The latest medical research on Parkinson’s Disease

The research magnet gathers the latest research from around the web, based on your specialty area. Below you will find a sample of some of the most recent articles from reputable medical journals about parkinson’s disease gathered by our medical AI research bot.

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Advice to People with Parkinson's in My Clinic: Cannabis.

Journal Parkinsons Disease

Cannabis (in all the varied methods of delivery) continues to garner significant attention as a potential therapeutic intervention for neurodegener...

Parkinson's Disease Associated with G2019S LRRK2 Mutations without Lewy Body Pathology.

"Movement Disorders Clinical Practice

The G2019S leucine-rich repeat kinase 2 (LRRK2) gene mutation is an important and commonly found genetic determinant of Parkinson's disease (PD). The neuropathological findings associated with this mutation have thus far been varied but are most often associated with Lewy body (LB) pathology.

Describe a case of clinical Parkinson's disease with levodopa responsiveness found to have LRRK2 mutations and the absence of Lewy bodies.

We present an 89-year-old man with a 10-year history of slowly progressive parkinsonism suspected to be secondary to Parkinson's disease.

Neuropathological evaluation revealed nigral degeneration without Lewy bodies or Lewy neurites, but there were frequent tau-immunopositive neurites and astrocytes in the putamen and substantia nigra, neocortical glial tau positive astrocytes associated with aging-related tau astrogliopathy (ARTAG), as well as neurofibrillary tangles, beta amyloid plaques, and amyloid angiopathy typical of advanced Alzheimer's disease. G2019S LRRK2 homozygous mutations were found.

This case illustrates that levodopa-responsive clinical PD caused by G2019S LRRK2 mutations can occur without Lewy bodies.

Movement Disorders in Patients with Subacute Sclerosing Panencephalitis: A Systematic Review.

"Movement Disorders Clinical Practice

Subacute sclerosing panencephalitis (SSPE) is a complication of measles, occurring after a latency of 4-10 years. It continues to occur in developing countries although resurgence is being reported from developed countries. Characteristic features include progressive neuropsychiatric issues, myoclonus, seizures, movement disorders and visual impairment. Electroencephalography (EEG) typically shows periodic generalized discharges, and elevated CSF anti-measles antibodies are diagnostic. Movement disorders are being increasingly recognized as part of the clinical spectrum, and range from hyperkinetic (chorea, dystonia, tremor, tics) to hypokinetic (parkinsonism) disorders and ataxia.

This article aims to comprehensively review the spectrum of movement disorders associated with SSPE.

A literature search was conducted in PubMed and EMBASE databases in December 2023 and articles were identified for review.

Movement disorders reported in SSPE included hyperkinetic (chorea, dystonia, tremor and tics), hypokinetic (parkinsonism), ataxia and extraocular movement disorders. Myoclonus, a core clinical feature, was the most frequent "abnormal movement." Movement disorders were observed in all clinical stages, and could also be a presenting feature, even sans myoclonus. Hyperkinetic movement disorders were more common than hypokinetic movement disorders. An evolution of movement disorders was observed, with ataxia, chorea and dystonia occurring earlier, and parkinsonism later in the disease. Neuroradiological correlates of movement disorders remained unclear.

A wide spectrum of movement disorders was observed throughout the clinical stages of SSPE. Most data were derived from case reports and small case series. Multicentric longitudinal studies are required to better delineate the spectrum and evolution of movement disorders in SSPE.

Understanding Anxiety in Cervical Dystonia: An Imaging Study.

"Movement Disorders Clinical Practice

Anxiety may precede motor symptoms in cervical dystonia (CD) and is associated with an earlier onset of dystonia. Our understanding of anxiety in CD is inadequate.

To investigate brain networks associated with anxiety in CD.

Twenty-six subjects with idiopathic CD underwent MRI Brain without contrast. Correlational tractography was derived using Diffusion MRI connectometry. Quantitative Anisotropy (QA) was used in deterministic diffusion fiber tracking. Correlational tractography was then used to correlate QA with State-Trait Anxiety Inventory (STAI) state (STAI-S) and trait (STAI-T) subscales.

Connectometry analysis showed direct correlation between state anxiety and QA in tracts from amygdala to thalamus/ pulvinar bilaterally, and trait anxiety and QA in tracts from amygdala to motor cortex, sensorimotor cortex and parietal association area bilaterally (FDR ≤0.05).

Our efforts to map anxiety to brain networks in CD highlight the role of the amygdala in the pathophysiology of anxiety in CD.

Levodopa-Induced Dyskinesias are Frequent and Impact Quality of Life in Parkinson's Disease: A 5-Year Follow-Up Study.

"Movement Disorders Clinical Practice

Levodopa-induced dyskinesias (LID) are frequent in Parkinson's disease (PD).

To analyze the change in the frequency of LID over time, identify LID related factors, and characterize how LID impact on patients' quality of life (QoL).

PD patients from the 5-year follow-up COPPADIS cohort were included. LID were defined as a non-zero score in the item "Time spent with dyskinesia" of the Unified Parkinson's Disease Rating Scale-part IV (UPDRS-IV). The UPDRS-IV was applied at baseline (V0) and annually for 5 years. The 39-item Parkinson's disease Questionnaire Summary Index (PQ-39SI) was used to asses QoL.

The frequency of LID at V0 in 672 PD patients (62.4 ± 8.9 years old; 60.1% males) with a mean disease duration of 5.5 ± 4.3 years was 18.9% (127/672) and increased progressively to 42.6% (185/434) at 5-year follow-up (V5). The frequency of disabling LID, painful LID, and morning dystonia increased from 6.9%, 3.3%, and 10.6% at V0 to 17.3%, 5.5%, and 24% at V5, respectively. Significant independent factors associated with LID (P < 0.05) were a longer disease duration and time under levodopa treatment, a higher dose of levodopa, a lower weight and dose of dopamine agonist, pain severity and the presence of motor fluctuations. LID at V0 (β = 0.073; P = 0.027; R2 = 0.62) and to develop disabling LID at V5 (β = 0.088; P = 0.009; R2 = 0.73) were independently associated with a higher score on the PDQ-39SI.

LID are frequent in PD patients. A higher dose of levodopa and lower weight were factors associated to LID. LID significantly impact QoL.

Skull Density Ratio as Arm-Allocation Parameter for a Controlled Focused Ultrasound Trial in Parkinson's Disease.

"Movement Disorders Clinical Practice

MR-guided focused ultrasound (FUS) thermoablation is an established therapy for movement disorders. FUS candidates must meet a predefined threshold of skull density ratio (SDR), a parameter that accounts for the efficiency in reaching ablative temperatures. Randomized sham-controlled trials to provide definitive therapeutic evidence employ pure randomization of subjects into active treatment or control arms. The latter design has several general limitations.

To demonstrate that SDR values are not associated with clinically and demographically relevant variables in patients with Parkinson's disease (PD). This in turn would allow using SDR as an arm-allocation parameter, separating patients who will receive active FUS treatment and best medical management treatment (BMT).

We studied a cohort of 215 PD patients who were candidates for FUS subthalamotomy to determine if the SDR was correlated with demographic or clinical variables that could introduce bias for group allocation in a controlled trial.

SDR was unassociated with age, gender, and clinical motor features nor with levodopa daily dose in our cohort of PD patients. A negative association with age was found for the female subgroup.

Our results show that in a PD population considered for FUS subthalamotomy treatment, the SDR may be a valid group-allocation parameter. This could be considered as the basis for a controlled study comparing FUS subthalamotomy vs BMT.

Assessing the Role of Locus Coeruleus Degeneration in Essential Tremor and Parkinson's Disease with Sleep Disorders.

Journal Parkinsons Disease

Previous studies have demonstrated the importance of the locus coeruleus (LC) in sleep-wake regulation. Both essential tremor (ET) and Parkinson's disease (PD) share common sleep disorders, such as poor quality of sleep (QoS). LC pathology is a feature of both diseases. A question arises regarding the contribution of LC degeneration to the occurrence of poor QoS.

To evaluate the association between LC impairment and sleep disorders in ET and PD patients.

A total of 83 patients with ET, 124 with PD, and 83 healthy individuals were recruited and divided into ET/PD with/without poor QoS (Sle/NorET and Sle/NorPD) subgroups according to individual Pittsburgh Sleep Quality Index (PSQI) score. Neuromelanin-sensitive magnetic resonance imaging (NM-MRI) and free-water imaging derived from diffusion MRI were performed. Subsequently, we evaluated the association between contrast-to-noise ratio of LC (CNRLC) and free-water value of LC (FWLC) with PSQI scores in ET and PD groups.

CNRLC was significantly lower in ET (p = 0.047) and PD (p = 0.018) than in healthy individuals, whereas no significant difference was found in FWLC among the groups. No significant differences were observed in CNR/FWLC between patients with/without sleep disorders after multiple comparison correction. No correlation was identified between CNR/FWLC and PSQI in ET and PD patients.

LC degeneration was observed in both ET and PD patients, implicating its involvement in the pathophysiology of both diseases. Additionally, no significant association was observed between LC integrity and PSQI, suggesting that LC impairment might not directly relate to overall QoS.

Effects of Continuous Dopaminergic Stimulation on Parkinson's Disease Gait: A Longitudinal Prospective Study with Levodopa Intestinal Gel Infusion.

Journal Parkinsons Disease

Gait issues, including reduced speed, stride length and freezing of gait (FoG), are disabling in advanced phases of Parkinson's disease (PD), and their treatment is challenging. Levodopa/carbidopa intestinal gel (LCIG) can improve these symptoms in PD patients with suboptimal control of motor fluctuations, but it is unclear if continuous dopaminergic stimulation can further improve gait issues, independently from reducing Off-time.

To analyze before (T0) and after 3 (T1) and 6 (T2) months of LCIG initiation: a) the objective improvement of gait and balance; b) the improvement of FoG severity; c) the improvement of motor complications and their correlation with changes in gait parameters and FoG severity.

This prospective, longitudinal 6-months study analyzed quantitative gait parameters using wearable inertial sensors, FoG with the New Freezing of Gait Questionnaire (NFoG-Q), and motor complications, as per the MDS-UPDRS part IV scores.

Gait speed and stride length increased and duration of Timed up and Go and of sit-to-stand transition was significantly reduced comparing T0 with T2, but not between T0-T1. NFoG-Q score decreased significantly from 19.3±4.6 (T0) to 11.8±7.9 (T1) and 8.4±7.6 (T2) (T1-T0 p = 0.018; T2-T0 p <  0.001). Improvement of MDS-UPDRS-IV (T0-T2, p = 0.002, T0-T1 p = 0.024) was not correlated with improvement of gait parameters and NFoG-Q from T0 to T2. LEDD did not change significantly after LCIG initiation.

Continuous dopaminergic stimulation provided by LCIG infusion progressively ameliorates gait and alleviates FoG in PD patients over time, independently from improvement of motor fluctuations and without increase of daily dosage of dopaminergic therapy.

Ciita Regulates Local and Systemic Immune Responses in a Combined rAAV-α-synuclein and Preformed Fibril-Induced Rat Model for Parkinson's Disease.

Journal Parkinsons Disease

Parkinson's disease (PD) is characterized by alpha-synuclein (α-Syn) pathology, neurodegeneration and neuroinflammation. Human leukocyte antigen (HLA) variants associated with PD and α-Syn specific CD4+ T lymphocytes in PD patients highlight the importance of antigen presentation in PD etiology. The class II transactivator (CIITA) regulates major histocompatibility complex class II (MHCII) expression. Reduced Ciita levels significantly increase α-Syn pathology, nigrostriatal neurodegeneration and behavioral deficits in α-Syn-induced rat PD models.

Characterize immune profiles associated with enhanced PD-like pathology observed in rats expressing lower Ciita levels (DA.VRA4) compared to the background strain (DA).

To model PD, we combined rAAV-mediated α-Syn overexpression in the substantia nigra with striatal injection of α-Syn preformed fibrils. Immune profiles in brain and blood were analyzed by flow cytometry and multiplexed ELISA in naïve rats, 4- and 8 weeks post rAAV injection.

Flow cytometry showed Ciita-dependent regulation of MHCII on microglia, brain macrophages and circulating myeloid cells. The MHCII-dependent microglial response was highest at 4 weeks post rAAV injection, whereas the MHCII levels in circulating myeloid cells was highest at 8 weeks. There was no major infiltration of macrophages or T lymphocytes into the CNS in response to α-Syn and only subtle Ciita- and/or α-Syn-dependent changes in the T lymphocyte compartment. Lower Ciita levels were consistently associated with higher TNF levels in serum.

Ciita regulates susceptibility to PD-like pathology through minor but detectable changes in resident and peripheral immune cells and TNF levels, indicating that mild immunomodulatory therapies could have therapeutic effects in PD.

Atypical Presentations of Huntington Disease-like 2 in South African Individuals.

"Movement Disorders Clinical Practice

Huntington disease-like 2 (HDL2) is a neurodegenerative disorder, affecting only individuals of African ancestry. Full penetrance occurs in individuals with 40 repeats or more.

To describe the phenotypic variability of HDL2 in a group of mixed ancestry individuals from South Africa.

Eight patients were assessed with analysis of repeat size and magnetic resonance brain imaging. We applied the Unified Huntington's Disease Rating Scale (UHDRS), but in deceased patients (4), this was estimated from video material.

Cognitive domains were more severely affected than motor; UHDRS motor scores were notable for bradykinesia, and to a slightly lesser extent, for rigidity and dystonia; a single patient had marked chorea. Repeat lengths ranged from 45 to 63 (median, 52).

This South African group of mixed ancestry HDL2 individuals presented with severe cognitive and behavioral impairments, with lesser degrees or absence of chorea. This presentation is possibly related to large repeat sizes.

Long-Term Medication Profiles in Parkinson's Disease under Subthalamic Deep Brain Stimulation: A Controlled Study.

"Movement Disorders Clinical Practice

Subthalamic deep brain stimulation (STN-DBS) reduces antiparkinsonian medications in Parkinson's disease (PD) compared with the preoperative state. Longitudinal and comparative studies on this effect are lacking.

To compare longitudinal trajectories of antiparkinsonian medication in STN-DBS treated patients to non-surgically treated control patients.

We collected retrospective information on antiparkinsonian medication from PD patients that underwent subthalamic DBS between 1999 and 2010 and control PD patients similar in age at onset and baseline, sex-distribution, and comorbidities.

In 74 DBS patients levodopa-equivalent daily dose (LEDD) were reduced by 33.9-56.0% in relation to the preoperative baseline over the 14-year observational period. In 61 control patients LEDDs increased over approximately 10 years, causing a significant divergence between groups. The largest difference amongst single drug-classes was observed for dopamine agonists.

In PD patients, chronic STN-DBS was associated with a lower LEDD compared with control patients over 14 years.

The Quality in Quality of Life in Parkinson's Disease: A Qualitative Meta-Synthesis.

"Movement Disorders Clinical Practice

Quality of life (QoL) is known to be impaired in people with Parkinson's disease (PwPD). Not surprisingly, a considerable effort of health interventions is aimed at maintaining or improving QoL. Yet, little is known about its determinants from a PwPD perspective to inform person-centered health care interventions.

This systematic review aims to overcome this information gap by synthesizing existing evidence on factors associated with PwPD' self-perceived QoL.

We searched six electronic databases (MEDLINE, EMBASE, PsycINFO, CINAHL, Web of Science, Cochrane Library) from inception to January 2022 for eligible qualitative studies of QoL in PwPD, supplemented by citation tracking and hand searching. Study quality was assessed using the QualSyst tool. In order to characterize the determinants of QoL in PwPD, we conducted a qualitative meta-synthesis.

Our analysis revealed a wide range of facilitators and barriers to QoL relating to seven overarching themes: Illness experience, health care, everyday life, social life, identity, spirituality/religion, and environment.

Our systematic review reinforces the impact of symptom experience on PwPD's QoL. However, it also highlights the need to consider the non-physical dimensions of PD when assessing patients' QoL. It is therefore essential that health care professionals acknowledge the psychological, social and spiritual repercussions of PD and endeavor to respond to these concerns through a comprehensive and patient-centered strategy. Further research is needed to gain a deeper understanding of these facets of PD and to formulate successful interventions aimed at improving the QoL of PwPD.