Acute Deterioration of Bulbar Function After Botulinum Toxin Treatment for Sialorrhoea in Amyotrophic Lateral Sclerosis

Treatment for sialorrhea (excessive saliva) in people with motor neuron disease/amyotrophic lateral sclerosis

BACKGROUND

Motor neuron disease (MND), also known as amyotrophic lateral sclerosis (ALS), is a progressive neurodegenerative condition that may cause dysphagia, as well as limb weakness, dysarthria, emotional lability, and respiratory failure. Since normal salivary production is 0.5 L to 1.5 L daily, loss of salivary clearance due to dysphagia leads to salivary pooling and sialorrhea, often resulting in distress and inconvenience to people with MND. This is an update of a review first published in 2011.

OBJECTIVES

To assess the effects of treatments for sialorrhea in MND, including medications, radiotherapy and surgery.

SEARCH METHODS

On 27 August 2021, we searched the Cochrane Neuromuscular Specialised Register, CENTRAL, MEDLINE, Embase, AMED, CINAHL, ClinicalTrials.gov and the WHO ICTRP. We checked the bibliographies of the identified randomized trials and contacted trial authors as needed. We contacted known experts in the field to identify further published and unpublished papers.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) and quasi-RCTs, including cross-over trials, on any intervention for sialorrhea and related symptoms, compared with each other, placebo or no intervention, in people with ALS/MND.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We identified four RCTs involving 110 participants with MND who were described as having intractable sialorrhea or bulbar dysfunction. A well-designed study of botulinum toxin B compared to placebo injected into the parotid and submandibular glands of 20 participants showed that botulinum toxin B may produce participant-reported improvement in sialorrhea, but the confidence interval (CI) was also consistent with no effect. Six of nine participants in the botulinum group and two of nine participants in the placebo group reported improvement (risk ratio (RR) 3.00, 95% CI 0.81 to 11.08; 1 RCT; 18 participants; low-certainty evidence). An objective measure indicated that botulinum toxin B probably reduced saliva production (in mL/5 min) at eight weeks compared to placebo (MD -0.50, 95% CI -1.07 to 0.07; 18 participants, moderate-certainty evidence). Botulinum toxin B may have little to no effect on quality of life, measured on the Schedule for Evaluation of Individual Quality of Life direct weighting scale (SEIQoL-DW; 0-100, higher values indicate better quality of life) (MD -2.50, 95% CI -17.34 to 12.34; 1 RCT; 17 participants; low-certainty evidence). The rate of adverse events may be similar with botulinum toxin B and placebo (20 participants; low-certainty evidence). Trialists did not consider any serious events to be related to treatment. A randomized pilot study of botulinum toxin A or radiotherapy in 20 participants, which was at high risk of bias, provided very low-certainty evidence on the primary outcome of the Drool Rating Scale (DRS; range 8 to 39 points, higher scores indicate worse drooling) at 12 weeks (effect size -4.8, 95% CI -10.59 to 0.92; P = 0.09; 1 RCT; 16 participants). Quality of life was not measured. Evidence for adverse events, measured immediately after treatment (RR 7.00, 95% CI 1.04 to 46.95; 20 participants), and after four weeks (when two people in each group had viscous saliva) was also very uncertain. A phase 2, randomized, placebo-controlled cross-over study of 20 mg dextromethorphan hydrobromide and 10 mg quinidine sulfate (DMQ) found that DMQ may produce a participant-reported improvement in sialorrhea, indicated by a slight improvement (decrease) in mean scores for the primary outcome, the Center for Neurologic Study Bulbar Function Scale (CNS-BFS). Mean total CNS-BFS (range 21 (no symptoms) to 112 (maximum symptoms)) was 53.45 (standard error (SE) 1.07) for the DMQ treatment period and 59.31 (SE 1.10) for the placebo period (mean difference) MD -5.85, 95% CI -8.77 to -2.93) with a slight decrease in the CNS-BFS sialorrhea subscale score (range 7 (no symptoms) to 35 (maximum symptoms)) compared to placebo (MD -1.52, 95% CI -2.52 to -0.52) (1 RCT; 60 participants; moderate-certainty evidence). The trial did not report an objective measure of saliva production or measure quality of life. The study was at an unclear risk of bias. Adverse events were similar to other trials of DMQ, and may occur at a similar rate as placebo (moderate-certainty evidence, 60 participants), with the most common side effects being constipation, diarrhea, nausea, and dizziness. Nausea and diarrhea on DMQ treatment resulted in one withdrawal. A randomized, double-blind, placebo-controlled cross-over study of scopolamine (hyoscine), administered using a skin patch, involved 10 randomized participants, of whom eight provided efficacy data. The participants were unrepresentative of clinic cohorts under routine clinical care as they had feeding tubes and tracheostomy ventilation, and the study was at high risk of bias. The trial provided very low-certainty evidence on sialorrhea in the short term (7 days' treatment, measured on the Amyotrophic Lateral Scelerosis Functional Rating Scale-Revised (ALSFRS-R) saliva item (P = 0.572)), and the amount of saliva production in the short term, as indicated by the weight of a cotton roll (P = 0.674), or daily oral suction volume (P = 0.69). Quality of life was not measured. Adverse events evidence was also very uncertain. One person treated with scopolamine had a dry mouth and one died of aspiration pneumonia considered unrelated to treatment.

AUTHORS' CONCLUSIONS

There is some low-certainty or moderate-certainty evidence for the use of botulinum toxin B injections to salivary glands and moderate-certainty evidence for the use of oral dextromethorphan with quinidine (DMQ) for the treatment of sialorrhea in MND. Evidence on radiotherapy versus botulinum toxin A injections, and scopolamine patches is too uncertain for any conclusions to be drawn. Further research is required on treatments for sialorrhea. Data are needed on the problem of sialorrhea in MND and its measurement, both by participant self-report measures and objective tests. These will allow the development of better RCTs.

The Role of Radiation Therapy and Botulinum Toxin Injections in the Management of Sialorrhea in Patients With Amyotrophic Lateral Sclerosis: A Systematic Review

OBJECTIVES

Half of patients with amyotrophic lateral sclerosis experience sialorrhea due to facial weakness. Although anticholinergic medications are first-line therapy, they often lead to unacceptable side effects. Radiation therapy and botulinum toxin may be considered when medical management fails. In this systematic review, we investigated the effectiveness of these interventions.

METHODS

Eligible studies were retrieved from PubMed and Scopus databases up to March 2017 along with hand-searching of references from primary articles.

RESULTS

Fourteen studies (N = 138) examined the benefits of botulinum toxin. Studies varied in salivary glands treated, dosages used, and the use of botulinum toxin subtype A or B. A majority of studies showed benefit after treatment. Although most studies reported only mild adverse effects, 2 case studies revealed severe complications including recurrent TMJ dislocations and rapid deterioration in bulbar function. Ten studies (N = 171) examined the benefits of radiation. Most studies reported improvement with only mild adverse events reported.

CONCLUSIONS

Both radiation and botulinum toxin are effective treatments for sialorrhea in patients with amyotrophic lateral sclerosis and should be considered when medical management fails. Radiation may offer longer duration of symptom improvement with fewer complications.

Sialorrhea in patients with ALS: current treatment options

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder of the motor neuron, which selectively affects it both at central (first motor-neuron) and peripheral level (second motor-neuron). The disease shows up at a mean age of 56 years and the most affected are males. Although ALS may start as a bulbar or spinal disease, with the progression of the disease typically both become evident. Pharmacological approved treatments for ALS are still limited and include riluzole and edaravone which improve survival over time. Despite this, ALS leads to progressive muscle involvement and requires a complex multidisciplinary approach to manage increasing disability which goes beyond motor neurons. Sialorrhea is, amongst others, one of the most disabling symptoms in ALS. The complexity in managing saliva is due to a muscular spasticity and to a scarce palatino-lingual muscles control, rather than to an overproduction of saliva. These features could increase the risk of aspiration pneumonia and limit the use of noninvasive mechanical ventilation. We reviewed the treatment for sialorrhea in ALS patients that are available at this time, emphasizing pros and cons for each approach. Our purpose is to create a practical tool for the diagnosis, in order to facilitate the quantification and management of sialorrhea in everyday practice.

Botulinum toxin-A injections vs radiotherapy for drooling in ALS

OBJECTIVES

Botulinum neurotoxin (BoNT) injections in the salivary glands and radiotherapy (RT) on these glands are commonly used to alleviate severe drooling in patients with amyotrophic lateral sclerosis (ALS). This study compares BoNT type A with RT based on patient-rated evaluations.

MATERIALS & METHODS

A prospective randomized controlled pilot study to compare RT (n = 10; on the parotid and the posterior part of the submandibular glands) with BoNT-A treatment (n = 10; in the parotid glands only, because of the risk of increasing oropharyngeal weakness) in patients with ALS. The primary outcome was the drooling status (burden of drooling), and our secondary interests were the degree of salivation, global change of drooling after treatment, and level of satisfaction with the treatment and negative experiences.

RESULTS

There were no statistically significant between-treatment differences for the drooling status after treatment. Only at twelve weeks more saliva reduction was achieved by RT (P = 0.02). Patients treated with RT also described more transient negative experiences (like pain in mandible) directly after treatment. Subgroup analysis showed that patients with very severe dysphagia (no oral intake) were less satisfied and experienced a lower global change of drooling after treatment.

CONCLUSIONS

This pilot study showed no significant difference in the burden of drooling between the treatments. However, with RT more saliva reduction was achieved, including negative experiences directly after treatment, but without the risk of decreasing oropharyngeal function. In addition, patients with very severe dysphagia do not seem to benefit from either treatment.

Supportive and symptomatic management of amyotrophic lateral sclerosis

The main aims in the care of individuals with amyotrophic lateral sclerosis (ALS) are to minimize morbidity and maximize quality of life. Although no cure exists for ALS, supportive and symptomatic care provided by a specialist multidisciplinary team can improve survival. The basis for supportive management is shifting from expert consensus guidelines towards an evidence-based approach, which encourages the use of effective treatments and could reduce the risk of harm caused by ineffective or unsafe interventions. For example, respiratory support using noninvasive ventilation has been demonstrated to improve survival and quality of life, whereas evidence supporting other respiratory interventions is insufficient. Increasing evidence implicates a causal role for metabolic dysfunction in ALS, suggesting that optimizing nutrition could improve quality of life and survival. The high incidence of cognitive dysfunction and its impact on prognosis is increasingly recognized, although evidence for effective treatments is lacking. A variety of strategies are used to manage the other physical and psychological symptoms, the majority of which have yet to be thoroughly evaluated. The need for specialist palliative care throughout the disease is increasingly recognized. This Review describes the current approaches to symptomatic and supportive care in ALS and outlines the current guidance and evidence for these strategies.

Serious and long-term adverse events associated with the therapeutic and cosmetic use of botulinum toxin

Although botulinum toxin is generally considered safe, its widespread use and the constantly expanded indications raise safety issues. This study aimed to review the serious and long-term adverse events associated with the therapeutic and cosmetic use of botulinum toxin. Serious adverse events included dysphagia, respiratory compromise, generalized muscle weakness, marked bilateral ptosis, pseudoaneurysm of the frontal branch of the temporal artery, necrotizing fasciitis, sarcoidal granuloma, Fournier gangrene, and cervical kyphosis. Death was attributed to botulism or anaphylactic shock. In conclusion, botulinum toxin may cause serious adverse events, which are more common after its therapeutic use, but can also be noticed after its cosmetic use. Thorough knowledge of the anatomy of the treated muscles and of the pharmacology of the drug is imperative to avoid serious adverse events.

The use of botulinum toxin injections to manage drooling in amyotrophic lateral sclerosis/motor neurone disease: a systematic review

Difficulty in managing oral secretions is commonly experienced by patients with amyotrophic lateral sclerosis (ALS)/motor neurone disease (MND) and associated bulbar weakness including dysphagia. There are no definitive evidence-based treatment guidelines to manage the distressing symptom of drooling. We reviewed the evidence for the effectiveness of botulinum toxin injections to reduce saliva in ALS/MND. The search strategy was conducted in four stages: (1) electronic search of relevant databases, (2) hand searches of all international ALS/MND symposium journals, (3) email request to MND care centres in the UK and Ireland, and (4) hand searching of reference lists. All studies were critically appraised and relevant data extracted. Botulinum toxin type A and type B were analysed separately. Due to heterogeneity, it was not possible to calculate a pooled estimate of effect. Twelve studies met the inclusion criteria (9 for type A and 3 for type B). Only two randomised controlled trials were identified. Study sample sizes were small with a mean of 12.5 subjects. The most frequently reported outcomes were weight of cotton rolls and number of tissues used. All studies claimed the intervention tested was effective, but only seven studies (4 for type A and 3 for type B) reported statistically significant differences. Although there is evidence to suggest that botulinum toxin B can reduce drooling, the evidence base is limited by a lack of randomized controlled trials. Evidence to support the use of botulinum toxin A is weaker. Larger trials will help remove the uncertainty practitioners face in treating this disabling symptom.

Rehabilitation of motor neuron disease

Amyotrophic lateral sclerosis (ALS), the most common adult motor neuron disease, is an acquired disorder that results in loss of function in multiple domains. Although there is no treatment that can halt or reverse this progressive condition, there are many opportunities for interventions that can lead to improved quality of life for the patient and caregiver. Physical and occupational therapy can assist with mobility and activities of daily living. Interventions by speech pathology can optimize nutrition and communication. Respiratory function can be managed noninvasively or invasively. Depression, hopelessness, anxiety, and other mental health issues can and should be aggressively addressed and treated. Many symptoms such as pseudobulbar affect, sialorrhea, constipation, spasticity, and cramps can be treated effectively with medications. Spirituality and religion are important issues to address, as are end-of-life concerns, including advance directives, hospice, and the dying process. In contrast to the discouraging view that "there is nothing we can do," a broad approach to management, through collaboration with a multidisciplinary team, will permit the ALS physician to make a meaningful difference in the lives of individuals living with ALS.

A new member of the multidisciplinary ALS team: the otolaryngologist

The multidisciplinary approach to treatment of amyotrophic lateral sclerosis (ALS) has improved the overall care of patients suffering from this disease ( 1 , 2 ). This approach typically has included neurologists, physiatrists, occupational therapists, respiratory therapists and speech therapists. Dysphonia, dysarthria, and dysphagia are three of the most common bulbar manifestations of ALS, and are often the presenting symptoms in bulbar-onset patients. Despite this, otolaryngologists are often not included in ALS management until a tracheostomy is considered. The otolaryngologist can play an important role in early diagnosis and subsequent management of bulbar manifestations of ALS, and would be a valuable member of the multidisciplinary team.

Dysphagia and aspiration in children

Aspiration is a significant cause of respiratory morbidity and sometimes mortality in children. It occurs when airway protective reflexes fail, especially, when dysphagia is also present. Clinical symptoms and physical findings of aspiration can be nonspecific. Advances in technology can lead to early diagnosis of dysphagia and aspiration, and, new therapeutic advances can significantly improve outcome and prognosis. This report first reviews the anatomy and physiology involved in the normal process of swallowing. Next, the protective reflexes that help to prevent aspiration are discussed followed by the pathophysiologic events that occur after an aspiration event. Various disease processes that can result in dysphagia and aspiration in children are discussed. Finally, the various methods for diagnosis and treatment of dysphagia in children are reviewed.

Drooling: are botulinum toxin injections into the major salivary glands a good treatment option?

There are several treatment options available for drooling; botulinum toxin injections into the major salivary glands are one. There is no consensus as to how many and which glands should be injected. A research project on this topic was terminated because of adverse effects. Individual results and the adverse effects are described and discussed in this article. Six individuals with cerebral palsy were randomly allocated to 2 treatment groups, with five individuals receiving ultrasound-guided injections to parotid and submandibular glands and one receiving injections to the submandibular glands only. Reduction of observed drooling was registered in 3, while 4 patients reported subjective improvement (Visual Analog Scale). Two participants reported adverse effects, including dysphagia, dysarthria, and increased salivary viscosity. Injections with botulinum toxin can be a useful treatment option but there is a risk of adverse effects. Multidisciplinary evaluation and informed discussions with patients/caregivers are important factors in the decision-making process.

Does motor performance matter in botulinum toxin efficacy for drooling?

The aim of this study was to define factors that influence therapy outcome of submandibular botulinum toxin injections for drooling in children with cerebral palsy or mental disability. We postulated that differences in response may be explained by the variation of dysfunctions in the various cerebral palsy subtypes. Prospectively collected data were evaluated of 80 spastic and 48 dyskinetic children, of whom 70% had an IQ of <70. In addition, the data of 23 fully ambulant children with mental disability only were examined. Flow and Drooling Quotient were assessed at baseline and at 8 weeks after injection. After treatment, both the Drooling Quotient and submandibular flow decreased in all children. Morbidity associated with the procedure was limited. Ninety-three children responded to botulinum. Decrease of submandibular flow in these children was associated with reduction of parotid flow. In those who did not respond to therapy, spread across all 3 diagnostic classifications, parotid flow increased after injection. Response failure is characterized by increased parotid flow after injection; however, the precise role of parotid flow in therapy failure remains unclear. We cannot predict who will respond to botulinum toxin to treat drooling.

Dysarthria in amyotrophic lateral sclerosis: A review

Dysarthria is a motor disorder of speech characterized by abnormalities of the articulation and intelligibility of speech. Phonation and the rate of facial movements may also be affected. Understanding the nature and course of dysarthria in amyotrophic lateral sclerosis (ALS) is important because loss of communication prevents patients from participating in many activities, may lead to social isolation, and reduces the quality of life. The goal of management of dysarthria in ALS patients is to optimize communication effectiveness for as long as possible. The information about dysarthria in ALS is dispersed in physiological, pathological, speech therapy, otorhinolaringological and neurological publications. This review summarizes the current state of knowledge on the clinical features, differential diagnosis, pathophysiology, investigations and management of dysarthria in ALS patients. There is a need to compare the different methods used to assess dysarthria and for controlled clinical trials to assess therapeutic strategies.

A musculoskeletal ultrasound course for physical medicine and rehabilitation residents

Musculoskeletal ultrasound is an imaging modality that can be used to evaluate nerve, tendon, muscle, ligament, and joint disorders and to guide therapeutic procedures. A growing proportion of physiatrists are interested in musculoskeletal ultrasound as demonstrated by the increasing number of musculoskeletal ultrasound articles published in physical medicine and rehabilitation journals and quantity of musculoskeletal ultrasound courses and workshops at physical medicine and rehabilitation conferences. The Mayo Clinic (Rochester, MN) Physical Medicine and Rehabilitation residency program developed a musculoskeletal ultrasound course for their physical medicine and rehabilitation residents, which was implemented in 2008. A detailed description of the course is provided in this article. In addition, results from a premusculoskeletal ultrasound course and postmusculoskeletal ultrasound course practical and written test are presented, and the results of a postmusculoskeletal ultrasound course resident survey are discussed. This information can be used by other physical medicine and rehabilitation residency programs to assist in the creation of their own musculoskeletal ultrasound course.