Salivary production in Parkinson's disease

Parkinson's disease - The dentist's role as part of the healthcare team

Parkinson's disease is a neurodegenerative disease that results in patients exhibiting uncontrolled movements, changes in saliva production, and difficulty in swallowing and speech. Understanding the staging of the disease and the available therapies allows dentists to treat these patients safely and with compassion to meet their oral health care needs for an optimal quality of life. This appraisal discusses Parkinson's disease as it relates to clinically relevant facts to manage and treat the oral health care needs of these patients in the short and long term including general dental care recommendations. Important observations related to Parkinson's disease include disease causation,; stages, pharmacologic treatment, the effects on saliva, mastication, dysphagia, and aspiration pneumonia. Dental recommendations are made for the dentate, the partially edentulous, and the completely edentulous Parkinson's patients with a focus on late-stage concerns. Optimizing dental health will help maintain the quality of life as the disease progresses. In late stages of Parkinson's disease, dental treatment should focus on keeping the patient comfortable and out of pain.  While benign neglect is an often-used term, compassionate therapy in the late stages of Parkinson's disease is a more compelling term for defining the patient's needs.  Since dysphagia in Parkinson's patients has been underdiagnosed, neurologists must be aware of the important part that dentists play in the early diagnosis for these patients.  Early referral to a dentist is vital to mitigate the unfortunate consequence of the need for extensive dental care in late-stage patients.

Oral health experiences of people living with Parkinson's disease: a scoping review

Background and aim Parkinson's disease is the fastest growing and second most common progressive neurodegenerative condition in the UK; poised to represent a major societal and health care challenge. The scoping review aims to provide an overview of the literature on the oral health (OH) experiences of people living with Parkinson's, identifying current research gaps and future priorities.Method Search strategies included three electronic databases, two grey literature databases, relevant organisations, specialist journals and hand searching of the reference lists. A data extraction tool was developed and piloted.Results A total of 121 items were included in the review. Four themes were identified: OH impact, education and training, service delivery and wider impacts of OH for people with Parkinson's (PwP). The majority of studies included were cross-sectional in design, describing the OH status of PwP.Conclusion The majority of research to date has focused on OH impact. Areas for future research include use of qualitative studies exploring the experiences, attitudes and priorities of PwP and their care partners. Inclusion of medical, dental and allied health care professionals, together with people with lived experience, is required to develop, implement and evaluate interventions to support OH.

Drooling disrupts the brain functional connectivity network in Parkinson's disease

AIMS

This study aimed to investigate the causal interaction between significant sensorimotor network (SMN) regions and other brain regions in Parkinson's disease patients with drooling (droolers).

METHODS

Twenty-one droolers, 22 PD patients without drooling (non-droolers), and 22 matched healthy controls underwent 3T-MRI resting-state scans. We performed independent component analysis and Granger causality analysis to determine whether significant SMN regions help predict other brain areas. Pearson's correlation was computed between imaging characteristics and clinical characteristics. ROC curves were plotted to assess the diagnostic performance of effective connectivity (EC).

RESULTS

Compared with non-droolers and healthy controls, droolers showed abnormal EC of the right caudate nucleus (CAU.R) and right postcentral gyrus to extensive brain regions. In droolers, increased EC from the CAU.R to the right middle temporal gyrus was positively correlated with MDS-UPDRS, MDS-UPDRS II, NMSS, and HAMD scores; increased EC from the right inferior parietal lobe to CAU.R was positively correlated with MDS-UPDRS score. ROC curve analysis showed that these abnormal ECs are of great significance in diagnosing drooling in PD.

CONCLUSION

This study identified that PD patients with drooling have abnormal EC in the cortico-limbic-striatal-cerebellar and cortio-cortical networks, which could be potential biomarkers for drooling in PD.

Chaudhuri's Dashboard of Vitals in Parkinson's syndrome: an unmet need underpinned by real life clinical tests

We have recently published the notion of the "vitals" of Parkinson's, a conglomeration of signs and symptoms, largely nonmotor, that must not be missed and yet often not considered in neurological consultations, with considerable societal and personal detrimental consequences. This "dashboard," termed the Chaudhuri's vitals of Parkinson's, are summarized as 5 key vital symptoms or signs and comprise of (a) motor, (b) nonmotor, (c) visual, gut, and oral health, (d) bone health and falls, and finally (e) comorbidities, comedication, and dopamine agonist side effects, such as impulse control disorders. Additionally, not addressing the vitals also may reflect inadequate management strategies, leading to worsening quality of life and diminished wellness, a new concept for people with Parkinson's. In this paper, we discuss possible, simple to use, and clinically relevant tests that can be used to monitor the status of these vitals, so that these can be incorporated into clinical practice. We also use the term Parkinson's syndrome to describe Parkinson's disease, as the term "disease" is now abandoned in many countries, such as the U.K., reflecting the heterogeneity of Parkinson's, which is now considered by many as a syndrome.

Pharmacological Interventions for Sialorrhoea in People with Parkinson's Disease: A Systematic Review and Meta-Analysis

Background/objectives

Sialorrhoea is a common non motor complication experienced by people with Parkinson's disease (PD). Despite its prevalence there is conflicting evidence on how to effectively treat it. Our aim was to establish the efficacy and safety outcomes of pharmacological interventions used to treat sialorrhoea in people with idiopathic PD.

Methods

We registered and conducted a systematic review and meta-analysis (PROSPERO: CRD42016042470). We searched seven electronic databases from inception until July 2022. Quantitative synthesis was performed where data allowed using random effects models.

Results

From 1374 records we included 13 studies (n = 405 participants). Studies were conducted in Europe, North America and China. There was marked heterogeneity in the interventions used, follow up times and outcome measures investigated. The main source of risk of bias identified was reporting bias. Five studies were included in the quantitative synthesis. Summary estimates showed administration of botulinum toxin significantly reduced saliva production, improved patient reported functional outcomes and was associated with an increase in adverse events.

Conclusion

Sialorrhoea in PD is an important condition, but current data does not allow for strong recommendations on optimal pharmacological treatments. There is significant heterogeneity in outcomes measures used to evaluate the burden of sialorrhoea with lack of consensus on what constitutes clinically meaningful change. More research is required to better understand the underlying mechanism and potential treatments of sialorrhoea in idiopathic PD.

BoNT clinical trial update: Sialorrhea

Sialorrhea is the excessive accumulation of saliva, a prevalent symptom among a number of neurologic conditions in both pediatric and adult patients. Over the years, the management of sialorrhea has evolved and included a variety of interventions, ranging from nonpharmacologic, pharmacologic, and surgical treatment options. The most common option for treatment has been the use of botulinum toxin injections in the management of sialorrhea. While there have been several clinical trials to assess the efficacy of botulinum toxin in the treatment of sialorrhea, the largest randomized control trials to date have been with incobotulinumtoxin (2019) and rimabotulinumtoxin (2020) which show consistent reduction in salivary flow rate and improvement in clinical outcomes with comparable duration of treatment effectiveness. In this update, we review the evolution of treatment and injection methods for sialorrhea among many neurologic diseases. We discuss the challenges in evaluating and measuring efficacy in clinical trials for sialorrhea and compare the contemporary botulinum toxin clinical trials in the treatment of sialorrhea.

Possible role of endocannabinoids in olfactory and taste dysfunctions in Alzheimer's and Parkinson's patients and volumetric changes in the brain

The purpose of this study is to determine the volumes of primary brain regions associated with smell and taste in Alzheimer's and Parkinson's patients and healthy controls using MR imaging and examine volumetric changes in comparison to smell/taste questionnaire and test results and endocannabinoid (EC) levels. The study included 15 AD patients with mild cognitive dysfunction scored as 18 ≤ MMSE ≤ 23, 15 PD patients with scores of 18 < MoCA < 26 and 18 ≤ MMSE ≤ 23, and 15 healthy controls. A taste and smell questionnaire was given to the participants, and their taste and smell statuses were examined using the Sniffin' Sticks smell identification test and Burghart Taste Strips. EC levels were analyzed in the blood serum samples of the participants using the ELISA method. The volumes of the left olfactory bulb (p = 0.001), left amygdala (p = 0.004), left hippocampus (p = 0.008), and bilateral insula (left p = 0.000, right p = 0.000) were significantly smaller in the Alzheimer's patients than the healthy controls. The volumes of the left olfactory bulb (p = 0.001) and left hippocampus (p = 0.009) were significantly smaller in the Parkinson's patients than the healthy controls. A significant correlation was determined between volume reduction in the left Rolandic operculum cortical region and taste dysfunction. EC levels were significantly higher in both AD (p = 0.000) and PD (p = 0.006) in comparison to the controls. Our results showed that volumetric changes occur in the brain regions associated with smell and taste in Alzheimer's and Parkinson's patients. It was observed that ECs played a role in these volumetric changes and the olfactory and taste dysfunctions of the patients.

Pathophysiology and Symptomatology of Drooling in Parkinson’s Disease

Drooling can present in patients with Parkinson’s disease (PD), and it is manifested as an excessive pooling of saliva inside the oral cavity. Currently, the exact pathophysiological mechanism of drooling in PD is not yet fully explicated. Thus, it becomes crucial to understand if some clinical characteristics may emphasize drooling or if they are just concomitant. In PD, excessive drooling has been associated with a higher burden of non-motor symptoms, such as cognitive impairment, sleep problems, autonomic dysfunction, constipation and orthostatic hypotension, and of worse severity of motor fluctuations and bradykinesia. PD patients with excessive drooling also showed a reduction of striatal DAT availability at DaTSCAN imaging. Excessive drooling in patients with Parkinson’s cannot be attributed to a single factor but to a mixture of factors, including but not limited to impaired nigrostriatal pathways.

Gastrointestinal Dysfunction in Parkinson’s Disease: Current and Potential Therapeutics

Abnormalities in the gastrointestinal (GI) tract of Parkinson’s disease (PD) sufferers were first reported over 200 years ago; however, the extent and role of GI dysfunction in PD disease progression is still unknown. GI dysfunctions, including dysphagia, gastroparesis, and constipation, are amongst the most prevalent non-motor symptoms in PD. These symptoms not only impact patient quality of life, but also complicate disease management. Conventional treatment pathways for GI dysfunctions (i.e., constipation), such as increasing fibre and fluid intake, and the use of over-the-counter laxatives, are generally ineffective in PD patients, and approved compounds such as guanylate cyclase C agonists and selective 5-hyroxytryptamine 4 receptor agonists have demonstrated limited efficacy. Thus, identification of potential targets for novel therapies to alleviate PD-induced GI dysfunctions are essential to improve clinical outcomes and quality of life in people with PD. Unlike the central nervous system (CNS), where PD pathology and the mechanisms involved in CNS damage are relatively well characterised, the effect of PD at the cellular and tissue level in the enteric nervous system (ENS) remains unclear, making it difficult to alleviate or reverse GI symptoms. However, the resurgence of interest in understanding how the GI tract is involved in various disease states, such as PD, has resulted in the identification of novel therapeutic avenues. This review focuses on common PD-related GI symptoms, and summarizes the current treatments available and their limitations. We propose that by targeting the intestinal barrier, ENS, and/or the gut microbiome, may prove successful in alleviating PD-related GI symptoms, and discuss emerging therapies and potential drugs that could be repurposed to target these areas.

Salivary Heme Oxygenase-1: A Potential Biomarker for Central Neurodegeneration

BACKGROUND

Parkinson disease (PD) is the second most common neurodegenerative disease, affecting 2% of the population over 65 years of age. PD diagnosis is based on clinical examination and can only be confirmed during autopsy. In 2018, we reported that heme oxygenase-1 (HO-1), an inducible stress response protein important for heme catabolism and implicated in PD pathology, was higher in PD saliva relative to healthy controls, suggesting that salivary HO-1 may serve as a potential biomarker of PD.

OBJECTIVES

To ascertain whether HO-1 protein levels are elevated in PD saliva relative to degenerative neurological, non-degenerative neurological and healthy controls.

METHODOLOGY

The study included 307 participants comprising 75 participants with idiopathic PD and 3 control groups: 162 non-neurological, 37 non-PD degenerative neurological, and 33 non-degenerative neurological participants. Salivary HO-1 and total protein concentrations were measured using ELISA and BCA assay, respectively. Receiver operating characteristic (ROC) curves were used to estimate model discrimination. Analyses were adjusted by age, sex, total protein, and relevant comorbidities.

RESULTS

Elevated HO-1 concentrations were observed in the PD group and other neurodegenerative conditions compared to subjects with no neurological or non-degenerative neurological conditions. ROC curves using HO-1 levels and covariates yielded areas under the curve above 85% in models for PD or neurodegenerative conditions versus controls.

CONCLUSIONS

Salivary HO-1 concentrations in combination with covariates may provide a biomarker signature that distinguishes patients with neurodegenerative conditions from persons without.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that salivary HO-1 multivariable models can distinguish neurodegenerative conditions.

Aging-Related Metabolic Dysfunction in the Salivary Gland: A Review of the Literature

Aging-related salivary dysfunction commonly induces the poor oral health, including decreased saliva flow and dental caries. Although the clinical significance of the salivary glands is well-known, the complex metabolic pathways contributing to the aging-dysfunction process are only beginning to be uncovered. Here, we provide a comprehensive overview of the metabolic changes in aging-mediated salivary gland dysfunction as a key aspect of oral physiology. Several metabolic neuropeptides or hormones are involved in causing or contributing to salivary gland dysfunction, including hyposalivation and age-related diseases. Thus, aging-related metabolism holds promise for early diagnosis, increased choice of therapy and the identification of new metabolic pathways that could potentially be targeted in salivary gland dysfunction.

Impact of Progression of Parkinson's Disease on Swallowing Ability and Oral Environment

This study investigated the impact of the severity and treatment of Parkinson's disease (PD) on the swallowing ability and oral environment of patients. Swallowing dysfunction increases the aspiration risk and may lead to poor oral health among patients with PD. We investigated the influences of PD progression and drug treatment on the swallowing ability and oral environment using simple noninvasive screening measurements. We recruited 87 patients with PD (mean age, 71.9 ± 8.0 years; mean Hoehn and Yahr score, 2.9 ± 0.9). The PD condition was assessed in each patient using the unified Parkinson's disease rating scale (UPDRS) part III, diet type and oropharyngeal function using the swallowing disturbances questionnaire (SDQ), maximum bite force (MBF), tongue pressure (TP), and oral bacterial count (OBC). Levodopa equivalent daily dose (LEDD) was also calculated for 56 participants. Based on an SDQ score of ≥11, 29.5% of patients were dysphagic, but almost all were still on a regular diet. The SDQ score was positively correlated with disease duration (rho = 0.228, p=0.047) and UPDRS part III score (rho = 0.307, p=0.007) but was negatively correlated with OBC (rho = -0.289, p=0.012). OBC was significantly higher among patients with an SDQ score of <11 (nondysphagic) (p=0.01), and the SDQ score was lower in patients with higher OBC requiring professional oral care (p=0.03). However, OBC was also negatively correlated with LEDD (rho = -0.411, p=0.004). These results indicated low self-awareness of dysphagia among the participants and an association between dysphagia and PD progression. Moreover, the oral environment could have deteriorated with swallowing dysfunction. Patients and clinicians should be aware that higher LEDD can increase xerostomia and associated deficits in oral health.

Clinical features associated with drooling in Parkinson's disease

INTRODUCTION

Drooling is characterized by an excessive pooling of saliva in the oral cavity. The exact pathophysiological mechanism of drooling in Parkinson's disease (PD) is not yet fully understood.

OBJECTIVE

To identify the relationship between drooling and other clinical features in people diagnosed with PD.

METHOD

Research on the topic was carried out on the PubMed and ScienceDirect electronic databases. Articles published between March 2015 and March 2020 were selected. Search terms and inclusion and exclusion criteria were previously defined. The articles included met those requirements.

RESULTS

Sixteen articles were included for analysis. The prevalence of drooling varies between 9.26 and 70% and can occur at any stage of the disease. Higher prevalence of drooling is related to disease duration, disease severity, older age, male, levodopa equivalent dose, hypomimia, dysphagia, dysarthria, cognition, sleep, non-dominant tremor, motor fluctuations, bradykinesia, more symmetric pattern, gastrointestinal and urinary problems, sexual dysfunction, obstipation, and orthostatic hypotension. However, it is not related to hallucinations, rapid eye movement sleep behavior disorder, akinetic-rigid PD, mixed, nor dyskinesias.

CONCLUSION

Drooling is not caused by a single factor; it is influenced and related to several clinical features. Some clinical factors participate in the onset of drooling while others are concomitant.

Safety and Efficacy of RimabotulinumtoxinB for Treatment of Sialorrhea in Adults: A Randomized Clinical Trial

Question

Are rimabotulinumtoxinB injections safe and effective for management of sialorrhea in adults?

Findings

In this randomized clinical trial of 187 adults with sialorrhea, rimabotulinumtoxinB injections (2500 U and 3500 U) appeared to statistically significantly reduce sialorrhea vs placebo (treatment effect, −0.30 for both doses vs placebo, P < .001). Therapeutic benefits were seen as early as 1 week after injection and persisted for 11 to 15 weeks.

Meaning

RimabotulinumtoxinB is a safe, effective, and well-tolerated treatment for sialorrhea in adults.

Importance

RimabotulinumtoxinB (RIMA) may be preferable as an anti-sialorrhea treatment compared with current oral anticholinergic drugs in people with neurological disorders.

Objective

To assess the safety, efficacy, and tolerability of RIMA injections for the treatment of sialorrhea in adults.

Design, Setting, and Participants

This randomized, parallel, double-blind, placebo-controlled clinical trial of RIMA 2500 U and 3500 U was conducted from November 14, 2013, to January 23, 2017. A total of 249 adult patients with troublesome sialorrhea secondary to any disorder or cause were screened. Of them, 13 refused further participation in the study or were lost to follow-up and 49 did not fulfill the criteria for participation; 187 were ultimately enrolled. Patients had to have a minimum unstimulated salivary flow rate (USFR) of 0.2 g/min and a minimum Drooling Frequency and Severity Scale score of 4.

Exposures

Patients were randomized 1:1:1 to RIMA, 2500 U (n = 63); RIMA, 3500 U (n = 64); or placebo (n = 60).

Main Outcomes and Measures

Primary outcomes were the change in USFR from baseline to week 4 and the Clinical Global Impression of Change (CGI-C) at week 4. The CGI-C scores were recorded on a 7-point scale ranging from very much improved to very much worse. Adverse events were recorded throughout the trial period.

Results

Of 187 patients enrolled (147 men [78.6%]; mean [SD] age, 63.9 [13.3] years), 122 patients had Parkinson disease (65.2%), 13 (7.0%) were stroke survivors, 12 had amyotrophic lateral sclerosis (6.4%), 6 had medication-induced sialorrhea (3.2%), 4 had adult cerebral palsy (2.1%), and 30 had sialorrhea owing to other causes (16.0%). A total of 176 completed the study. Treatment with both doses of RIMA significantly reduced USFR at week 4 vs placebo (mean treatment difference, −0.30 g/min [95% CI, −0.39 to −0.21] for both doses vs placebo, P < .001). The CGI-C scores were statistically significantly improved at week 4 for both treatment groups vs placebo (−1.21 [95% CI, −1.56 to −0.87] for 2500 U, −1.14 [95% CI, −1.49 to −0.80] for 3500 U, both P < .001). Treatment benefits were seen as early as 1 week after injection and were maintained over the treatment cycle of approximately 13 weeks. The RIMA injections were well tolerated compared with placebo. The most common adverse events were self-limited mild to moderate dry mouth, dysphagia, and dental caries.

Conclusions and Relevance

Treatment with RIMA (2500 U and 3500 U) in adults was well tolerated and reduced sialorrhea, with the onset of the effect at 1 week after the injection. These data support the clinical use of RIMA in the management of sialorrhea in adults.

Trial Registration

ClinicalTrials.gov Identifier: NCT01994109

Cost-Effectiveness of IncobotulinumtoxinA in the Treatment of Sialorrhea in Patients with Various Neurological Conditions

INTRODUCTION

Sialorrhea is a common and debilitating symptom associated with neurological conditions, which can result in considerable physical and psychosocial complications. In Australia, management options are limited and further impeded by the lack of approved treatments. Whilst there is emerging evidence for the efficacy and tolerability of botulinum toxin (BoNT) for the treatment of sialorrhea in patients with neurological conditions, the cost-effectiveness of the treatment is yet to be established.

OBJECTIVES

To evaluate the cost-effectiveness of incobotulinumtoxinA for the treatment of chronic troublesome sialorrhea caused by various neurological conditions from the Australian healthcare perspective.

METHODS

A Markov state transition model was developed to perform a cost-utility analysis comparing incobotulinumtoxinA with standard of care (SoC). The model consisted of a hypothetical cohort of patients transiting between three severity-based health states, defined according to the Drooling Severity and Frequency Scale (DSFS), in 16-weekly cycles over 5 years. All clinical and utility inputs were sourced from a single placebo-controlled randomised clinical trial. Only direct healthcare costs were considered, and potential indirect costs such as carer's time and lost productivity were ignored. The primary outcome measure was the incremental cost per quality-adjusted life-year (QALY). Univariate and probabilistic sensitivity analyses were conducted.

RESULTS

The model demonstrated that proportionally more patients spent time in less severe sialorrhea health states in the incobotulinumtoxinA arm. For example, over the 5-year period, patients receiving incobotulinumtoxinA were estimated to spend 1.6 years with minimal or no sialorrhea, while no patients achieved this level of improvement under SoC. IncobotulinumtoxinA was shown to have an incremental cost per QALY gained of A$23,445 when compared with SoC.

CONCLUSIONS

The quality of life (QoL) of patients with sialorrhea caused by neurological conditions was considerably compromised. IncobotulinumtoxinA was shown to successfully alleviate sialorrhea and it was demonstrated to be a cost-effective intervention when compared with SoC alone.

A comprehensive review of the diagnosis and treatment of Parkinson's disease dysphagia and aspiration

INTRODUCTION

Bulbar dysfunction is common in Parkinson's disease (PD) with more than 80% of affected individuals developing dysphagia during the course of the disease. Symptoms can begin in the preclinical stage and individuals may remain clinically asymptomatic for years. Furthermore, patients may be unaware of swallowing changes, which contributes to the difference between the prevalence of self-reported dysphagia and deficits identified during instrumental evaluations. Dysphagia is underrecognized and contributes to the development of aspiration pneumonia which is the leading cause of death in PD. Dysphagia in PD is complex and not completely understood. Both dopaminergic and nondopaminergic pathways likely underpin dysphagia.

AREAS COVERED

This comprehensive review will cover the epidemiology, pathophysiology, clinical evaluation, and expert management of dysphagia and aspiration in patients with PD.

EXPERT OPINION

A multidisciplinary team approach is important to properly identify and manage PD dysphagia. Regular clinical screenings with objective instrumental assessments are necessary for early detection of dysphagia. Studies are needed to better understand the mechanism(s) involved in PD dysphagia, establish markers for early detection and progression, and develop evidence-based treatment options.

Relationships of drooling with motor symptoms and dopamine transporter imaging in drug-naïve Parkinson's disease

OBJECTIVES

The aim of the present study was to determine the relationships of drooling with motor symptoms and nigrostriatal neuron loss in drug-naïve patients with Parkinson's disease (PD). We therefore examined the relationships of drooling with motor symptoms and striatal dopamine transporter (DAT) binding measured by [123-Iodine]-fluoropropyl-2beta-carbomethoxy-3beta-(4-iodophenylnortropane) dopamine transporter single-photon emission computed tomography(¹²³I-FP-CIT SPECT).

PATIENTS AND METHODS

Thirty-five untreated PD patients (14 men and 21 women with a mean age of 71.9 ± 7.2 years) were included in this study. The patients were divided into a drooler group and non-drooler group. They underwent clinical assessments and ¹²³I-FP-CIT SPECT imaging. Motor symptoms were assessed using Unified Parkinson's Disease Rating Scale (UPDRS).

RESULTS

The results showed that UPDRS motor score (p = 0.002) and akinetic-rigid score (p = 0.008) were higher and that striatal DAT availability (p = 0.03) was lower in the drooler group than in the non-drooler group. However, tremor score, age, and duration of PD showed no significant differences between the drooler group and non-drooler group.

CONCLUSIONS

Drooling in untreated PD is related to an increase in motor symptoms (especially bradykinesia and axial symptoms) and to reduction of striatal DAT availability.

Drooling in Parkinson's Disease: Prevalence and Progression from the Non-motor International Longitudinal Study

Sialorrhoea in Parkinson’s disease (PD) is an often neglected yet key non-motor symptom with impact on patient quality of life. However, previous studies have shown a broad range of prevalence figures. To assess prevalence of drooling in PD and its relationship to quality of life, we performed a retrospective analysis of 728 consecutive PD patients who had a baseline and follow-up assessment as part of the Non-motor International Longitudinal Study (NILS), and for whom drooling presence and severity were available, assessed through the Non-Motor Symptoms Scale (NMSS). In addition, we analysed the prevalence of associated dysphagia through self-reported outcomes. Quality of life was assessed through the PDQ-8 scale. Baseline (disease duration 5.6 years) prevalence of drooling was 37.2% (score ≥ 1 NMSS question 19), and after 3.27 ± 1.74 years follow-up, this was 40.1% (p = 0.17). The prevalence of drooling increased with age (p < 0.001). The severity of drooling, however, did not change (p = 0.12). While in 456 patients without drooling at baseline, only 16% (n = 73) had dysphagia (question 20 of the NMSS), in those with drooling this was 34.3% (p < 0.001). At follow-up, the number of patients with dysphagia had increased, 20.4% with no drooling had dysphagia, and 43.6% with drooling had dysphagia. Both at baseline and follow-up, drooling severity was significantly positively associated with quality of life (PDQ-8; r = 0.199; p < 0.001). In moderately advanced PD patients, subjective drooling occurs in over one-third of patients and was significantly associated with decreased quality of life. Dysphagia occurred significantly more often in patients with drooling.

The feasibility and acceptability of using a novel wrist worn cueing device to self-manage drooling problems in people with Parkinson's disease: A pilot study

Introduction

Daytime drooling is experienced by around 50% of Parkinson’s patients, who fail to swallow saliva in sufficient volume or regularity, despite normal production. This research explored the feasibility and acceptability of using a cueing device, to improve drooling.

Methods

During a four-week intervention, 28 participants were asked to use a cueing device for 1 h per day. During this time, the device vibrated once-per-minute, reminding the participant to swallow their saliva. A daily diary was used to collect self-report around swallowing severity, frequency, and duration. This was filled out by participants for one week before, four weeks during and for one week immediately after intervention. Diaries were also collected for one week during a follow up, carried out four weeks after intervention finished.

Results

Participants self-reported benefits in drooling severity (p = 0.031), frequency (p ≤ 0.001), and duration (p = 0.001) after using the device. Improvements were maintained at follow up. Twenty-two participants explicitly reported a positive benefit to their drooling during exit interview. All felt the intervention and device were acceptable and usable.

Conclusions

Using a cueing device for one month had perceived benefit to drooling severity, frequency and duration in patients with Parkinson’s. Participants accepted the device and treatment protocol.

Alpha-synuclein in salivary gland as biomarker for Parkinson’s disease

Estimates of the accuracy of clinical diagnosis of Parkinson’s disease (PD) range between 46% and 90%, the accuracy of diagnosis dependent on prolonged clinical observation and clinical response to levodopa. For this reason, we need reliable diagnostic biomarkers. The cardinal hallmark of PD is alpha-synuclein aggregation in the brain. Demonstrating pathological alpha-synuclein in live patients would be useful for identifying and monitoring PD patients. By autopsy studies and in vivo studies, the presence of alpha-synuclein has been demonstrated even outside the central nervous system and the gastro-enteric tract appears to be the most promising candidate tissue for biopsy-taking and the esophagus and salivary glands appear to be the area with the highest concentration of alpha-synuclein. The purpose of our study is to conduct a review to determine the utility of salivary gland biopsy for the histological diagnosis of PD. A computerized medline study was carried out through the use of pubmed: using the MeSH terms: ‘salivary gland biopsy for PD’, ‘PD and dysphagia’, ‘alpha-synuclein and salivary gland’. We found 9 articles about minor salivary glands and submandibular gland biopsy for diagnosis of PD. According to the results of this review, the submandibular gland biopsy is the test with the increased sensitivity and specificity compared to the biopsy of the minor salivary glands (sensitivity: 0.85 and 0.37 respectability and specificity: 0.96 and 0.94 respectively). New studies are necessary on a wider population to confirm these results.

Frequency and factors related to drooling in Chinese patients with multiple system atrophy: a cross-sectional study

PURPOSE

Drooling is a common symptom of neurodegenerative diseases. We aimed to explore the frequency of drooling and its relationship to clinical features in a relatively large cohort of Chinese patients with multiple system atrophy (MSA).

METHODS

We conducted a cross-sectional survey of 143 patients with MSA. Patients with drooling were identified as those with a score ≥ 1 on item 6 of the Unified Parkinson's Disease Rating Scale. Additional scales were used to rate daily functionality, neurologic and cognitive capabilities, levels of anxiety and depression, and sleep quality. These results were compared between patients with and without drooling.

RESULTS

The frequency of drooling in this cohort was 59.4% (85/143). Drooling was associated with significantly poorer scores on the Unified MSA Rating Scale (subscore I, subscore II, subscore IV, total score), Pittsburgh Sleep Quality Index, Hamilton Depression Scale, Hamilton Anxiety Scale, and Mini-Mental State Examination. After adjusting for confounders, regression analysis identified two independent risk factors for drooling: parkinsonism-associated MSA (OR 2.54, 95% CI 1.15-5.65) and hypomimia (OR 3.18, 95% CI 1.32-7.68).

CONCLUSIONS

Drooling is relatively common among Chinese MSA patients, and parkinsonism-associated MSA and hypomimia appear to be independent risk factors for drooling. The severity of this symptom correlates with the presence of severe motor symptoms, anxiety, depression, and sleep disorders.

Autonomic dysfunction in Parkinson disease and animal models

Parkinson disease has traditionally been classified as a movement disorder, despite patients' accounts of diverse symptoms stemming from impairments in numerous body systems. Today, Parkinson disease is increasingly recognized by clinicians and scientists as a complex neurodegenerative disorder featuring both motor and nonmotor manifestations concomitant with pathology throughout all major branches of the nervous system. Dysfunction of the autonomic nervous system, or dysautonomia, is a common feature of Parkinson disease. It produces signs and symptoms that severely affect patients' quality of life, such as blood pressure dysregulation, hyperhidrosis, and constipation. Treatment options for dysautonomia are limited to symptom alleviation because the cause of these symptoms and Parkinson disease overall are still unknown. Animal models provide a platform to interrogate mechanisms of Parkinson disease-related autonomic nervous system dysfunction and test novel treatment strategies. Several animal models of Parkinson disease are available, each with different effects on the autonomic nervous system. This review critically analyses key dysautonomia signs and symptoms and associated pathology in Parkinson disease patients and relevant findings in animal models. We focus on the cardiovascular system, adrenal medulla, skin/thermoregulation, bladder, pupils, and gastrointestinal tract, to assess the contribution of animal models to the understanding of Parkinson disease autonomic dysfunction.

Incobotulinumtoxin A for Sialorrhea in Neurological Disorders: A Real-Life Experience

Botulinum toxin type A is one of the most useful treatments of sialorrhea in neurological disorders. Evidence for the use of incobotulinumtoxin A (inco-A) in the treatment of sialorrhea is limited. Thirty-six patients with sialorrhea were treated with infiltrations of inco-A into both parotid glands. The severity of sialorrhea was evaluated by the Drooling Severity Scale (DSS), and the Drooling Frequency Scale (DFS). Patients’ perceptions of clinical benefit were recorded via the Patient Global Impression of Improvement (PGI-I) scale. Following treatment, there was a significant difference in both the DFS and the DSS (p < 0.001). Clinical benefits on the basis of the PGI-I were present in up to 90% of patients.

Salivary biomarkers for the diagnosis and monitoring of neurological diseases

Current research efforts on neurological diseases are focused on identifying novel disease biomarkers to aid in diagnosis, provide accurate prognostic information and monitor disease progression. With advances in detection and quantification methods in genomics, proteomics and metabolomics, saliva has emerged as a good source of samples for detection of disease biomarkers. Obtaining a sample of saliva offers multiple advantages over the currently tested biological fluids as it is a non-invasive, painless and simple procedure that does not require expert training or harbour undesirable side effects for the patients. Here, we review the existing literature on salivary biomarkers and examine their validity in diagnosing and monitoring neurodegenerative and neuropsychiatric disorders such as autism and Alzheimer's, Parkinson's and Huntington's disease. Based on the available research, amyloid beta peptide, tau protein, lactoferrin, alpha-synuclein, DJ-1 protein, chromogranin A, huntingtin protein, DNA methylation disruptions, and micro-RNA profiles provide display a reliable degree of consistency and validity as disease biomarkers.

Drooling is no early sign of dysphagia in Parkinson's disease

BACKGROUND

Dysphagia is frequent and clinically highly relevant in Parkinson's disease (PD). For a rational dysphagia screening predictors are required. Previous investigations suggested that drooling correlates with dysphagia and may serve as its early sign. The aim of this study was to clarify the interrelationship of drooling and dysphagia.

METHODS

In a controlled, cross-sectional, observational study, a total of 119 Parkinson outpatients and 32 controls were examined clinically and by flexible-endoscopic evaluation of swallowing (FEES). Drooling, dysphagia including retained pharyngeal secretions, and cognitive function were assessed by established evaluation scales.

KEY RESULTS

Fifty percent of all PD patients but only 9% of controls had drooling (P < .001). Drooling and dysphagia were related in PD (P = .027) but the data do not support to view drooling as a hallmark symptom for critical dysphagia. Thirty-nine percent of the patients with critical aspiration had no drooling. In contrast, 41% of the patients with severe drooling had no clinically relevant dysphagia in FEES. The oral, but not the pharyngeal secretion management was impaired in PD patients and there was no clear association between drooling and pharyngeal secretion accumulation. Cognitive impaired patients had significantly more drooling (P = .005).

CONCLUSIONS & INFERENCES

Although frequent in PD, drooling and dysphagia are only weakly related and drooling cannot be viewed as an early sign of dysphagia. Our data further suggest that the underlying cause of drooling is located in the voluntary oral phase, which is negatively influenced by cognitive deficits.

Alpha-synuclein is present in dental calculus but not altered in Parkinson's disease patients in comparison to controls

INTRODUCTION

In autopsy cases staged for sporadic Parkinson's disease (PD), the neuropathology is characterized by a preclinical phase that targets the enteric nervous system of the gastrointestinal tract (GIT). Therefore, the ENS might be a source of potential (presymptomatic) PD biomarkers.

METHODS

In this clinically based study, we examined the alpha-synuclein (αSyn) concentration in an easily accessible protein storage medium of the GIT, dental calculus, in 21/50 patients with PD and 28/50 age- and gender-matched controls using ELISA.

RESULTS

αSyn was detectable in dental calculus and the median concentration in the control patients was 8.6 pg/mg calculus (interquartile range 2.6-13.1 pg/mg). αSyn concentrations were significantly influenced by blood contamination and samples with a hemoglobin concentration of > 4000 ng/mL were excluded. There was no significant difference of αSyn concentrations in the dental calculus of PD patients (5.76 pg/mg, interquartile range 2.91-9.74 pg/mg) compared to those in controls (p = 0.40).

CONCLUSION

The total αSyn concentration in dental calculus is not a suitable biomarker for sporadic PD. Disease-related variants such as oligomeric or phosphorylated αSyn in calculus might prove to be more specific.

Evaluation of salivary heme oxygenase-1 as a potential biomarker of early Parkinson's disease

BACKGROUND AND HYPOTHESIS

To date, there are no chemical analytes, including biochemical indices of oxidative stress, metabolites of α-synuclein protein, and differential protein expression patterns on proteomic profiling, for use in clinics as a diagnostic biomarker of idiopathic PD.

OBJECTIVES

Heme oxygenase-1 has been implicated in the pathogenesis of PD. The objective of this study is to ascertain whether salivary heme oxygenase-1 may serve as a biomarker for early idiopathic PD.

METHODS

Fifty-eight PD patients and 59 non-neurological disease controls were recruited. Levels of heme oxygenase-1 expression were assayed using enzyme-linked immunosorbent assay and western blot analysis of whole, unstimulated saliva. Analyses were adjusted by sex, l-dopa exposure, and relevant comorbidities.

RESULTS

We documented: (1) the presence of 32-kDa heme oxygenase-1 protein in human saliva; (2) significantly higher mean heme oxygenase-1 protein concentrations in saliva of PD patients relative to control values; (3) no variability in salivary heme oxygenase-1 levels with sex, age, l-dopa equivalence, or comorbidities; and (4) significantly higher mean salivary heme oxygenase-1 concentrations in patients with H & Y stage 1 PD (early) than control subjects and stage 2 and stage 3 PD patients. The area under the receiver operating characteristic curve that separated controls from PD H & Y stage 1 was 76% (95% confidence interval: 63-90).

CONCLUSIONS

Salivary heme oxygenase-1 concentrations may provide a useful, noninvasive, and relatively inexpensive biomarker of early idiopathic PD. © 2018 International Parkinson and Movement Disorder Society.

Dopaminergic Therapies for Non-motor Symptoms in Parkinson's Disease

Apart from the typical motor symptoms, Parkinson's disease is characterized by a wide range of different non-motor symptoms, which are highly prevalent in all stages of the disease and have an incisive influence on quality of life. Moreover, their treatment continues to be challenging. In this review, we critically summarize the evidence for the impact of dopaminergic therapies on non-motor symptoms in Parkinson's disease. We performed a PubMed search to identify relevant clinical studies that investigated the response of non-motor symptoms to dopaminergic therapy. In the domain of neuropsychiatric disturbances, there is increasing evidence that dopamine agonists can ameliorate depression or anxiety. Other neuropsychiatric symptoms such as psychosis or impulse control disorders can also be worsened or even be induced by dopaminergic agents. For the treatment of sleep disturbances, it is essential to identify different subtypes of sleep pathologies. While there is for example profound evidence for the effectiveness of dopaminergic medication for the treatment of restless legs syndrome and sleep fragmentation, evidence for an improvement of rapid eye movement sleep behavior disorder is lacking. With regard to the broad spectrum of autonomic disturbances, response to dopaminergic treatment seems to differ largely, with on the one hand, some evidence for an improvement of sexual function or sweating with dopaminergic treatment, while on the other hand, constipation can be worsened. Finally, the analysis of sensory deficits reveals that some forms of pain, in particular fluctuation-dependent dystonic pain, can be well addressed by adapting the dopaminergic therapy, while no effect has been seen so far for hyposmia or visual deficits. Moreover, the occurrence of non-motor fluctuations is gaining increased attention, as they can be specifically addressed by a more continuous dopaminergic intake. Taken together, there is evidence of a good response of some (but not all) non-motor symptoms to dopaminergic therapy, which must be individually adapted to the special spectrum of symptoms.

Part 3: Impact of systemic conditions and medications on oral health

The people who are treated in the community setting will often have multiple comorbidities. Systemic medical conditions can have a negative impact on oral health. In addition, the medications used to treat systemic conditions may also themselves cause oral symptoms. As a large proportion of patients treated by the community nursing team will be elderly, this paper will focus on common geriatric conditions that can display oral or dental symptoms. The effects of medications will be discussed and linked to oral complaints patients may express. The primary aims are to give a broad overview of the oral effects of ageing, of illness and of polypharmacy and advise on how these can be best managed by the nursing team.

Gastrointestinal Dysfunctions in Parkinson's Disease: Symptoms and Treatments

A diagnosis of Parkinson's disease is classically established after the manifestation of motor symptoms such as rigidity, bradykinesia, and tremor. However, a growing body of evidence supports the hypothesis that nonmotor symptoms, especially gastrointestinal dysfunctions, could be considered as early biomarkers since they are ubiquitously found among confirmed patients and occur much earlier than their motor manifestations. According to Braak's hypothesis, the disease is postulated to originate in the intestine and then spread to the brain via the vagus nerve, a phenomenon that would involve other neuronal types than the well-established dopaminergic population. It has therefore been proposed that peripheral nondopaminergic impairments might precede the alteration of dopaminergic neurons in the central nervous system and, ultimately, the emergence of motor symptoms. Considering the growing interest in the gut-brain axis in Parkinson's disease, this review aims at providing a comprehensive picture of the multiple gastrointestinal features of the disease, along with the therapeutic approaches used to reduce their burden. Moreover, we highlight the importance of gastrointestinal symptoms with respect to the patients' responses towards medical treatments and discuss the various possible adverse interactions that can potentially occur, which are still poorly understood.

Gastrointestinal Dysmotility in the Elderly

The number of persons 60 years and older has increased 3-fold between 1950 and 2000. Aging alone does not greatly impact the gastrointestinal (GI) tract. Digestive dysfunction, including esophageal reflux, achalasia, dysphagia, dyspepsia, delayed gastric emptying, constipation, fecal incontinence, and fecal impaction, is a result of the highly prevalent comorbid conditions and the medications with which those conditions are treated. A multidisciplinary approach with the expertise of a geriatrician, gastroenterologist, neurologist, speech pathologist, and physical therapist ensures a comprehensive functional and neurological assessment of the older patient. Radiographic and endoscopic evaluation may be warranted in the evaluation of the symptomatic older patient with consideration given to the risks and benefits of the test being used. Treatment of the digestive dysfunction is aimed at improving health-related quality of life if cure cannot be achieved. Promotion of healthy aging, treatment of comorbid conditions, and avoidance of polypharmacy may prevent some of these digestive disorders. The age-related changes in GI motility, clinical presentation of GI dysmotility, and therapeutic principles in the symptomatic older patient are reviewed here.

A resting-state fMRI study on early-stage drug-naïve Parkinson's disease patients with drooling

OBJECTIVE

Drooling is a common symptom in Parkinson's disease (PD). This study used resting-state functional MRI (fMRI) to evaluate the brain connectivity of cortico-striatal circuits in PD patients with drooling.

METHOD

We enrolled 30 early-stage drug-naïve PD patients and 30 matched normal controls. Among the PD patients, 15 patients were classified as "droolers" with the presence of drooling and 15 patients as "non-droolers" with the absence of drooling. All participants underwent resting-state fMRI scans on a 3-T MR system, focusing on the functional connectivity of striatum subregions.

RESULTS

Compared with PD patients without drooling, PD patients with drooling showed the significantly reduced functional connectivity of putamen within bilateral sensorimotor cortices, superior and inferior parietal lobules and areas in the right occipital and temporal lobes. No increased functional connectivity was found between the two PD subgroups. In addition, compared with healthy controls, both PD subgroups showed the functional connectivity alterations in cortico-striatal loops. The decreased functional connectivity was prominent in the most affected posterior putamen, and the increased functional connectivity was evident only in the relatively unaffected anterior striatum and caudate.

CONCLUSION

By studying a cohort of early-stage drug-naïve PD patients, we eliminated the potential confounding effects of antiparkinson medication on the functional integration of neural networks. We demonstrated decreased connectivity within cortico-striatal networks in PD patients with drooling. These findings might be helpful for promoting the further understanding of neural system effects underlying drooling in PD. Our result is preliminary and further investigation is needed.

Gut dysfunction in Parkinson's disease

Early involvement of gut is observed in Parkinson’s disease (PD) and symptoms such as constipation may precede motor symptoms. α-Synuclein pathology is extensively evident in the gut and appears to follow a rostrocaudal gradient. The gut may act as the starting point of PD pathology with spread toward the central nervous system. This spread of the synuclein pathology raises the possibility of prion-like propagation in PD pathogenesis. Recently, the role of gut microbiota in PD pathogenesis has received attention and some phenotypic correlation has also been shown. The extensive involvement of the gut in PD even in its early stages has led to the evaluation of enteric α-synuclein as a possible biomarker of early PD. The clinical manifestations of gastrointestinal dysfunction in PD include malnutrition, oral and dental disorders, sialorrhea, dysphagia, gastroparesis, constipation, and defecatory dysfunction. These conditions are quite distressing for the patients and require relevant investigations and adequate management. Treatment usually involves both pharmacological and non-pharmacological measures. One important aspect of gut dysfunction is its contribution to the clinical fluctuations in PD. Dysphagia and gastroparesis lead to inadequate absorption of oral anti-PD medications. These lead to response fluctuations, particularly delayed-on and no-on, and there is significant relationship between levodopa pharmacokinetics and gastric emptying in patients with PD. Therefore, in such cases, alternative routes of administration or drug delivery systems may be required.

Visuomotor control of neck surface electromyography in Parkinson's disease

OBJECTIVE

To compare performance of individuals with Parkinson's disease (PD) and age-matched controls on a visuomotor tracking task controlled via surface electromyography (sEMG).

METHODS

Twenty-seven adults with PD and twenty-four older controls produced dry swallows and completed a visuomotor tracking task utilizing both static and dynamic targets. sEMG was recorded at the anterior neck and submental surface during both tasks.

RESULTS

There was no significant difference in visuomotor tracking ability between cohorts. Post hoc analyses indicated that there was no significant difference between participant groups in the strength or duration of swallows as measured by sEMG but that participants with PD showed a trend for decreased swallow durations at the anterior neck (padj = 0.067) whereas controls showed a trend for increased durations at the anterior neck (padj = 0.112), compared to the submental surface. However, there were no significant correlations between swallowing behavior and visuomotor tracking ability.

CONCLUSION

There were no significant differences in visuomotor tracking performance between individuals with PD and controls. Furthermore, there was no relationship between tracking ability and swallowing behavior. We conclude that sEMG-mediated biofeedback may have limited promise as a tool for treating PD-related dysphagia.

Hypersialorrhea in Wilson's Disease

Hypersialorrhea, corresponding to excessive salivation is a symptom frequently reported in Wilson's disease, especially in its neurological form. The prevalence of this frequent complaint has not been often evaluated. During a 7-month period, 87 consecutive Wilson's disease patients answered to the simple question "do you have the sensation of excess saliva in your mouth?" to evaluate the frequency of this symptom. A sub-sample of 10 consecutive Wilson's disease patients with drooling was recruited to undergo quantitative and qualitative measures to evaluate the mechanism of hypersialorrhea. Excessive drooling or excess saliva was found in 46 % of patients followed at the French Reference Centre. Ninety-eight percent of them presented neurological symptoms and drooling was found in only one patient without neurological symptoms. Our study showed that patients with a complaint of excessive saliva produced significantly higher quantities of saliva at rest than controls. Endoscopic examination was abnormal in six patients. A significant decrease of swallowing frequency, longer swallow latencies, and poor swallowing capacities may partly explain the salivary stasis. Oropharyngeal sensitivity disorders were present in 50 % of our patients. The decrease of the swallowing frequency observed in all patients could be related to cognitive and behavioral abnormalities with initiation difficulties objectified by longer latencies triggered by all the ingested volumes. This study confirmed the hypothesis of a multifactorial origin of hypersialorrhea in patients who have been diagnosed in Wilson's disease. It was essential to evaluate drooling with a multidisciplinary consultation to better identify the underlying mechanisms and to implement strategies for speech therapy and therapeutic adaptation.

The option of sonographic guidance in Botulinum toxin injection for drooling in Parkinson's disease

Parkinson's disease is a syndrome that frequently includes drooling, i.e., the involuntary spillage of saliva over the lip margin. Such drooling places a severe burden on both the health and the quality of life of Parkinsonian patients. Its origin lies in the impairment of oral motor control and swallowing associated with Parkinson's disease. It can be treated surgically or conservatively by reducing the production of saliva in the salivary glands, to which the parotid and submandibular glands make the greatest contribution. Botulinum neurotoxins A and B, administered to these glands, are in increasing use as treatment for drooling from various causes including Parkinson's disease. Wide knowledge was gathered about preferred drugs, dosages, injection sites and injection-guiding techniques, albeit without providing evidence-based guidance or a clear rationale for the mode of action of the medication or any information about further influential or predictive factors for safety and efficacy. However, it is essential that the relevant glands be targeted accurately; although this can be done by using anatomical landmarks, the use of sonographic guidance seems preferable. In the hands of a trained injector, sonography is a quick and non-invasive imaging technique.