Relationship between plasma NFL and disease progression in Parkinson's disease: a prospective cohort study

OBJECTIVE

We aimed to examine the longitudinal change of plasma neurofilament light chain (NFL) level and explore its diagnostic and prognostic implications in Parkinson's disease (PD).

METHODS

A total of 184 patients with early PD who completed 5-year annually repeated clinical assessments were included. Plasma NFL at baseline, 1 year, and 2 year were examined, which were quantified using the ultrasensitive Simoa technology. At baseline, blood from 86 sex- and age-matched healthy controls (HC) were obtained for comparison.

RESULTS

Plasma NFL in PD patients at baseline was significantly higher than those in HC (P = 0.046), and significantly increased after 2 years (P = 0.046). Receiver operating characteristic curve indicated that a plasma NFL cut-off value of 10.79 pg/mL resulted in 39.7% sensitivity and 84.0% specificity, with an area under the curve of 0.635, to distinguish PD from HC (P < 0.001). Linear mixed-effect models indicated that baseline plasma NFL (> 9.24 pg/mL) correlated with a greater increase in the Unified Parkinson's Disease Rating Scale III (estimate = 0.651, P = 0.001) and Hoehn & Yahr stage (estimate = 0.072, P < 0.001), and also correlated with a greater decrease in the Montreal Cognitive Assessment (estimate = - 0.387, P < 0.001) during follow-up visits.

CONCLUSIONS

Plasma NFL exhibits a tendency to increase with disease progression, and elevated baseline plasma NFL can serve as a predictor for accelerated motor deterioration and cognitive decline in PD. However, plasma NFL does not have high accuracy to distinguish individuals with early-stage PD from HC.

Parkinson's disease motor progression in relation to the timing of REM sleep behavior disorder presentation: an exploratory retrospective study

REM sleep behavior disorder (RBD) is a frequent non-motor symptom of Parkinson's disease (PD), and the timing of its presentation might have a role in the underlying neurodegenerative process. Here, we aimed to define the potential impact of probable RBD (pRBD) on PD motor progression.We conducted a longitudinal retrospective study on 66 PD patients followed up at the University Hospital of Rome Tor Vergata. Patients were divided into three groups: with post-motor pRBD (pRBDpost, n = 25), without pRBD (pRBDwo, n = 20), and with pre-motor pRBD (pRBDpre, n = 21). Hoehn and Yahr (H&Y) scores, Unified PD Rating Scale (UPDRS) motor scores, and levodopa equivalent daily dose were collected at two follow-up visits conducted in a 5-year interval (T0 and T1). pRBDpost patients had a greater rate of motor progression in terms of the H&Y scale compared to pRBDpre and pRBDwo patients, without the influence of anti-parkinsonian treatment.These preliminary findings suggest that the post-motor occurrence of pRBD can be associated with an acceleration in PD motor progression.

Evaluating motor progression of juvenile-onset Huntington's Disease: An Enroll-HD analysis

INTRODUCTION

Juvenile-onset Huntington's disease (JOHD) is characterized by a unique motor phenotype relative to patients with adult-onset Huntington's Disease (AOHD). This study characterized motor progression of JOHD to propose improved outcome measures for this group.

METHODS

We used linear mixed effect regression models to compare progression of the Unified Huntington's Disease Rating Scale (UHDRS) Total Motor Score (TMS) and the chorea score between patients with JOHD and AOHD. We then evaluated all 31 subscales that make up the UHDRS over time within patients with JOHD to identify measures that may be used to track motor progression most reliably.

RESULTS

The JOHD cohort had faster TMS progression compared to AOHD (p = 0.006) but no group difference in the rate of change of chorea. Patients with JOHD did not show significant change in any of the chorea subscales. The subscales that changed most reliably over time amongst patients with JOHD were dysarthria, upper extremity dystonia, tandem walking, gait, bilateral pronate/supinate, bilateral finger-tapping, and tongue protrusion. When these subscales were summed, they progressed at a faster rate (7.07%, 95% CI [5.96-8.18]) than the TMS (4.92%, 95% CI [3.95-5.89]).

CONCLUSION

While the TMS changes at a significant rate in JOHD subjects, not all subscales that make up the TMS accurately represent the unique motor features of JOHD. A JOHD-specific scale performed better at tracking motor progression relative to the TMS. This scale may improve clinical care for patients with JOHD and allow for the development of more efficient clinical trials.

Proximity to residential and workplace pesticides application and the risk of progression of Parkinson's diseases in Central California

BACKGROUND

Pesticide exposure has consistently been associated with Parkinson's disease (PD) onset. Yet, fewer epidemiologic studies have examined whether pesticides influence PD motor and non-motor symptom progression.

OBJECTIVES

Using a geographic information system tool that integrates agricultural pesticide use reports and land use records to derive ambient exposures at residences and workplaces, we assessed associations between specific pesticides previously related to PD onset with PD symptom progression in two PD patient cohorts living in agricultural regions of California.

METHODS

We calculated the pounds of pesticide applied agriculturally near each participant's residential or occupational addresses from 1974 to the year of PD diagnosis, using a geographic information system tool that links the California Pesticide Use Reports database to land use data. We examined 53 pesticides selected a priori as they have previously been associated with PD onset. We longitudinally followed two PD patient cohorts (PEG1 N = 242, PEG2 N = 259) for an average of 5.0 years (SD ± 3.5) and 2.7 years (SD ± 1.6) respectively and assessed PD symptoms using the movement disorder specialist-administered Unified Parkinson's disease Rating Scale part III (UPDRS), Mini-Mental State Examination (MMSE), and Geriatric Depression Scale (GDS). Weighted time-to-event regression models were implemented to estimate effects.

RESULTS

Ten agricultural pesticides, including copper sulfate (pentahydrate), 2-methyl-4-chlorophenoxyacetic acid (MCPA) dimethylamine salt, tribufos, sodium cacodylate, methamidophos, ethephon, propargite, bromoxynil octanoate, monosodium methanearsonate (MSMA), and dicamba, were associated with faster symptom progression. Among these pesticides, residential or workplace proximity to higher amounts of copper sulfate (pentahydrate) and MCPA (dimethylamine salt) was associated with all three progression endpoints (copper sulfate: HRs = 1.22-1.36, 95 % CIs = 1.03-1.73; MCPA: HRs = 1.27-1.35, 95 % CIs = 1.02-1.70).

CONCLUSIONS

Our findings suggest that pesticide exposure may not only be relevant for PD onset but also PD progression phenotypes. We have implicated ten specific pesticide active ingredients in faster PD motor and non-motor decline.

Polysomnographic Predictors of Sleep, Motor, and Cognitive Dysfunction Progression in Parkinson's Disease

PURPOSE OF REVIEW

Sleep disturbances are an important nonmotor feature of Parkinson's disease (PD) that can cause polysomnographic (PSG) alterations. These alterations are already present in early PD and may be associated with a specific disease course. This systematic review describes the role of PSG variables as predictors of sleep dysfunction, motor and cognitive dysfunction progression in PD.

RECENT FINDINGS

Nineteen longitudinal cohort studies were included. Their main findings were that (1) REM sleep behavioral events, REM sleep without atonia (RSWA), and electroencephalography (EEG) changes (mainly microsleep instability) are predictors of the development of REM sleep behavior disorder (RBD); (2) RBD, RSWA, and lower slow-wave sleep energy predict motor progression; (3) RBD, EEG slowing, and sleep spindles changes are predictors of cognitive deterioration; and (4) OSA is associated with severe motor and cognitive symptoms at baseline, with inconsistent findings on the effect of continuous positive airway pressure (CPAP) therapy for these symptoms. The results of our systematic review support a role of the video-PSG in disease progression prediction in PD and its usefulness as a biomarker. However, future studies are needed to investigate whether treatment of these PSG abnormalities and sleep disturbances may have a neuroprotective effect on disease progression.

A comparison of characteristics, developmental disorders and motor progression between children with and without developmental coordination disorder

BACKGROUND AND AIM

Children with Developmental Coordination Disorder (DCD) have difficulty in the development of motor coordination and with learning new motor skills. Studies demonstrate that children with DCD differ in terms of the nature and severity of their motor difficulties, the incidence of co occurring conditions and family background. However, little is known whether these profiles may relate to motor progression over time. The aim of this study was to describe the profiles of children with and without DCD and track motor progression over time.

METHOD

The characteristics of thirty-four 7-14 year old children (M = 10.07, 85.3% boys) with and without DCD were compared and their motor progression monitored over a two academic years. DCD was identified using DSM5 criteria. The Movement Assessment Battery for Children-2 (MABC-2) was used to classify children as TD (≥25th percentile), having moderate motor coordination difficulties (6-16th percentile) or severe motor coordination difficulties (≤ 5th percentile). The Kaufman Brief Intelligence Test - 2 (KBIT-2) was used to measure full scale IQ. Parent questionnaires were used to gather information on socio economic status and co occurrence of other developmental disorders. We used ANOVA to assess whether there were differences in characteristics between the TD children, children with severe motor coordination difficulties and children with moderate motor coordination difficulties. Linear mixed effect modelling was used to estimate any change in motor performance over time and whether this differed between the three groups of children.

RESULTS

Children with severe motor coordination difficulties had distinct profiles in motor and non-motor domains, lower IQ and a greater likelihood of having associated characteristics of 2 or more developmental disorders. We found significant differences between the poor motor performance of the severe group compared to the other two groups. Longitudinal analyses revealed stable, persistent and lower motor competence for the severe group. The rate of change in motor proficiency for the typical and severe groups was similar. However, the group with moderate motor difficulties gained on average more points per week compared to the typical group and achieved motor scores in the typically developing range over time.

CONCLUSIONS

This is one of the first studies to compare the characteristics and rate of motor progression of children with and without DCD using different motor proficiency cut off scores. The children with severe motor coordination difficulties progressed at the same rate as typically developing peers but remained in the severe group over time, whereas the children with moderate motor coordination difficulties caught up to TDC. The results indicate that different intervention may be required according to the nature and severity of the characteristics in both the motor and non-motor domains of children with DCD.

New markers in Parkinson's disease

Parkinson's disease (PD) is a chronic, debilitating neurodegenerative disorder characterized clinically by a variety of progressive motor and nonmotor symptoms. Currently, there is a dearth of diagnostic tools available to predict, diagnose or mitigate disease risk or progression, leading to a challenging dilemma within the healthcare management system. The search for a reliable biomarker for PD that reflects underlying pathology is a high priority in PD research. Currently, there is no reliable single biomarker predictive of risk for motor and cognitive decline, and there have been few longitudinal studies of temporal progression. A combination of multiple biomarkers might facilitate earlier diagnosis and more accurate prognosis in PD. In this review, we focus on the recent developments of serial biomarkers for PD from a variety of clinical, biochemical, genetic and neuroimaging perspectives.

Clinical progression in Parkinson's disease with features of REM sleep behavior disorder: A population-based longitudinal study

INTRODUCTION

Rapid Eye Movement (REM) sleep behavior disorder (RBD) is characterized by dream enactment and is associated with incidence of neurodegenerative disorders, especially Parkinson's disease (PD). Whether PD with RBD constitutes a distinct subtype with unique progression is unknown. Here, we investigated motor and cognitive symptom progression in patients with self-reported RBD features in adult life.

METHODS

We screened for RBD in a cohort of 776 PD patients whom we ascertained using a population-based strategy. Among participants with at least one follow-up (60%), we compared those with and without probable RBD (pRBD) estimating hazard rate ratios for progression events UPDRS-III≥ 35 and MMSE≤ 24.

RESULTS

Prevalence of pRBD at baseline was 21%. In adjusted Cox regression models among patients with a Postural Instability and Gait Dysfunction (PIGD) phenotype, those with pRBD progressed faster to a UPDRS-III≥ 35 (HR = 1.92, 95% CI = 1.12; 3.27). Also, all patients with pRBD progressed twice as fast to a MMSE score≤ 24 (HR = 2.04, 95% CI = 1.13; 3.69). In sensitivity analyses, using alternative definition of pRBD and accounting for bias due to loss to follow-up results remained similar.

DISCUSSION

Employing data from one of the largest population-based studies of PD, in which movement disorder specialists assessed patients, we confirm evidence that pRBD features are a clinical marker for faster cognitive decline and possibly also motor progression in PD patients, the latter for patients with a PIGD subtype early in disease.

Variants in GBA, SNCA, and MAPT influence Parkinson disease risk, age at onset, and progression

Multiple genetic variants have been linked to risk of Parkinson disease (PD), but known mutations do not explain a large proportion of the total PD cases. Similarly, multiple loci have been associated with PD risk by genome-wide association studies (GWAS). The influence that genetic factors confer on phenotypic diversity remains unclear. Few studies have been performed to determine whether the GWAS loci are also associated with age at onset (AAO) or motor progression. We used 2 PD case-control data sets (Washington University and the Parkinson's Progression Markers Initiative) to determine whether polymorphisms located at the GWAS top hits (GBA, ACMSD/TMEM163, STK39, MCCC1/LAMP3, GAK/TMEM175, SNCA, and MAPT) show association with AAO or motor progression. We found associations between single nucleotide polymorphisms at the GBA and MAPT loci and PD AAO and progression. These findings reinforce the complex genetic basis of PD and suggest that distinct genes and variants explain the genetic architecture of PD risk, onset, and progression.