Musculoskeletal pain in Parkinson's disease: Association with dopaminergic deficiency in the caudate nucleus.

BACKGROUND: Musculoskeletal (MSK) pain affects over 80% of People with Parkinson's (PD, PwP) and may, in part, be dopaminergic in origin, as dopaminergic medication often leads to its relief. METHODS: PwP who underwent striatal dopamine transporter visualization with a radiopharmaceutical DaTscan™ (123 I-Ioflupane Injection) using a single-photon emission computed tomography (SPECT) as a part of their clinical-diagnostic work up were enrolled in the "Non-motor International Longitudinal Study" (NILS; UK National Institute for Health Research Clinical Research Network Number 10084) and included in this cross-sectional analysis. The association between specific DaTscan binding ratios for each striatum, the caudate nucleus and putamen and clinical ratings for MSK pain (assessed using the King's Parkinson's Disease Pain Scale (KPPS)) were analysed. RESULTS: 53 PwP (30.2% female; age: 63.79 ± 11.31 years; disease duration (DD): 3.32 (0.31-14.41) years; Hoehn & Yahr stage (H&Y): 2 (1-4); Levodopa Equivalent Daily Dose (LEDD): 543.08 ± 308.94 mg) were assessed and included in this analysis. MSK pain was highly prevalent (71.7% of all participants, mean KPPS Item 1 score 5.34 ± 4.76) and did not correlate with the motor symptoms burden (SCOPA-Motor total score; p = 0.783) but showed a significant correlation with quality of life (PDQ-8, rs = 0.290, p = 0.035). z-scores for the caudate nucleus (Exp (B) = 0.367, 95% CI for Exp (B) 0.148-0.910, p = 0.031) and striatum (Exp (B) = 0.338, 95% CI for Exp (B) 0.123-0.931, p = 0.036), adjusted for DD, H&Y and LEDD, were significant determinants of MSK pain. CONCLUSIONS: Our findings suggest an association between MSK pain in PwP and the severity of dopaminergic deficiency in the caudate nucleus. SIGNIFICANCE: In People with Parkinson's, musculoskeletal pain does not arise simply as a direct sequel to motor symptoms-instead, it is linked to the severity of dopaminergic depletion in the caudate nucleus.

Dynamic Monitoring of Probiotics Effect in Parkinson's Disease Patients via Swarm Decomposition and Bispectral Analysis of Electrogastrograms.

People with Parkinson's Disease (PwP) experience a significant deterioration of their daily life quality due to non-motor symptoms, with gastrointestinal dysfunctions manifesting as a vanguard of the latter. Electrogastrography (EGG) is a noninvasive diagnostic tool that can potentially provide biomarkers for the monitoring of dynamic gastric alterations that are related to daily lifestyle and treatment regimens. In this work, a robust analysis of EGG dynamics is introduced to evaluate the effect of probiotic treatment on PwP. The proposed framework, namely biSEGG, introduces a Swarm Decomposition-based enhancement of the EGG, combined with Bispectral feature engineering to model the underlying Quadratic Phase Coupling interactions between the gastric activity oscillatory components of EGG. The biSEGG features are benchmarked against the conventional Power Spectrum-based ones and evaluated through machine learning classifiers. The experimental results, when biSEGG was applied on data epochs from 11 PwP (probiotic vs placebo, AUROC: 0.67, Sensitivity/Specificity: 75/58%), indicate the superiority of biSEGG over Power Spectrum-based approaches and justify the efficiency of biSEGG in capturing and explaining intervention- and meal consumption-related alterations of the gastric activity in PwP.Clinical relevance- biSEGG holds potential for dynamic monitoring of gastrointestinal dysfunction and health status of PwP across diverse daily life scenarios.

Clinical trajectories and biomarkers for weight variability in early Parkinson's disease.

Unexplained weight changes that occur in Parkinson's disease (PD), are often neglected and remain a poorly understood non-motor feature in patients with PD. A specific 'Park-weight' phenotype with low body weight has been described, and our aim was to evaluate the clinical and prognostic trajectories and biomarkers of weight variability in PD. We evaluated body weight-related biomarkers in 405 de novo PD patients and 187 healthy controls (HC) over a 5-year follow-up period from the PPMI database. Body-weight variability was defined as intra-individual variability in body weight between visits. PD patients were categorized as weight losers, gainers, or patients with stable weight. The differential progression of motor and non-motor clinical variables between groups was explored using linear mixed-effects models. Finally, we estimated longitudinal changes in weight as a function of baseline and longitudinal striatal presynaptic dopaminergic transporter imaging. PD patients presented a greater weight variability compared to HC (p = 0.003). Patients who developed weight loss had lower CSF amyloid-beta 1-42 (p = 0.009) at baseline. In addition, patients with weight loss showed a faster cognitive decline (p = 0.001), whereas patients with weight gain showed a slower motor progression (p = 0.001), compared to patients with stable weight. Baseline right striatal denervation was a predictor of weight variability in both PD patients and HC (p < 0.001). Similarly, weight variability in PD patients was associated with the progression of right striatal denervation (p < 0.001). Weight variability and specifically weight loss are more frequent in PD compared to HC, and are associated with specific motor, non-motor and cognitive progression patterns. A greater CSF amyloid burden was present at baseline in patients with subsequent weight loss. Presynaptic dopaminergic imaging in the right striatum may serve as a predictor of future weight changes in PD and HC.

Ethnic Disparities in Treatment of Chronic Pain in Individuals with Parkinson's Disease Living in the United Kingdom.

Background: Over 80% people with Parkinson's disease (PD; PwP) live with chronic pain. Objective: Whether ethnic disparities in receipt of appropriate analgesia exist among PwP with chronic pain living in the United Kingdom (UK). Methods: A retrospective datamining of an existing King's PD Pain Questionnaire validation study dataset enrolling 300 PwP. Results: 69 PwP: 23 Black (57% female), 23 Asian (57% female) and 23 White (65% female) had similar pain burden on the King's PD Pain Scale. Significantly more White PwP (83%) received pain relief compared to Black (48%) and Asian (43%) PwP (p = 0.016). The difference was most evident for opioid analgesics (White 43% vs. Black 4% vs. Asian 4%, p ≤ 0.001). Conclusions: Ethnic disparities in the analgesic use among PwP with chronic pain living in the UK are evident in this retrospective analysis, prompting large-scale studies and reinforcement of interventions to tackle the impact ethnicity might have on the successful analgesia.

Self-reported periodontitis and C-reactive protein in Parkinson's disease: a cross-sectional study of two American cohorts.

Periodontitis triggers systemic repercussions, such as elevated levels of high-sensitive C-reactive protein (hs-CRP). This has never been studied within Parkinson's Disease (PD). The aim of this study is to compare hs-CRP levels of self-reported periodontitis cases versus cases without periodontitis in PD patients. Data from the National Health and Nutrition Examination Survey (2015-2016 and 2017-2018 waves) were analyzed. PD cases were identified through medication regimens and periodontitis cases through a validated self-report questionnaire. 51 participants were included (24 females, 27 males, with mean age of 62.96 (14.71)). While the self-reported periodontitis group presented elevated levels of circulating hs-CRP (5.36 vs. 1.99 mg/L, p = 0.031), the self-reported without periodontitis group presented higher lymphocyte levels (29.35 vs. 28.03%, p = 0.007). Blood levels of hs-CRP were significantly higher in PD cases with self-reported periodontitis. Apart from the lymphocyte levels, there were no other significant differences according to the self-reported periodontal status. Future studies shall explore this association using clinical measures.

The impact of nonmotor symptom burden on sexual function.

Sexual dysfunction (SD) is defined as a combination of reduction in libido, and problems with a person's ability to have sex. It is a frequent but neglected and poorly recognized nonmotor symptom (NMS) in Parkinson's disease (PD) which correlates with reduced quality of life (QoL). Hypersexuality forms another spectrum of SD and is an impulse control disorder (ICD) of behavior, which also affects the sexual desires of people with Parkinson's (PwP) and impacts their partner, family, and QoL. NMS occur in various forms and represents a range of symptoms, from cognitive dysfunction to pain and SD, and this chapter explores the relationship of comorbid NMS with SD and also how NMS, motor symptoms, and hypersexuality experienced by patients may impact sexual function in people with Parkinson's (PwP).