Esophageal dysfunction in different stages of Parkinson's disease

Pharyngeal adaptation to bolus properties in patients with Parkinson's disease

PURPOSE

Dysphagia is common in people with Parkinson's disease (PD). Yet, literature describing swallow function in PD using high-resolution manometry is limited. This study explored swallowing pressure metrics for varied bolus conditions in people with PD.

METHOD

A solid-state unidirectional catheter was used to acquire manometric data for triplicate swallows (5 ml, 10 ml, 20 ml; IDDSI 0, 2 & 4). Penetration-aspiration severity was rated during videofluoroscopy. Patient-reported measures included PDQ-8: Parkinson's Disease Questionnaire-8 and EAT-10: Eating Assessment Tool-10. Quantitative manometric swallow analysis was completed through Swallow Gateway™. Metrics were compared to published normative values and generalized linear model tests explored modulatory effects.

RESULTS

21 participants (76% male; mean age 69.6 years, SD 7.1) with mild-moderate severity PD were studied. Two patients (9%) aspirated for single bolus thin liquid and paste trials and 15 patients (73%) scored > 3 EAT-10. Standardized PDQ-8 scores correlated with EAT-10 (p < 0.05). Abnormality in UES relaxation and distension was demonstrated by high UES integrated relaxation pressure and low UES maximum admittance (UES MaxAdm) values across varied bolus conditions. Participants demonstrated abnormally elevated pharyngeal contractility and increased post-swallow upper-esophageal sphincter (UES) contractility for thinner liquid trials. Alterations in volume and viscosity had significant effects on the bolus timing metric-distention to contraction latency. UES peak pressure measures were altered in relation to bolus viscosity.

CONCLUSION

This study identifies early pharyngoesophageal contractile changes in relation to bolus volume and viscosity in PD patients, associated with subtle deterioration of self-reported swallow scores. Manometric evaluation may offer insight into PD-related swallowing changes and help optimize diagnostics and treatment planning.

Parkinson's disease is associated with low striated esophagus contractility potentially contributing to the development of dysphagia

BACKGROUND

Parkinson's disease (PD) is the second most common neurodegenerative disorder, and more than 80% of PD patients will develop oropharyngeal dysphagia. Despite its striated histology, proximity to airway, and potential negative impact of its dysfunction on bolus transport and airway safety, the contractile function of the striated esophagus in PD patients has not been systematically studied.

METHODS

Using our repository of clinical manometry and the Milwaukee ManoBank, we analyzed high-resolution manometry (HRM) studies of 20 PD patients, mean age 69.1 (range 38-87 years); 30 non-PD patients with dysphagia, mean age 64.0 (44-86 years); and 32 healthy volunteers, mean age 65.3 (39-86 years). Patients with abnormal findings based on Chicago Classification 4.0 were identified. Repeat analysis was performed in 20% of the manometric tracings by a different investigator with inter-rater concordance between 0.91 and 0.99.

KEY RESULTS

The striated esophageal contractile integral in PD patients was significantly lower than that in non-PD dysphagic patients and healthy controls (p = 0.03 and <0.01, respectively). This significant difference persisted after excluding patients with concurrent Chicago Classification motility disorders (p = 0.02 and 0.01, respectively). In both analyses, the distal esophageal contractile integral did not show any significant difference between groups (p = 0.58 and 0.93, respectively).

CONCLUSIONS & INFERENCES

PD is associated with a significant decrease in striated esophagus contractility compared to non-PD and healthy controls. This finding may play a pathophysiologic role in development of dysphagia in this patient population.

Distal oesophageal spasm in a patient with multiple system atrophy: A case report

A 74-year-old man developed orthostatic syncope, a feeling of food stuck in his chest, and postprandial vomiting 3 years before presentation. Examination revealed severe orthostatic hypotension and cerebellar ataxia, and he was diagnosed with multiple system atrophy (MSA) with predominant cerebellar ataxia. Videofluoroscopic examination of swallowing showed lower oesophageal stricture and barium stagnation within the oesophagus. Oesophagogastroduodenoscopy revealed hypercontraction of the lower oesophagus, and high-resolution oesophageal manometry showed premature contractions of the lower oesophagus and decreased oesophageal peristalsis. The median integrated relaxation pressure in the lower oesophageal sphincter was normal, and achalasia was therefore excluded. Based on the Chicago classification version 4.0, his oesophageal dysmotility was classified as distal oesophageal spasm (DES). The stuck feeling in his chest and vomiting improved following endoscopic balloon dilation. This case suggests that DES can cause oesophageal food stagnation and postprandial vomiting in patients with MSA.

Investigating Parkinson's disease with dual high resolution pharyngeal manometry with impedance and videofluoroscopy

PURPOSE

To characterize pharyngeal function in people with Parkinson's Disease using both high resolution impedance manometry (HRIM) and videofluoroscopy (VFSS) and to explore correlations between VFSS and HRIM metrics.

METHODS

All participants received both VFSS and HRIM within 24 h-time window. A standard VFSS protocol (IDDSI 0: 1 mL, 3 mL, 20 mL, and 100 mL) was performed. A solid-state unidirectional catheter (36 pressure sensors) was used to acquire manometric data for triplicate swallows (IDDSI 0: 5 mL, 10 mL, 20 mL), quantitative swallow analysis was completed through Swallowtail™ and SwallowGateway™. Parameters were compared to published norms and statistical tests explored correlational associations (p < 0.05).

RESULTS

Twenty-one participants (76% male; mean age 70 years, SD7.16) with mild-moderate severity PD were recruited with 73% reporting Eating Assessment Tool (EAT-10) scores ≥3 indicating swallow impairment. Compared to normal metrics, one third of participants had abnormally elevated hypopharyngeal contractile integral (HPCI), hypopharyngeal peak pressure, upper esophageal sphincter (UES) integrated relaxation pressure (UES IRP), and reduced UES maximum admittance. Five participants showed compromised swallow safety (Penetration-Aspiration Scale score ≥6). One third of participants had abnormal VFSS values for pharyngoesophageal segment (PES) opening duration, maximum PES opening distance, and maximum hyoid displacement measures. Some HRIM metrics had a strong correlation with pharyngeal VFSS measures (r > 0.60, p < 0.05).

CONCLUSION

This study identifies early manometric signs of pharyngeal dysfunction in people with PD. The congruence of the VFSS and HRIM measures confirms the hypothesis of insidious early decline in swallow function in PD despite maintenance of airway safety (i.e., low aspiration rates).

Management of Gastrointestinal Symptoms in Parkinson's Disease: A Comprehensive Review of Clinical Presentation, Workup, and Treatment

Gastrointestinal symptoms in Parkinson's disease (PD) are among the most prevalent and debilitating of complications and present unique diagnostic and management challenges. Patients with PD commonly experience dysphagia, nausea, bloating, and constipation related to pathologic involvement of the enteric nervous system. In turn, gastrointestinal complications may impact motor fluctuations and the efficacy of levodopa therapy. This review will explore the common gastrointestinal manifestations of PD with an emphasis on clinical presentation, workup, and treatment strategies.

Management and Treatment for Dysphagia in Neurodegenerative Disorders

Patients with neurodegenerative disorders (NDDs) often experience functional dysphagia, which may involve dysfunction in a specific phase of swallowing or in the entire process. This review outlines the approach to dysphagia in the setting of NDDs. Distinguishing the etiology of dysphagia can be difficult, and it is important to always look out for signs pointing to NDD as the cause. Thorough diagnostic work-up is essential, and it includes a comprehensive history and physical examination, alongside swallowing function tests, such as fiberoptic endoscopic evaluation of swallowing, videofluoroscopic swallowing study, and high-resolution manometry. Management requires a multidisciplinary approach with a treatment plan tailored to each patient. This involves dietary guidance, swallowing rehabilitation, and surgery in cases in which improvement with rehabilitation is inadequate. Surgery may involve altering certain pharyngolaryngeal structures to facilitate swallowing and reduce the risk of aspiration (swallowing improvement surgery) or separating the airway and digestive tract while sacrificing laryngeal function, with the main goal of preventing aspiration (aspiration prevention surgery). Proper management stems from recognizing the impact of these disorders on swallowing and consistently finding ways to improve the quality of life of patients.

[Dysphagia in Parkinsonian Syndromes]

Dysphagia is a clinically relevant problem in Parkinson's disease as well as in atypical Parkinsonian syndromes, such as multiple system atrophy and diseases from the spectrum of 4‑repeat tauopathies, which affect most patients to a varying degree in the course of their disease. This results in relevant restrictions in daily life due to impaired intake of food, fluids, and medication with a subsequent reduction in quality of life. This article not only gives an overview of the pathophysiological causes of dysphagia in the various Parkinson syndromes, but also presents screening, diagnostic and treatment procedures that have been investigated for the different diseases.

Significance of clinical symptoms and red flags in early differential diagnosis of Parkinson's disease and atypical Parkinsonian syndromes

The clinical presentation of Parkinson's disease and atypical Parkinsonian syndromes is often heterogeneous. Additional diagnostic procedures including brain imaging and biomarker analyses can help to appreciate the various syndromes, but a precise clinical evaluation and differentiation is always necessary. To better assess the relevance of distinct clinical symptoms that arose within 1 year of disease manifestation and evaluate their indicative potential for an atypical Parkinsonian syndrome, we conducted a modified Delphi panel with seven movement disorder specialists. Five different topics with several clinical symptom items were discussed and consensus criteria were tested. This resulted in distinct symptom patterns for each atypical Parkinsonian syndrome showing the multitude of clinical involvement in each neurodegenerative disease. Strongly discriminating clinical signs were few and levels of indication were variable. A prospective validation of the assessments made is needed. This demonstrates that both clinical evaluation and elaborate additional diagnostic procedures are needed to achieve a high diagnostic standard.

Dysphagia in Parkinson Disease: Part I - Pathophysiology and Diagnostic Practices

Purpose of Review

Dysphagia affects the majority of individuals with Parkinson disease (PD) and is not typically diagnosed until later in disease progression. This review will cover the current understanding of PD pathophysiology, and provides an overview of dysphagia in PD including diagnostic practices, gaps in knowledge, and future directions.

Recent Findings

Many non-motor and other motor signs of PD appear in the prodrome prior to the manifestation of hall- mark signs and diagnosis. While dysphagia often presents already in the prodrome, it is not routinely addressed in standard neurology examinations.

Summary

Dysphagia in PD can result in compromised efficiency and safety of swallowing, which significantly contributes to malnutrition and dehydration, decrease quality of life, and increase mortality. The heterogeneous clinical presentation of PD complicates diagnostic procedures which often leads to delayed treatment. Research has advanced our knowledge of mechanisms underlying PD, but dysphagia is still largely understudied, especially in the prodromal stage.

[Parkinson's disease]

Parkinson's disease (PD) is an unparalleled example of a neurodegenerative disorder that can be effectively managed leading to sustained symptom control and quality of life. The cooperation of neurologists with general practitioners, gastroenterologists, and geriatricians is of increasing importance for an optimized management of PD. New diagnostic criteria for PD and for atypical Parkinsonism, which should be considered in the differential diagnostics, include non-motor symptoms and aim to diagnose these disorders as early as possible. Recent research has shown that there are highly complex and clinically relevant interactions with PD at all levels of the gastrointestinal tract, which have been increasingly better understood and have direct clinical relevance. Novel dopaminergic treatment approaches focus on circumvention of the impaired gastrointestinal tract of PD patients. The management of geriatric PD patients and PD dementia requires specific clinical knowledge. Worldwide, PD has emerged as a model disease for the development of network structures for the treatment of chronic neurological diseases.

Synucleinopathies

The α-synucleinopathies include pure autonomic failure, multiple system atrophy, dementia with Lewy bodies, and Parkinson disease. The past two decades have witnessed significant advances in the diagnostic strategies and symptomatic treatment of motor and nonmotor symptoms of the synucleinopathies. This chapter provides an in-depth review of the pathophysiology, pathology, genetic, epidemiology, and clinical and laboratory autonomic features that distinguish the different synucleinopathies with an emphasis on autonomic failure as a common feature. The treatment of the different synucleinopathies is discussed along with the proposal for multidisciplinary, individualized care models that optimally address the various symptoms. There is an urgent need for clinical scientific studies addressing patients at risk of developing synucleinopathies and the investigation of disease mechanisms, biomarkers, potential disease-modifying therapies, and further advancement of symptomatic treatments for motor and nonmotor symptoms.

Physiological Mechanisms and Associated Pathophysiology of Dysphagia in Older Adults

Dysphagia can be a common secondary sequela of neurological and neurodegenerative disorders in older adults. Early screening, identification, and management of dysphagia is essential to avoid serious complications, including malnutrition, dehydration, aspiration pneumonia; and promote quality of life. Although individuals of all ages may experience swallowing difficulties, dysphagia and its complications are more common in older adults. This literature review aims to provide an overview of the physiological mechanisms of normal swallowing in healthy individuals and age-related changes to swallowing function, the pathophysiology of dysphagia associated with three common neurological disorders affecting older adults (stroke, Parkinson's disease, and dementia), and implications for interdisciplinary clinical practice. Increased awareness of these issues may contribute to a more timely and efficient identification of older adults with dysphagia and to improve overall dysphagia management.

Assessment and treatment of neurogenic dysphagia in stroke and Parkinson's disease

PURPOSE OF REVIEW

Neurogenic dysphagia worsens quality of life and prognosis of patients with different neurological disorders. Management of neurogenic dysphagia can be challenging. This review provides a comprehensive overview of current evidence on screening, diagnosis, and treatment of neurogenic dysphagia in stroke and Parkinson's disease, suggesting clues for clinical practice.

RECENT FINDINGS

The pros and cons of diagnostic techniques are discussed in the light of updated evidence. Findings from recent meta-analyses of different treatment approaches, including traditional dysphagia therapy, peripheral and central neurostimulation techniques, and treatment with botulinum toxin, are critically discussed, emphasizing inconsistencies and controversial issues.

SUMMARY

Screening tests and clinical swallow examination should be routinely performed in neurological patients at risk for dysphagia. In patients testing positive for dysphagia, first-line instrumental investigations, represented by fiberoptic endoscopic evaluation of swallowing or videofluoroscopic swallow study, should be performed to confirm the presence of dysphagia, to assess its severity, and to inform the treatment. Second-line and third-line instrumental methods can be used in selected patients to clarify specific pathophysiological aspects of oropharyngeal dysphagia. Treatment strategies should be personalized, and combination of traditional dysphagia therapy with innovative treatment approaches may increase the chance of restoring effective and safe swallowing.

Management of dysphagia and gastroparesis in Parkinson's disease in real-world clinical practice - Balancing pharmacological and non-pharmacological approaches

Gastrointestinal (GI) issues are commonly experienced by patients with Parkinson's disease (PD). Those that affect the lower GI tract, such as constipation, are the most frequently reported GI problems among patients with PD. Upper GI issues, such as swallowing dysfunction (dysphagia) and delayed gastric emptying (gastroparesis), are also common in PD but are less well recognized by both patients and clinicians and, therefore, often overlooked. These GI issues may also be perceived by the healthcare team as less of a priority than management of PD motor symptoms. However, if left untreated, both dysphagia and gastroparesis can have a significant impact on the quality of life of patients with PD and on the effectiveness on oral PD medications, with negative consequences for motor control. Holistic management of PD should therefore include timely and effective management of upper GI issues by utilizing both non-pharmacological and pharmacological approaches. This dual approach is key as many pharmacological strategies have limited efficacy in this setting, so non-pharmacological approaches are often the best option. Although a multidisciplinary approach to the management of GI issues in PD is ideal, resource constraints may mean this is not always feasible. In 'real-world' practice, neurologists and PD care teams often need to make initial assessments and treatment or referral recommendations for their patients with PD who are experiencing these problems. To provide guidance in these cases, this article reviews the published evidence for diagnostic and therapeutic management of dysphagia and gastroparesis, including recommendations for timely and appropriate referral to GI specialists when needed and guidance on the development of an effective management plan.

Establishing gene regulatory networks from Parkinson's disease risk loci

The latest meta-analysis of genome-wide association studies identified 90 independent variants across 78 genomic regions associated with Parkinson's disease, yet the mechanisms by which these variants influence the development of the disease remains largely elusive. To establish the functional gene regulatory networks associated with Parkinson's disease risk variants, we utilized an approach combining spatial (chromosomal conformation capture) and functional (expression quantitative trait loci) data. We identified 518 genes subject to regulation by 76 Parkinson's variants across 49 tissues, whicih encompass 36 peripheral and 13 CNS tissues. Notably, one-third of these genes were regulated via trans-acting mechanisms (distal; risk locus-gene separated by >1 Mb, or on different chromosomes). Of particular interest is the identification of a novel trans-expression quantitative trait loci-gene connection between rs10847864 and SYNJ1 in the adult brain cortex, highlighting a convergence between familial studies and Parkinson's disease genome-wide association studies loci for SYNJ1 (PARK20) for the first time. Furthermore, we identified 16 neurodevelopment-specific expression quantitative trait loci-gene regulatory connections within the foetal cortex, consistent with hypotheses suggesting a neurodevelopmental involvement in the pathogenesis of Parkinson's disease. Through utilizing Louvain clustering we extracted nine significant and highly intraconnected clusters within the entire gene regulatory network. The nine clusters are enriched for specific biological processes and pathways, some of which have not previously been associated with Parkinson's disease. Together, our results not only contribute to an overall understanding of the mechanisms and impact of specific combinations of Parkinson's disease variants, but also highlight the potential impact gene regulatory networks may have when elucidating aetiological subtypes of Parkinson's disease.

Severity of dysphagia is associated with hospitalizations and mortality in patients with Parkinson's disease

BACKGROUND

Aspiration pneumonia is the commonest cause of hospitalizations and death in patients with Parkinson's disease (PD). Among these patients, the relationships between severity of dysphagia, hospitalizations for related complications, and death are not robustly defined. Our aim was to characterize the relationship between PD-related oropharyngeal dysfunction and clinically relevant outcomes.

METHODS

Retrospective cohort study of 312 patients with PD at a tertiary center who underwent videofluoroscopic swallow studies conducted by expert therapists between 2010 and 2015. Level of swallowing function was represented using the 7-point Functional Oral Intake Scale (FOIS) (7 = normal function). Significance and relative risk calculations utilized Poisson regression. Time to composite outcome of first hospitalization or death was summarized using Kaplan-Meier curve with log-rank test.

KEY RESULTS

One hundred thirty eight patients had a recorded FOIS score. The prevalence of oropharyngeal dysfunction was 76.1%. The median duration of follow-up was 26.8 months. In multivariate analyses, patients with FOIS 5 (RR = 2.01 [95% CI: 1.22, 3.32]), FOIS 3 (RR = 2.78 [95% CI: 1.75, 4.40]), and FOIS 1 (RR = 2.50 [95% CI: 1.49, 4.20]) were significantly associated with increased risk of hospitalization or death compared to FOIS 7 after co-variate adjustments. GERD was also associated with a significant increased risk of hospitalization or death (RR = 1.28 [95% CI: 1.01, 1.64]). Time to first hospitalization or death was shorter in patients with lower FOIS scores (p < 0.00005).

CONCLUSIONS AND INFERENCES

Severity of oropharyngeal dysphagia, as measured by the FOIS, is associated with poorer survival and shorter time to hospitalization for dysphagia-related complications, pneumonia, or death in PD.

Evaluation of oropharyngeal deglutitive pressure dynamics in patients with Parkinson's disease

In Parkinson's disease (PD), oropharyngeal dysphagia is common and clinically relevant. The neurophysiology of dysphagia in PD is complex and incompletely understood. The aim of the study was to determine the changes in oropharyngeal deglutitive pressure dynamics in PD and to correlate these with clinical characteristics including dysphagia and PD severity. In prospective consecutive series of 64 patients with PD [mean age: 66.9 ± 8.3 (SD)], we evaluated dysphagia severity clinically as well as with Sydney Swallow Questionnaire (SSQ) and Swallow Quality-of-Life Questionnaire (SWAL-QOL). PD severity was assessed with Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS). We used high-resolution pharyngeal impedance manometry (HRPIM) to objectively evaluate swallow function and compared data from 23 age-matched healthy controls [mean age 62.3 ± 9.1 (SD)]. Metrics assessed were upper esophageal sphincter (UES), integrated relaxation pressure (IRP), relaxation time (RT), maximum opening (MaxAdm), and pharyngeal intrabolus pressure (IBP) and pharyngeal contractility (PhCI). Mean MDS-UPDRS score was positively associated with dysphagia severity on SSQ and SWAL-QOL. HRPIM in PD compared with controls showed impaired UES relaxation parameters, with shorter RT, and elevated IRP and IBP. MaxAdm was not affected. The overall pharyngeal contractility was significantly higher in PD. Only the IBP and IRP were associated with PD severity and only IBP was significantly associated with dysphagia severity. UES dysfunction leading to increased flow resistance is common in patients with PD and correlates with dysphagia severity. Increased flow resistance may suggest impaired UES relaxation and/or impaired neuromodulation to bolus volume.NEW & NOTEWORTHY In Parkinson's disease, objective assessment of swallow function with high-resolution impedance manometry identifies upper esophageal sphincter dysfunction leading to increased flow resistance.

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.

A multinational consensus on dysphagia in Parkinson's disease: screening, diagnosis and prognostic value

Background

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by a combination of motor and non-motor dysfunction. Dysphagia is a common symptom in PD, though it is still too frequently underdiagnosed. Consensus is lacking on screening, diagnosis, and prognosis of dysphagia in PD.

Objective

To systematically review the literature and to define consensus statements on the screening and the diagnosis of dysphagia in PD, as well as on the impact of dysphagia on the prognosis and quality of life (QoL) of PD patients.

Methods

A multinational group of experts in the field of neurogenic dysphagia and/or PD conducted a systematic revision of the literature published since January 1990 to February 2021 and reported the results according to PRISMA guidelines. The output of the research was then analyzed and discussed in a consensus conference convened in Pavia, Italy, where the consensus statements were drafted. The final version of statements was subsequently achieved by e-mail consensus.

Results

Eighty-five papers were used to inform the Panel’s statements even though most of them were of Class IV quality. The statements tackled four main areas: (1) screening of dysphagia: timing and tools; (2) diagnosis of dysphagia: clinical and instrumental detection, severity assessment; (3) dysphagia and QoL: impact and assessment; (4) prognostic value of dysphagia; impact on the outcome and role of associated conditions.

Conclusions

The statements elaborated by the Consensus Panel provide a framework to guide the neurologist in the timely detection and accurate diagnosis of dysphagia in PD.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-021-10739-8.

Gastrointestinal dysfunction in movement disorders

PURPOSE OF REVIEW

This article provides an overview of the clinical presentation, investigations, and treatment options for gastrointestinal tract (GIT) dysfunction in patients with Parkinson's disease (PD) and other movement disorders.

RECENT FINDINGS

GIT dysfunction commonly appears as constipation and fecal incontinence (mostly overflow, accompanied with sphincter failure in multiple system atrophy [MSA]). Bowel dysfunction (underactive) occurs irrespectively from the site of the neurologic lesion, which is in contrast to site-dependent bladder dysfunction (brain, overactive; periphery, underactive). GI emergencies may arise, including intestinal pseudo-obstruction, intussusception, volvulus, and stercoral ulcer (ulcer of the colon due to pressure and irritation resulting from severe, prolonged constipation). Bowel function tests in neurologic patients often show a combination of slow transit and anorectal dysfunction. Management for slow transit constipation includes bulking agents, softening agents, yogurt/probiotics, and prokinetic agents. Suppositories, botulinum toxin injections, and transanal irrigation are options for managing anorectal constipation.

CONCLUSIONS

Function of the bowel is commonly affected in PD and other movement disorders. Neurologists play an important role in assessing bowel symptoms in their patients and planning treatment strategies, often in collaboration with specialist teams.

Gastrointestinal Dysfunction in Parkinson's Disease

Parkinson’s disease (PD) is the second most common neurodegenerative disease. Patients show deposits of pathological, aggregated α-synuclein not only in the brain but throughout almost the entire length of the digestive tract. This gives rise to non-motor symptoms particularly within the gastrointestinal tract and patients experience a wide range of frequent and burdensome symptoms such as dysphagia, bloating, and constipation. Recent evidence suggests that progressive accumulation of gastrointestinal pathology is underway several years before a clinical diagnosis of PD. Notably, constipation has been shown to increase the risk of developing PD and in contrast, truncal vagotomy seems to decrease the risk of PD. Animal models have demonstrated gut-to-brain spreading of pathological α-synuclein and it is currently being intensely studied whether PD begins in the gut of some patients. Gastrointestinal symptoms in PD have been investigated by the use of several different questionnaires. However, there is limited correspondence between subjective gastrointestinal symptoms and objective dysfunction along the gastrointestinal tract, and often the magnitude of dysfunction is underestimated by the use of questionnaires. Therefore, objective measures are important tools to clarify the degree of dysfunction in future studies of PD. Here, we summarize the types and prevalence of subjective gastrointestinal symptoms and objective dysfunction in PD. The potential importance of the gastrointestinal tract in the etiopathogenesis of PD is briefly discussed.

Evaluation of the pharynx and upper esophageal sphincter motility using high-resolution pharyngeal manometry for Parkinson's disease

Parkinson's disease (PD) is associated with a high incidence of dysphagia. Aspiration pneumonia due to dysphagia is a major cause of death in patients with PD, and therefore accurately evaluating dysphagia should help improve prognosis. It has been reported that the severity of dysphagia does not always correlate with the Hoehn and Yahr (H&Y) stage for classifying PD severity. However, no reports have quantitatively evaluated the relationship between severity of dysphagia and H&Y stage. High-resolution pharyngeal manometry (HRPM) is a quantitative method that can be used to measure swallowing pressure from the velopharynx to the entry of the upper esophageal sphincter (UES). We used HRPM to measure swallowing pressure in 51 patients with PD. As PD progresses, atrophy and degeneration of the pharyngeal muscles become more pronounced, which contributes to dysphagia. However, thus far there is no quantitative clinical evidence for this pathological change. To evaluate the relationship between severity of underlying PD and dysphagia, patients were categorized by H&Y stage, as follows: stage II in four patients, stage III in 23, stage IV in 14, and stage V in 10. In patients with H&Y stages II, III, IV, and V, the respective velopharyngeal pressures were 179.8 ± 32.5, 157.6 ± 62.2, 172.2 ± 48.9, and 107.4 ± 44.0 mmHg, the mesopharyngeal pressures were 126.8 ± 53.2, 121.6.1 ± 50.4, 142.1 ± 57.8, and 61.4 ± 19.6 mmHg, the residual UES pressure were -8.0 ± 10.8, 10.3 ± 16.1, 16.5 ± 37.9, and 11.2 ± 16.2 mmHg, and the resting UES pressure were 49.5 ± 30.0, 15.8 ± 25.7, 1.85 ± 14.1, and -1.2 ± 12.2 mmHg. Patients with severe PD demonstrated significantly decreased velopharyngeal and oropharyngeal pressures, along with incomplete UES opening and contraction. HRPM can detect subtle abnormalities by quantifying swallowing pressure in patients with PD. Evaluating swallowing pressure with HRPM provides insights into neuromuscular dysfunction that causes abnormal pressure generation during pharyngeal swallowing in patients with PD.

Autonomic Dysfunction in the Synucleinopathies

Autonomic dysfunction is a characteristic feature in the synucleinopathies. Differences in cellular deposition and neuronal populations affected by α-synuclein aggregation influence the manifestations and severity of autonomic failure in the different synucleinopathy disorders. The Lewy body disorders (Parkinson's disease, dementia with Lewy bodies, and pure autonomic failure) have predominantly peripheral involvement, whereas multiple system atrophy chiefly manifests as central autonomic failure. Clinical and laboratory features may be useful in distinguishing the different synucleinopathies based on the pattern and severity of autonomic failure. Treatment recommendations are aimed at the underlying pathophysiology and utilize non-pharmacologic and pharmacologic approaches. This review will focus on pathophysiology, clinical manifestations, and management recommendations for autonomic failure including neurogenic orthostatic hypotension, thermoregulatory dysfunction, genitourinary dysfunction, and gastrointestinal dysfunction in the synucleinopathies.

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.

Excessive daytime sleepiness is associated to the development of swallowing impairment in a cohort of early stage drug naïve Parkinson's disease patients

OBJECTIVE

The aim of the present study was to investigate the potential predictors of subjectively reported swallowing impairment in a cohort of early-stage and drug naïve Parkinson's disease patients.

METHODS

A retrospective analysis of the Parkinson Progression Markers Initiative (PPMI) data was conducted. PD patients with score ≥ 1 on MDS-UPDRS "item 2.3" and on SCOPA-AUT "question 1" were classified as "dysphagic" and were compared with "non-dysphagic" patients at baseline. After excluding baseline dysphagic subjects, we assessed the predictors of the development of dysphagia in the third year of follow-up.

RESULTS

The baseline prevalence of dysphagia in PD was 10.4%, growing as high as 19.1% within year 3. Compared to PD subjects not complaining swallowing difficulties, dysphagic patients had significantly higher scores on REM sleep behavior questionnaire, Epworth sleepiness scale (ESS), geriatric depression scale and MDS-UPDRS I (p < .01), significantly lower caudate [¹²³I]FP-CIT uptake parameters and BMI, and mild cognitive changes at symbol digit modalities (p < .01). In the longitudinal analysis of non-dysphagic patients, 14.6% developed dysphagic symptoms at year 3. Excessive daytime sleepiness estimated through ESS was strongly related to the development of swallowing impairment at year 3 in the univariate (odds ratio 3.2, p < .001) and multivariate regression model (odds ratio 2.5, p = .01).

CONCLUSIONS

Early-stage PD patients often report swallowing difficulties. We found a close relationship between excessive daytime sleepiness and the development of swallowing impairment over three years of follow-up of de novo patients.

Substance P Saliva Reduction Predicts Pharyngeal Dysphagia in Parkinson's Disease

Introduction: Although patients with Parkinson's disease (PD) often suffer from oropharyngeal dysphagia, knowledge about the underlying pathophysiological mechanisms is limited. Substance P (SP) is a localization-independent neurotransmitter of the entire nervous system. Reduced levels of SP were found in saliva of patients with impaired cough reflex and in advanced stages of PD. The aim of the study was to investigate SP in PD patients in order to gain further insights into the underlying pathophysiology of PD-related dysphagia and to evaluate the potential of SP as a biomarker for early dysphagia.

Methods: Flexible endoscopic evaluation of swallowing (FEES) was used to objectively assess pharyngeal swallowing function. From a cohort of 105 consecutive PD patients 20 subjects were recruited: in 10 of them pharyngeal dysphagia was excluded by FEES, the other 10 subjects showed signs of early pharyngeal dysphagia defined as hypopharyngeal sensory deficit with mild to moderate vallecular residues after swallowing solid consistencies. Analysis of the Substance P level in saliva of the 20 included PD patients was performed in the clinical on state condition by ELISA-type immunoassay. Significant differences were calculated by using the Mann-Whitney test.

Results: Twenty PD patients with a mean age of 69.5 ± 12.5 years (8 female) were included in the study. No significant differences were found regarding gender, age, UPDRS III, Hoehn and Yahr stage, disease duration, and Levodopa equivalent dose between the non-dysphagic and dysphagic subjects. Dysphagia was mainly characterized by unrecognized residues in the valleculae without any aspiration risk for all of the tested consistencies in FEES and was thereby scored as mild in all cases. Saliva SP concentrations were significantly lower in PD patients with pharyngeal dysphagia compared to those with a normal pharyngeal swallowing function (9,644 vs. 17,591 pg/mL; p = 0.001).

Conclusion: Reduced saliva SP concentrations may predict early pharyngeal swallowing dysfunction in PD patients. This finding supports the hypothesis that an impaired SP mediated neurotransmission has a significant impact for the development of dysphagia in PD patients. Larger studies are needed to confirm SP as a clinical useful biomarker for early detection of PD-related dysphagia.

Prevalence and Associated Impacts of Cervical Esophageal Clearance Issues Post Chemoradiotherapy for Nasopharyngeal Carcinoma (NPC)

At present, the nature and extent of upper esophageal stage clearance issues following nonsurgical management of nasopharyngeal cancer (NPC) is not well elucidated. The aim of this study was to conduct an initial retrospective study of the prevalence and severity of upper esophageal clearance impairments in a cohort of patients post-NPC management. A secondary aim was to explore any observed relationship between severity of impairment with both (a) aspiration and (b) temporal oropharyngeal swallowing measures. A cohort of 134 NPC patients who received curative intent (chemo)radiotherapy (C/RT) and completed a videofluoroscopic swallowing study (VFSS) between 2012 and 2015 were reviewed. An Esophageal Clearance parameter, based on the scale used in MBSImP was used to classify the presence and severity of esophageal impairment on thin liquid and semisolids. Data on oral and pharyngeal temporal measures, pharyngeal constriction, and penetration/aspiration were also collected. The prevalence of cervical esophageal clearance impairment was high with ratings > 0 observed among 83% and 97% of patients on thin liquid and semisolids, respectively. With the increasing impairment, significantly (p < 0.05) increased oral transit times were observed for liquid swallows, and increased pharyngeal transit times for semisolids. Significantly higher proportions of patients presented with penetration/aspiration in the group with more severe esophageal clearance impairment. Results confirm that cervical esophageal clearance impairment is highly prevalent post-C/RT treatment for NPC. Causality cannot be determined from this study; however, this initial evidence supports that esophageal impairment may coexist in patients post NPC, presenting with more severe oral/pharyngeal deficits, and the impact of this on swallow function needs to be considered. Further systematic research is required.

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.

Imaging the Autonomic Nervous System in Parkinson's Disease

PURPOSE OF REVIEW

Patients with Parkinson's disease (PD) often display gastrointestinal and genitourinary autonomic symptoms years or even decades prior to diagnosis. These symptoms are thought to be caused in part by pathological α-synuclein inclusions in the peripheral autonomic and enteric nervous systems. It has been proposed that the initial α-synuclein aggregation may in some PD patients originate in peripheral nerve terminals and then spread centripetally to the spinal cord and brainstem. In vivo imaging methods can directly quantify the degeneration of the autonomic nervous system as well as the functional consequences such as perturbed motility. Here, we review the methodological principles of these imaging techniques and the major findings in patients with PD and atypical parkinsonism.

RECENT FINDINGS

Loss of sympathetic and parasympathetic nerve terminals in PD can be visualized using radiotracer imaging, including ¹²³I-MIBG scintigraphy, and ¹⁸F-dopamine and ¹¹C-donepezil PET. Recently, ultrasonographical studies disclosed reduced diameter of the vagal nerves in PD patients. Radiological and radioisotope techniques have demonstrated dysmotility and prolonged transit time throughout all subdivisions of the gastrointestinal tract in PD. The prevalence of objective dysfunction as measured with these imaging methods is often considerably higher compared to the prevalence of subjective symptoms experienced by the patients. Degeneration of the autonomic nervous system may play a key role in the pathogenesis of PD. In vivo imaging techniques provide powerful and noninvasive tools to quantify the degree and extent of this degeneration and its functional consequences.

Subtle Esophageal Motility Alterations in Parkinsonian Syndromes: Synucleinopathies vs. Tauopathies

BACKGROUND

Esophageal dysfunction is a frequent phenomenon in Parkinson's disease during all disease stages, but data about esophageal involvement in atypical parkinsonian syndromes as well as possible differences between alpha-synucleinopathies and tauopathies, including causative links to the origin of the dysfunction, are lacking so far.

OBJECTIVE

To describe esophageal alternation patterns in different parkinsonian syndromes and to look for differences supporting the hypothesis of alpha-synuclein aggregation being linked to gastrointestinal impairment in parkinsonian syndromes.

METHODS

We performed an analysis and comparison of esophageal high-resolution manometry examination parameters in n = 10 patients with Parkinson's disease, n = 10 patients with multiple system atrophy (both alpha-synucleinopathies), n = 10 patients with progressive supranuclear palsy (tauopathy), and n = 10 age-matched controls. Additionally, pharyngeal dysphagia was evaluated by an endoscopic examination of swallowing in all three patient groups.

RESULTS

Statistically significant lower values for esophageal peristalsis and distal contractile integral were found for both groups of alpha-synucleinopathies (Parkinson's disease and multiple system atrophy) in comparison to the patients with tauopathy (progressive supranuclear palsy group), as well as the age-matched controls, where pathological pharyngeal findings were similar in all patient groups.

CONCLUSIONS

Subtle esophageal motility alterations in parkinsonian syndromes seem to be limited to alpha-synucleinopathies, but are not measurable in tauopathies, indicating a causative connection between pathological alpha-synuclein aggregation in gastrointestinal tissues and esophageal involvement.

Treatment of autonomic dysfunction in Parkinson disease and other synucleinopathies

Dysfunction of the autonomic nervous system afflicts most patients with Parkinson disease and other synucleinopathies such as dementia with Lewy bodies, multiple system atrophy, and pure autonomic failure, reducing quality of life and increasing mortality. For example, gastrointestinal dysfunction can lead to impaired drug pharmacodynamics causing a worsening in motor symptoms, and neurogenic orthostatic hypotension can cause syncope, falls, and fractures. When recognized, autonomic problems can be treated, sometimes successfully. Discontinuation of potentially causative/aggravating drugs, patient education, and nonpharmacological approaches are useful and should be tried first. Pathophysiology-based pharmacological treatments that have shown efficacy in controlled trials of patients with synucleinopathies have been approved in many countries and are key to an effective management. Here, we review the treatment of autonomic dysfunction in patients with Parkinson disease and other synucleinopathies, summarize the nonpharmacological and current pharmacological therapeutic strategies including recently approved drugs, and provide practical advice and management algorithms for clinicians, with focus on neurogenic orthostatic hypotension, supine hypertension, dysphagia, sialorrhea, gastroparesis, constipation, neurogenic overactive bladder, underactive bladder, and sexual dysfunction. © 2018 International Parkinson and Movement Disorder Society.

Objective Measurement and Monitoring of Nonmotor Symptoms in Parkinson's Disease

The comprehensive evaluation of nonmotor symptoms (NMS) in Parkinson's disease (PD) starts with the awareness of physicians, patients, and caregivers on their nature, clinical presentation, and effect on patient's daily activities and quality of life. This awareness can be better achieved if the symptoms can be visualized, measured, and monitored. As NMS are largely subjective in nature, a majority of them cannot be visualized (unlike tremor, which is easily seen), making their identification and quantification difficult. While symptoms are nonmotor, it does not mean that they are not measurable, as many NMS are integral to motor symptoms of Parkinson's, yet often neglected. In this review, we attempt to provide the most up-to-date and comprehensive literature review on the objective measurement and monitoring of NMS in PD. The aim is to make it clinically relevant by approaching NMS by domains as identified in the NMS Questionnaire. A section on the assessment of nonmotor fluctuations is also included, providing prospects for future objective monitoring. With the advances of technology, it is likely that many NMS will have objective outcomes, thus making these symptoms easily measurable and hopefully lead to future clinical trials that incorporate nonmotor outcomes. Nevertheless, it still requires a physician's judgment to determine which method, scales, objective measures, or monitoring devices or a combination of these is most appropriate to the individual patient in order to answer a particular clinical question.

Swallowing in Parkinson's disease: clinical issues and management

Changes to swallowing affect most people with Parkinson's disease (PD). Changes may not initially exercise a decisive impact, but can later pose significant threats to nutritional, hydration and respiratory health and psychosocial quality of life. This review, from a largely clinical viewpoint, outlines the nature of changes in PD and considers the issue of how many people are affected and in what ways. It outlines main approaches to assessment and management, with an emphasis on aspects relevant to PD. Dysphagia contributes to drooling in PD. The review therefore also touches on the nature and management of this condition that has its own set of health and psychosocial quality-of-life issues.

Imaging Parkinson's disease below the neck

Parkinson's disease is a systemic disorder with widespread and early α-synuclein pathology in the autonomic and enteric nervous systems, which is present throughout the gastrointestinal canal prior to diagnosis. Gastrointestinal and genitourinary autonomic symptoms often predate clinical diagnosis by several years. It has been hypothesized that progressive α-synuclein aggregation is initiated in hyperbranched, non-myelinated neuron terminals, and may subsequently spread via retrograde axonal transport. This would explain why autonomic nerves are so prone to formation of α-synuclein pathology. However, the hypothesis remains unproven and in vivo imaging methods of peripheral organs may be essential to study this important research field. The loss of sympathetic and parasympathetic nerve terminal function in Parkinson's disease has been demonstrated using radiotracers such as 123I-meta-iodobenzylguanidin, 18F-dopamine, and 11C-donepezil. Other radiotracer and radiological imaging methods have shown highly prevalent dysfunction of pharyngeal and esophageal motility, gastric emptying, colonic transit time, and anorectal function. Here, we summarize the methodology and main findings of radio-isotope and radiological modalities for imaging peripheral pathology in Parkinson's disease.