defined by a spinal curvature deviation of 10° or larger).

Methods

The study population comprised 97 patients (42 men and 55 women) with idiopathic PD. All of the patients submitted to a whole-spine scanograph to allow measurement of the degree of scoliosis by Cobb''s method.

Results

True scoliosis was found in 32 of the 97 PD patients, and was observed more frequently in women than in men (28 vs. 4, respectively; p=0.006). The age of patients without scoliosis was significantly lower than that of those with scoliosis (66.5±9.2 years vs. 72.8±7.3 years, respectively, mean±SD, p<0.001). There was no correlation between PD symptom laterality and scoliosis. The rate of occurrence of scoliosis did not differ between de novo and levodopa (L-dopa)-treated patients.

Conclusions

We suggest that neither L-dopa treatment nor the laterality of the initial symptoms of PD is related to the appearance of scoliosis.     

Cognitive Impairment in Parkinson's Disease without Dementia: Subtypes and Influences of Age

Background and Purpose

Cognitive impairments are common in Parkinson''s disease (PD), although the severity of these impairments does not significantly impair the patient''s daily activities. The aim of this study was to determine the frequency of mild cognitive impairment (MCI) of Parkinson''s disease (PDMCI) and its subtypes in nondemented PD patients. We also evaluated the influence of age on the pattern of subtypes of PDMCI.

Methods

A total of 141 consecutive, nondemented PD patients underwent a comprehensive neuropsychological assessment covering the five cognitive domains: attention, language, visuospatial, memory, and executive functions. PDMCI was defined as impaired performance in at least one of these five cognitive domains. The influence of age on the distribution of subtypes of PDMCI was assessed by comparing patients in two groups dichotomized according to their age at assessment (younger vs. older).

Results

Fifty-seven (40.4%) of the nondemented PD patients had an impairment in at least one domain, and were therefore considered as having PDMCI. The age at assessment and age at disease onset were significantly higher in the PDMCI patients. The amnestic type of PDMCI was the most frequent, followed by the visuospatial, linguistic, executive, and attention types in that order. The frequency of PDMCI was higher for all subtypes in the older group; the domain that was influenced the most by age was executive function.

Conclusions

MCI was common in PD and the subtypes were diverse. Age was found to be an important risk factor for the development of PDMCI, particularly for the executive subtype. These results indicate that the concept of MCI should be introduced in PD.     

Integrated Multi-Cohort Analysis of the Parkinson's Disease Gut Metagenome

Background

The gut microbiome is altered in several neurologic disorders, including Parkinson's disease (PD).

Objectives

The aim is to profile the fecal gut metagenome in PD for alterations in microbial composition, taxon abundance, metabolic pathways, and microbial gene products, and their relationship with disease progression.

Methods

Shotgun metagenomic sequencing was conducted on 244 stool donors from two independent cohorts in the United States, including individuals with PD (n = 48, n = 47, respectively), environmental household controls (HC, n = 29, n = 30), and community population controls (PC, n = 41, n = 49). Microbial features consistently altered in PD compared to HC and PC subjects were identified. Data were cross-referenced to public metagenomic data sets from two previous studies in Germany and China to determine generalizable microbiome features.

Results

We find several significantly altered taxa between PD and controls within the two cohorts sequenced in this study. Analysis across global cohorts returns consistent changes only in Intestinimonas butyriciproducens. Pathway enrichment analysis reveals disruptions in microbial carbohydrate and lipid metabolism and increased amino acid and nucleotide metabolism in PD. Global gene-level signatures indicate an increased response to oxidative stress, decreased cellular growth and microbial motility, and disrupted intercommunity signaling.

Conclusions

A metagenomic meta-analysis of PD shows consistent and novel alterations in functional metabolic potential and microbial gene abundance across four independent studies from three continents. These data reveal that stereotypic changes in the functional potential of the gut microbiome are a consistent feature of PD, highlighting potential diagnostic and therapeutic avenues for future research. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.     

A Pilot Study to Investigate the Feasibility of Electrical Stimulation to Assist Gait in Parkinson's Disease

Objectives. This study aims to investigate the effect of functional electrical stimulation (FES) on gait in people with Parkinson's disease. Materials and Methods. Seven subjects with idiopathic Parkinson's disease received single‐channel electrical stimulation for eight weeks to the common peroneal nerve to improve heel strike and provide sensory stimulus during the swing phase of gait. Stride length, time, and number of steps to complete a 20‐m walk and distance completed in 3 min were assessed. Episodes of freezing and incidence of falls were recorded. Statistical analysis of the walking test data was analyzed using the nonparametric Wilcoxon signed ranks test. Results. An immediate improvement was demonstrated with FES on distance and average stride length during a 3‐min walk during the treatment period but not on number of steps and walking speed during a 20‐m walk. A training effect was observed for all parameters of gait measured over the eight‐week treatment period, which was mostly maintained four weeks after treatment was stopped. Fewer falls and episodes of freezing occurred during the treatment period. The number of falls returned to pretreatment levels when treatment was stopped. Conclusions. This study has shown that FES can improve some parameters of gait over an eight‐week period of use with a carryover effect that is maintained without stimulation during that time and an immediate reduction in the frequency of falls. An immediate effect of FES was demonstrated over a 3‐min walk but not over a 20‐m walk. Improvements in gait largely persisted on reassessment four weeks after stopping use of FES although the frequency of falls returned to pretreatment levels. A larger study is required to support these findings, to understand the mechanisms of the effects of electrical stimulation on gait and to identify those most likely to benefit from it.