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

Salivation in Parkinson's disease: A scoping review

OBJECTIVES

We aimed to provide an overview of the available literature that includes both objective assessments (namely hypersalivation and hyposalivation) and the subjective experience (namely xerostomia and drooling) of salivary problems in patients with Parkinson's disease.

BACKGROUND

In patients with Parkinson's disease, there may be complaints of salivary problems such as xerostomia or drooling. This can have consequences for their oral health and quality of life. To date, systematic reviews have focused on drooling only.

MATERIALS AND METHODS

A literature search in 4 databases was performed up to 12 February 2021. Two researchers independently assessed studies for eligibility.

RESULTS

In total, 63 studies were included. The prevalence of self-reported xerostomia ranged from 49% to 77%, and that of self-reported drooling ranged from 5% to 80%. Ten articles reported a significantly lower mean salivary flow in patients with Parkinson's disease than in controls. None of the articles with both a control group and a patient group reported a significantly higher salivary flow in patients with Parkinson's disease. When questioned about subjective salivary problems, a significantly higher prevalence of both xerostomia (7 studies) and drooling (14 studies) was found in patients with Parkinson's disease than in controls. Patients with Parkinson's disease have a lower salivary flow rate and higher prevalence of both xerostomia and drooling than controls.

CONCLUSION

The complexity of salivary problems present in patients with Parkinson's disease necessitates a multidisciplinary approach in order to avoid mutually counteracting treatments from different healthcare professionals.

Swallow Safety and Laryngeal Kinematics: A Comparison of Dysphagia Between Parkinson's Disease and Cerebrovascular Accident

BACKGROUND

Cerebrovascular accident (CVA) and Parkinson's disease (PD) are well established etiologies of dysphagia. However, differing physiological mechanisms underlying dysphagia may exist between these two causes. There have been limited investigations specifically comparing dysphagia between these two groups. Comparing dysphagia presentation in two different populations may improve clinical expectations, guide treatment approaches, and inform future research.

OBJECTIVE

This study examined the differences in presentation of dysphagia between PD and CVA. Dysphagia presentation, swallow safety, and laryngeal kinematics were compared between two clinical cohorts. What factors best predicted airway invasion in each group were explored.

METHODS

110 swallow studies of individuals with PD and CVA who were referred for swallowing evaluation were obtained. Each video was analyzed for quantitative dysphagia presentation using the Videofluoroscopic Dysphagia Scale (VDS), swallow safety using the Penetration-Aspiration scale, and kinematic timings of the laryngeal vestibule (time-to-laryngeal vestibule closure [LVC] and closure duration [LVCd]).

RESULTS

Frequencies of penetration or aspiration were similar between groups. The PD group displayed significantly greater pharyngeal stage swallow impairment than CVA, with more frequent reduced laryngeal elevation and increased vallecular residue. The CVA group displayed significantly greater oral stage impairment, with prolonged oral transit times. Time-to-LVC was significantly prolonged and was the strongest predictor of airway invasion in the PD group, but not for CVA.

CONCLUSION

Similar airway invasion rates for PD and CVA indicate the importance of screening for dysphagia in PD. Laryngeal kinematics as significant contributors to airway invasion in PD but not for CVA highlight the need for further research into these mechanisms and for targeted treatment approaches to dysphagia.

Prevalence of Sialorrhea Among Amyotrophic Lateral Sclerosis Patients: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVES

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative motor neuron disease (MND), and sialorrhea is a known symptom in patients with ALS, which may cause a social embarrassment and discomfort. However, people do not pay attention to sialorrhea up to now. This study is aimed at conducting a systematic review and meta-analysis of the pooled prevalence of sialorrhea in ALS patients all around the world and raising awareness of salivation.

METHODS

We searched PubMed and EMBASE databases to obtain the comprehensive literatures which reported the prevalence of sialorrhea. We used AHRQ and NOS to evaluate the literature quality. Subgroup analyses were performed based on screening instruments and severity of sialorrhea. At the meantime, sensitivity analyses was also conducted to identify the source of heterogeneity.

RESULTS

A total of 17 eligible studies which included 21 groups of data reported prevalence of sialorrhea. The pooled prevalence of sialorrhea among ALS patients was 30.8% (95% CI: 20.0%-44.2%). For studies using ALSFRS-R, direct questioning, postal survey, and ALSSoL average and ALSFRS-R, the pooled prevalence of sialorrhea was 22.7%, 25.8%, 29.8% and 52.0% respectively. According to the severity of sialorrhea, the prevalence of mild, moderate, and severe sialorrhea were 25.1%, 11.2%, and 10.5%, respectively. And none of the studies alone had a significant effect on the overall prevalence of sialorrhea after we eliminated each study separately in sensitivity analyses.

CONCLUSIONS

Sialorrhea is a relatively common symptom in ALS patients with a comparatively high prevalence. In our study, we found that the prevalence of sialorrhea in ALS patients is relatively higher than the results based on direct questioning or postal survey. Therefore, we deduced that sialorrhea should be evaluated by more complex professional assessment scales to improve the quality of life and improve early prognosis of disease.

Gastrointestinal involvement in Parkinson's disease: pathophysiology, diagnosis, and management

Growing evidence suggests an increasing significance for the extent of gastrointestinal tract (GIT) dysfunction in Parkinson's disease (PD). Most patients suffer from GIT symptoms, including dysphagia, sialorrhea, bloating, nausea, vomiting, gastroparesis, and constipation during the disease course. The underlying pathomechanisms of this α-synucleinopathy play an important role in disease development and progression, i.e., early accumulation of Lewy pathology in the enteric and central nervous systems is implicated in pharyngeal discoordination, esophageal and gastric motility/peristalsis impairment, chronic pain, altered intestinal permeability and autonomic dysfunction of the colon, with subsequent constipation. Severe complications, including malnutrition, dehydration, insufficient drug effects, aspiration pneumonia, intestinal obstruction, and megacolon, frequently result in hospitalization. Sophisticated diagnostic tools are now available that permit more detailed examination of specific GIT impairment patterns. Furthermore, novel treatment approaches have been evaluated, although high-level evidence trials are often missing. Finally, the burgeoning literature devoted to the GIT microbiome reveals its importance for neurologists. We review current knowledge about GIT pathoanatomy, pathophysiology, diagnosis, and treatment in PD and provide recommendations for management in daily practice.

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.

Swallow Safety and Laryngeal Kinematics: A Comparison of Dysphagia Between Parkinson's Disease and Cerebrovascular Accident

BACKGROUND

Cerebrovascular accident (CVA) and Parkinson's disease (PD) are well established etiologies of dysphagia. However, differing physiological mechanisms underlying dysphagia may exist between these two causes. There have been limited investigations specifically comparing dysphagia between these two groups. Comparing dysphagia presentation in two different populations may improve clinical expectations, guide treatment approaches, and inform future research.

OBJECTIVE

This study examined the differences in presentation of dysphagia between PD and CVA. Dysphagia presentation, swallow safety, and laryngeal kinematics were compared between two clinical cohorts. What factors best predicted airway invasion in each group were explored.

METHODS

110 swallow studies of individuals with PD and CVA who were referred for swallowing evaluation were obtained. Each video was analyzed for quantitative dysphagia presentation using the Videofluoroscopic Dysphagia Scale (VDS), swallow safety using the Penetration-Aspiration scale, and kinematic timings of the laryngeal vestibule (time-to-laryngeal vestibule closure [LVC] and closure duration [LVCd]).

RESULTS

Frequencies of penetration or aspiration were similar between groups. The PD group displayed significantly greater pharyngeal stage swallow impairment than CVA, with more frequent reduced laryngeal elevation and increased vallecular residue. The CVA group displayed significantly greater oral stage impairment, with prolonged oral transit times. Time-to-LVC was significantly prolonged and was the strongest predictor of airway invasion in the PD group, but not for CVA.

CONCLUSION

Similar airway invasion rates for PD and CVA indicate the importance of screening for dysphagia in PD. Laryngeal kinematics as significant contributors to airway invasion in PD but not for CVA highlight the need for further research into these mechanisms and for targeted treatment approaches to dysphagia.

The effect of subthalamic deep brain stimulation on autonomic dysfunction in Parkinson's disease: clinical and electrophysiological evaluation

Introduction: Subthalamic nucleus (STN) deep brain stimulation (DBS) is an important option in the treatment of motor symptoms and fluctuations in patients with advanced Parkinson's disease (PD). In addition to the improvement in motor symptoms, many studies have reported changes in some non-motor symptoms (NMS) after STN DBS.Method: 61 patients (42 males) who underwent STN DBS with advanced PD and 24 healthy controls (15 males) were included in the study. Autonomic symptoms (orthostatic hypotension, sweating, salivation) were assessed with a semi-structured questionnaire. Sympathetic skin responses (SSR) were studied by electrophysiological examination within 3-6 months after STN DBS.Results: SSR latency and amplitude were found between the control group and preoperative patients (P ≤ 0.01; p = 0.01, respectively), and between preoperative and postoperative patients (P ≤ 0.01; P ≤ 0.01, respectively). There was a statistically significant difference between the control group and postoperative patients (p = 0.005; p = 0.029, respectively). Orthostatic hypotension (29%) and sweating (48%) improved, but there was no change in the salivation.Discussion: We think that STN DBS applied in PD has not only motor symptoms and fluctuations, but also corrects autonomic dysfunctions such as sweating disorders and orthostatic hypotension; SSR is more sensitive and reliable in detecting autonomic dysfunction, independent of motor symptoms and fluctuations.

Dysphagia Screening in Parkinson's Disease. A diagnostic accuracy cross-sectional study investigating the applicability of the Gugging Swallowing Screen (GUSS)

BACKGROUND

Simple water-swallowing screening tools are not predictive of aspiration and dysphagia in patients with Parkinson's Disease (PD). We investigated the diagnostic accuracy of a multi-texture screening tool, the Gugging Swallowing Screen (GUSS) to identify aspiration and dysphagia/penetration in PD patients compared to flexible endoscopic evaluation of swallowing (FEES).

METHODS

Swallowing function was evaluated in 51 PD participants in clinical 'on-medication' state with the GUSS and a FEES examination according to standardized protocols. Inter-rater reliability and convergent validity were determined and GUSS- and FEES-based diet recommendations were compared.

KEY RESULTS

Inter-rater reliability of GUSS ratings was high (r_s  = 0.8; p < 0.001). Aspiration was identified by the GUSS with a sensitivity of 50%, and specificity of 51.35% (PPV 28%, NPV 73%, LR+ 1.03, LR- 0.97), dysphagia/penetration was identified with 72.97% sensitivity and 35.71% specificity (PPV 75%, NPV 33.33%, LR+ 1.14, LR- 0.76). Agreement between GUSS- and FEES-based diet recommendations was low (r_s  = 0.12, p = 0.42) with consistent NPO (Nil per Os) allocation by GUSS and FEES in only one participant.

CONCLUSIONS AND INFERENCES

The multi-texture screening tool GUSS in its current form, although applicable with good inter-rater reliability, does not detect aspiration in PD patients with acceptable accuracy. Modifications of the GUSS parameters "coughing," "voice change" and "delayed swallowing" might enhance validity. The GUSS' diet recommendations overestimate the need for oral intake restriction in PD patients and should be verified by instrumental swallowing examination.

Protocols and assessment procedures in fiberoptic endoscopic evaluation of swallowing: an updated systematic review

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Assessments of neurological populations do not demonstrate standardization in swallowing videoendoscopy.

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Need for standardization of VED protocols for patient diagnosis and management.

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None of the studies used the same protocol.

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The quality of the studies varied widely mainly in their methodologies and protocols.

Introduction

Neurological alterations can generate swallowing disorders and fiberoptic endoscopic evaluation of swallowing is one of the tests performed for its diagnosis, as well as assistance in dysphagia management.

Objective

To identify and describe a fiberoptic endoscopic evaluation of swallowing standardized protocol for the neurological adult population and its stages.

Methods

Systematic review registered on the PROSPERO platform (CRD42018069428), carried out on the websites: MEDLINE, Cochrane Library and Scielo; published between 2009 and 2020. Randomized clinical trials, cross-sectional, and longitudinal studies were included. Two independent judges evaluated the study design and extracted the data from the selected studies. Doubts regarding inclusion or not of the studies were evaluated by a third judge. Scientific articles included were those with adult neurological remained patients with outcomes: (1) diagnosis of swallowing disorder (2) change in sensitivity in laryngeal region (3) penetration of food offered (4) aspiration of food offered.

Results

3724 articles were initially selected, after personalized search for patients with neurological alterations 101 studies remained. In the end, 21 qualitative studies from 2009 to 2020 remained in the systematic review and they were described in detail and compared. Seven articles used protocols of the institutions in which the research took place and four mentioned using the same protocol. The reliable reproducibility of the protocols is feasible only in three of the articles, even presenting different protocols.

Conclusion

There is no standard or validated protocol to assess the swallowing function of adults with neurological diseases.

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.

Non-pharmacological Treatment Challenges in Early Parkinson's Disease for Axial and Cognitive Symptoms: A Mini Review

Background: Parkinson's disease (PD) is now known to be a multisystemic heterogeneous neurodegenerative disease, including a wide spectrum of both motor and non-motor symptoms. PD patients' management must encompass a multidisciplinary approach to effectively address its complex nature. There are still challenges in terms of treating axial (gait, balance, posture, speech, and swallowing) and cognitive symptoms that typically arise with disease progression becoming poorly responsive to dopaminergic or surgical treatments.

Objective: The objectives of the study are to further establish the presentation of axial and cognitive symptoms in early PD [Hoehn and Yahr (H&Y) scale ≤ 2] and to discuss the evidence for non-pharmacological approaches in early PD.

Results: Mild and subtle changes in the investigated domains can be present even in early PD. Over the last 15 years, a few randomized clinical trials have been focused on these areas. Due to the low number of studies and the heterogeneity of the results, no definitive recommendations are possible. However, positive results have been obtained, with effective treatments being high-intensity treadmill and cueing for gait disturbances, high-intensity voice treatment, video-assisted swallowing therapy for dysphagia, and warm-up exercises and Wii Fit^TM training for cognition.

Conclusions: Considering the association of motor, speech, and cognitive function, future trials should focus on multidisciplinary approaches to combined non-pharmacological management. We highlight the need for a more unified approach in managing these “orphan” symptoms, from the very beginning of the disease. The concept “the sooner the better” should be applied to multidisciplinary non-pharmacological management in PD.

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.

Predictive clinical factors for penetration and aspiration in Parkinson's disease

BACKGROUND

Do the current swallow-specific subquestions of neurological diagnostic tools reflect the objective swallowing function in Parkinson's disease (PD) patients or are clinical factors superior to predict critical aspiration?

METHODS

In a cross-sectional, observational study a total of 119 Parkinson outpatients were examined clinically and by flexible-endoscopic evaluation of swallowing (FEES). Self-reported dysphagia by subquestions of the MDS-UPDRS and NMS questionnaire and history of subjective aspiration signs were collected.

KEY RESULTS

Nearly, all PD patients showed deglutition abnormalities in FEES (113/119) while only 12%-27% of them reported swallowing problems in the swallow-specific subquestions of neurological standard diagnostic tools (MDS-UPDRS and NMS-Quest), and the answers were heterogeneous and poorly reproducible. With a sensitivity of up to a maximum of 50%, self-reported dysphagia is therefore no reliable tool for identifying dysphagia in PD. While most clinical parameters were linked to dysphagia to some extent, logistic regression analysis revealed high age (Odds Ratio (OR) 1.1 in years, 95% CI 1.03-1.18, P < 0.01), gender (OR 0.3 for females, 95% CI 0.08-0.97, P = 0.04), and affirmed subjective aspiration signs (OR 8.6, 95% CI 3.05-26.52, P < 0.001) as the most significant predictors for critical dysphagia.

CONCLUSIONS AND INFERENCES

Self-perception of swallowing is no reliable tool for identifying dysphagia and questionnaires are insufficient for detecting previous aspiration. Consequent and specific asking for previous subjective aspiration signs is the single most important measure for identifying PD patients at risk for critical aspiration.

Parkinson's Disease and Current Treatments for Its Gastrointestinal Neurogastromotility Effects

PURPOSE OF REVIEW

Gastrointestinal disturbances are seen in nearly all patients with Parkinson's disease and lead to impaired quality of life, affect drug pharmacodynamics, and potentially worsen patient's existing motor fluctuations, leading to further disability. Recent evidence links abnormal accumulations of α-synuclein aggregates in the periphery (gut) as seen in the cortex which causes dysfunctions impacting every level of the gastrointestinal tract from the esophagus, to the stomach, small bowel, colon, and rectum and can even predate the onset of the central neurologic disorder itself. Many treatments exist for the clinical phenotypes that result from the autonomic dysfunction and neuropathy involved in this neurodegenerative disorder. The treatments for the gut dysfunction seen in Parkinson's disease (PD) depend on the specific area of the gastrointestinal tract affected. For dysphagia, behavioral therapies with speech pathology, neuromuscular electrical stimulation, or botulinum toxin injection may be helpful. For gastroparesis, domperidone may serve as an antiemetic while also blunting the hypotensive potential of Levodopa while new treatments such as ghrelin agonists may prove beneficial to help appetite, satiety, gastric emptying in those with constipation, and even improve constipation. Antibiotics such as rifaximin with poor systemic absorption may be used to treat small bacterial overgrowth also found in those with PD while the benefits of probiotics is yet to be determined. Finally, constipation in PD can be a reflection of pelvic floor dyssynergia, slow transit constipation, or both, thus treatments targeting the specific anorectal dysfunction is necessary for better outcomes.