Onabotulinumtoxin A Treatment of Drooling in Children with Cerebral Palsy: A Prospective, Longitudinal Open-Label Study

Comparing botulinum toxin and 4-duct ligation for Sialorrhea in children - A systematic review

INTRODUCTION

Sialorrhea or drooling can result in physical and psychosocial complications, such as aspiration and social isolation. Treatment options include botulinum toxin into the salivary glands and 4-duct ligation (i.e., simultaneous ligation of the bilateral parotid and submandibular ducts). This systematic review aimed to compare the efficacy and complication rates of botulinum toxin and 4-duct ligation for the treatment of drooling in children.

METHODS

Following PRISMA guidelines, PubMed, Embase, Web of Science, and Cochrane Library were searched from inception through June 17, 2021 for studies examining the efficacy of botulinum toxin or 4-duct ligation for drooling in children. Data were summarized by pooled counts, percentages, and means. Complication rates were compared by a chi-squared test.

RESULTS

A total of 22 studies (n = 606) examining botulinum toxin and 5 studies (n = 124) examining 4-duct ligation were included. From 12 botulinum toxin studies (n = 211), mean drooling frequency and severity scores was 7.5 at baseline. Mean difference from baseline was -2.6 (n = 92) at 4 weeks follow-up, -2.1 at 8 weeks (n = 41), -2.1 at 12 weeks (n = 56), and - 2.1 at 16 weeks (n = 58). From 4 4-duct ligation studies (n = 103), mean baseline drooling frequency and severity score was 8.4. Mean difference was -3.7 at mean follow-up of 35.6 months (n = 103). Eighteen botulinum studies (n = 343) recorded 53 (15.5 %) complications, including thickened saliva (n = 9), dysphagia (n = 4), and cheek abscesses (n = 4). Four 4-duct ligation studies (n = 108) recorded 25 (23.1 %) complications, including parotid gland swelling (n = 4), aspiration pneumonia (n = 3), and oxygen desaturation (n = 3). There was no statistically significant difference in complication rates between botulinum toxin and four-duct ligation (p = 0.065).

CONCLUSION

Botulinum toxin injection and 4-duct ligation are both effective in improving sialorrhea in children and have comparable complication rates.

Comparing the evidence for botulinum neurotoxin injections in paediatric anterior drooling: a scoping review

Paediatric anterior drooling has a major impact on the daily lives of children and caregivers. Intraglandular botulinum neurotoxin type-A (BoNT-A) injections are considered an effective treatment to diminish drooling. However, there is no international consensus on which major salivary glands should be injected to obtain optimal treatment effect while minimizing the risk of side effects. This scoping review aimed to explore the evidence for submandibular BoNT-A injections and concurrent submandibular and parotid (i.e. four-gland) injections, respectively, and assess whether outcomes could be compared across studies to improve decision making regarding the optimal initial BoNT-A treatment approach for paediatric anterior drooling. PubMed, Embase, and Web of Science were searched to identify relevant studies (until October 1, 2023) on submandibular or four-gland BoNT-A injections for the treatment of anterior drooling in children with neurodevelopmental disabilities. Similarities and differences in treatment, patient, outcome, and follow-up characteristics were assessed. Twenty-eight papers were identified; 7 reporting on submandibular injections and 21 on four-gland injections. No major differences in treatment procedures or timing of follow-up were found. However, patient characteristics were poorly reported, there was great variety in outcome measurement, and the assessment of side effects was not clearly described.   Conclusion: This review highlights heterogeneity in outcome measures and patient population descriptors among studies on paediatric BoNT-A injections, limiting the ability to compare treatment effectiveness between submandibular and four-gland injections. These findings emphasize the need for more extensive and uniform reporting of patient characteristics and the implementation of a core outcome measurement set to allow for comparison of results between studies and facilitate the optimization of clinical practice guidelines. What is Known: • There is no international consensus on which salivary glands to initially inject with BoNT-A to treat paediatric drooling. What is New: • Concluding on the optimal initial BoNT-A treatment based on literature is currently infeasible. There is considerable heterogeneity in outcome measures used to quantify anterior drooling.and clinical characteristics of children treated with intraglandular BoNT-A are generally insufficiently reported. • Consensus-based sets of outcome measures and patient characteristics should be developed and implemented.

Botulinum Toxin A in the Management of Pediatric Sialorrhea: A Systematic Review

OBJECTIVE

Botulinum toxin A is known to be effective and safe in managing sialorrhea in pediatric patients; however, there is no consensus on a protocol for optimal injection sites and appropriate dosing for injection.

METHODS

This review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocol. PubMed, EMBASE, and other databases were queried to identify articles that evaluated botulinum toxin type A for the treatment of sialorrhea in the pediatric population. A total of 405 studies were identified. After applying inclusion and exclusion criteria, 31 articles were included for review.

RESULTS

A total of 14 studies evaluated 2-gland injections, and 17 studies evaluated 4-gland injections. Of the 31 studies included, one study assessed incobotulinumtoxinA (Xeomin®) the remaining all used onabotulinumtoxinA (Botox®). For 2-gland injection studies, a combined total of 899 participants were reviewed, where 602 participants received 50 units into their submandibular glands, while 262 participants received 30 to 50 units. Among 4-gland injection studies, there was a combined total of 388 participants, with the most prevalent dosage utilized being 60 to 100 units in 230 participants, followed by 100 units total in 77 participants. The most common adverse event was dysphagia which resolved in nearly all cases. Three studies aimed to examine 2-gland versus 4-gland injections, with 2 of the studies concluding 4-gland injection was superior.

CONCLUSIONS

The strength of evidence suggests that the dosing of 50 units total of onabotulinumtoxinA to the submandibular glands is safe and effective in the pediatric population. For 4-gland injections, bilateral submandibular and parotid gland injections of 60 to 100 units total is the safe and effective dosage. There is no substantial evidence comparing 4-gland injections to 2-gland injections, but research thus far suggests 4-gland injections to be superior. Future study is needed to evaluate incobotulinumtoxinA and abobotulinumtoxinA dosages in the pediatric population.

Botulinum Toxin Injections for Treatment of Drooling in Children with Cerebral Palsy: A Systematic Review and Meta-Analysis

Background: We aimed to review and analyse the effectiveness and safety of botulinum toxin type A (BoNT-A) injections for drooling in children with cerebral palsy. Data sources: We searched the EMBASE, MEDLINE, Cochrane Database of Systematic Reviews, and Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library) databases from inception to January 2020. Methods: We included randomized controlled trials and observational studies which (1) involved children with cerebral palsy, (2) used BoNT-A for control of drooling, and (3) provided quantitative evaluations of drooling before and after intervention with BoNT-A. Results: Twenty-one trials met the inclusion criteria. Most studies showed that BoNT-A injections are safe and efficacious as a treatment for drooling in children with cerebral palsy. Four trials had sufficient data to pool the results for the meta-analysis. Both the drooling quotient (p = 0.002) and drooling Ffrequency and severity scale (p = 0.004) supported this conclusion. Conclusion: BoNT-A injections are a safe, reversible, effective treatment for drooling control in children with cerebral palsy that can offer effectiveness for more than 3 months with few side effects. The dosage of BoNT-A should not exceed 4 units/kg. Further studies are required to determine the optimal dosage and target glands.

Placebo-Controlled Clinical Trial of IncobotulinumtoxinA for Sialorrhea in Children: SIPEXI

BACKGROUND AND OBJECTIVES

To investigate the efficacy and safety of repeated injections of incobotulinumtoxinA (incoBoNT/A) for treatment of chronic sialorrhea (drooling) associated with neurologic disorders (e.g., cerebral palsy, traumatic brain injury) or intellectual disability in children and adolescents in a prospective phase III study (SIPEXI [Sialorrhea Pediatric Xeomin Investigation]).

METHODS

The study enrolled 2- to 17-year-old patients with sialorrhea due to neurologic disorders or intellectual disability. Patients received body weight-dependent doses of incoBoNT/A (20-75 U). A main period with 1 injection cycle (placebo-controlled, double-blind, 6- to 17-year-olds) was followed by an open-label extension with up to 3 further cycles. An additional cohort of 2- to 5-year-olds received active treatment throughout the study. Coprimary endpoints were the change in unstimulated salivary flow rate (uSFR) from baseline to week 4 and the carers' Global Impression of Change Scale (GICS) rating at week 4. Adverse events were recorded.

RESULTS

In the main period, 220 patients aged 6-17 years were randomized and treated (148 patients in incoBoNT/A group, 72 patients in placebo group). A total of 35 patients aged 2-5 years received incoBoNT/A (no placebo). A total of 214 patients aged 6-17 years and 33 patients aged 2-5 years continued treatment in the open-label extension period. For the 6- to 17-year-olds, a significant difference between incoBoNT/A and placebo was seen in mean uSFR decrease (difference -0.06 g/min; p = 0.0012) and the carers' GICS rating (difference 0.28 points; p = 0.032) at week 4, in favor of active treatment. The secondary endpoints consistently supported these results. A sustained benefit was observed during the extension. Incidences of adverse events were comparable between incoBoNT/A and placebo and did not increase notably with repeated injections. The most common adverse events were respiratory infections. Efficacy and safety were also favorable in the uncontrolled cohort of 2- to 5-year-olds.

DISCUSSION

Both co-primary efficacy endpoints were reached and superiority of incoBoNT/A over placebo was confirmed. IncoBoNT/A (up to 75 U, up to 4 cycles) is an effective and well-tolerated treatment for sialorrhea associated with neurologic disorders in children.

TRIAL REGISTRATION INFORMATION

Clinicaltrials.gov: NCT02270736 (clinicaltrials.gov/ct2/show/results/NCT02270736); EU Clinical Trials Register: 2013-004532-30 (clinicaltrialsregister.eu/ctr-search/search?query=2013-004532-30).

CLASSIFICATION OF EVIDENCE

This study provides Class I evidence that injection of incobotulinumtoxinA decreases drooling in children aged 6 to 17 years with neurologic disorders.

A critical review of incobotulinumtoxinA in the treatment of chronic sialorrhea in pediatric patients

INTRODUCTION

Sialorrhea, also known as hypersalivation, ptyalis, or drooling, results in physical and psychosocial complications that may have a significant negative impact on quality of life for both the patient and their caregiver. The goal of pharmacological treatment is to reduce excessive salivary flow, while maintaining a moist and healthy oral cavity; until recently, however, few of the agents used to treat chronic sialorrhea have been approved in pediatric patients.

AREAS COVERED

This article summarizes early evidence for the use of botulinum neurotoxin A formulations in the treatment of children/adolescents with chronic sialorrhea, and findings of the recently completed phase III trial of incobotulinumtoxinA in this indication. Alternative therapies are also briefly discussed.

EXPERT OPINION

IncobotulinumtoxinA is the first botulinum neurotoxin A to be approved for the treatment of chronic sialorrhea in children and adults, following the results of phase III trials that demonstrate the efficacy and safety of the drug in these patients. The authors expect that the positive findings will result in updates to clinical guidelines for the treatment of children with chronic sialorrhea.

ABBREVIATIONS

AE, adverse event; AESI, adverse event of special interest; BoNT/A, botulinum neurotoxin A; CI, confidence interval; CP, cerebral palsy; DIS, drooling impact scale; DQ, drooling quotient; DSFS, Drooling Severity and Frequency Scale; GICS, Global Impression of Change Scale; LS, least squares; mTDS, modified Teacher's drooling scale; NR, not reported; PD, Parkinson's disease; SAE, serious adverse event; SE, standard error; SIAXI, Sialorrhea in Adults Xeomin Investigation; SIPEXI, Sialorrhea Pediatric Xeomin Investigation; SNAP-25, synaptosomal associated protein-25; TBI, traumatic brain injury; TDS, Teacher Drooling Scale; USA, United States of America; uSFR, unstimulated Salivary Flow Rate; VAS, visual analog scale.

Cumulative Efficacy of Longitudinal Repeat Salivary Gland OnabotulinumtoxinA Injection: A Retrospective Study

AIM

We hypothesized that repeat onabotulinumtoxinA (BTX-A) injections to salivary glands would have a cumulative effect on drooling, leading to prolonged efficacy duration.

METHODS

We retrospectively reviewed medical records and conducted a telephone survey of individuals treated with BTX-A to the salivary glands to investigate ongoing efficacy or adverse effects. Outcome measures were duration of decrease in drooling and adverse events. The main independent variable was the number of injections. We identified 52 consecutive individuals (26 females) with cerebral palsy with an average age of 9 yrs, 3 mos ± 5 yrs 2 mos, who had received BTX-A for sialorrhea.

RESULTS

Linear regression analysis showed that each additional injection resulted in the duration of efficacy being 0.68 mos longer (P < 0.001, R2 = 0.47). Age, sex, Gross Motor Function Classification System level, presence of tube feeding, presence of tracheostomy, gastroesophageal reflex, seizures, and concurrent intramuscular injections seizures were not significant contributors to the association between injection number and efficacy duration (F (6, 45) = 1.01, P = 0.431).

INTERPRETATION

There may be a cumulative effect of BTX-A injections to the salivary glands, resulting in longer periods of efficacy with consecutive injection.

Oral health effects of botulinum toxin treatment for drooling: a systematic review

Background

Drooling is a major morbidity in several neurological diseases. Intraglandular botulinum neurotoxin (BoNT) injections have been used to manage this condition. However, by decreasing salivary flow, BoNT injections may result in an increased risk of caries and other oral adverse effects. In this study, we aimed to assess whether, in patients with drooling, intraglandular BoNT injections are associated with increased dental caries development, modifications on salivary composition (oral pH, buffering capacity and osmolality) and cariogenic bacterial load.

Material and Methods

We performed a systematic review, searching PubMed, CENTRAL, Web of Science, and Scopus for all experimental and observational studies reporting on adverse effects of intraglandular BoNT injections in patients with drooling. Primary study selection, quality assessment, and data extraction were independently performed by two researchers. No studies were excluded based on their language, publication status or date of publication. Studies’ quality was based on revised Cochrane Risk of Bias tools. Meta-analysis was not performed.

Results

We retrieved 1025 studies, of which 5 were included. Two studies were two randomized controlled trials and three quasi-experimental studies. None of the included studies found BoNT injections to be associated with dental caries development or with significant reductions in oral pH. One of the included primary studies even observed an increase in salivary buffer capacity. One study found an increase in Lactobacilli counts. As for the risk of bias, two studies were classified as having a critical risk, two as high risk and one as having some concerns.

Conclusions

Currently, there is no evidence that, in patients with drooling, BoNT injections associate with increased risk of dental caries or disturbances in oral pH or salivary buffering capacity. However, the included primary studies had important limitations and differences in their methodologies.

Key words:Neurological diseases, drooling, sialorrhea, botulinum toxin, oral health, caries, saliva.

Safety of combined salivary gland and multilevel intramuscular onabotulinumtoxinA injections with and without ethanol in pediatric patients with cerebral palsy: A retrospective study

OBJECTIVE

To evaluate the safety of combining salivary gland onabotulinumtoxinA (BTX-A) injections for sialorrhea with intramuscular BTX-A injections for spasticity in the same procedure.

DESIGN

A retrospective cohort study in a tertiary hospital center. Patients selected were younger than 20 years, diagnosed with cerebral palsy, and received their first salivary gland BTX-A injection between March 2011 and July 2015. Chart review and telephone interviews were performed. The primary outcome measure was the rate of adverse events after combined BTX-A injections into salivary glands and muscles. The secondary outcome measure was the efficacy of injections, as reported by patients.

RESULTS

Twenty-five of the 52 selected patients received salivary gland BTX-A injections only, and 27 received concurrent salivary gland and multi-level intramuscular chemodenervation with BTX-A with or without alcohol. The rate of adverse events was < 10% in both groups; 4% in "Salivary Only Group" and 7% in the "Salivary + Multilevel Intramuscular Chemodenervation with BTX-A group (with or without alcohol)". Both approaches were equally effective in meeting their goals of salivary injections (> 50% improvement for at least two months). In the "salivary only" and in the "salivary + multi-level intramuscular" group, 76 and 85% of the patients reached their goals respectively.

CONCLUSIONS

Combining BTX-A injections for sialorrhea with multilevel intramuscular BTX-A injections (with or without alcohol) appears to be safe and effective and allows treatment of patients for both conditions simultaneously.

BOTOX-A injection of salivary glands for drooling

BACKGROUND AND PURPOSE

Drooling is a challenging entity to manage. Botulinum toxin A (BOTOX-A) infiltration of salivary glands is a promising alternative to surgical treatment. This study aims to assess the outcome of BOTOX-A salivary glands infiltration in children with drooling.

METHODS

Patients treated between January 2012 and March 2015 were enrolled. BOTOX-A was injected in the parotid and submandibular glands under ultrasound control and general inhalational anesthesia. The outcome was evaluated through the DSFS: Drooling Severity (1-best to 5-worst) and Frequency (1 to 4) Scale, that was applied before treatment, and 1-, 3-, and 6-month after injection. The inclusion criteria were a DSS ≥4 and/or DFS ≥3. Statistical significance was set at 5%.

RESULTS

There were 17 patients aged 12.1±5.1 [4-19]years, all of them with neurologic impairment. After the first injection, 13 (76.5%) patients had reduction of the severity (S) and 12 (70.6%) of the frequency (F) scale; in 6 (35.5%) patients drooling resolved completely. Pre-treatment S+F score was 8.59±0.71 [7-9]; it decreased significantly to 4.65±2.32 (p=0.001) at 1-month post-injection evaluation. At 3-month and 6-month the scores were also significantly lower than the pre-treatment one (4.00±1.96, p=0.002; 5.36±2.20, p=0.005; respectively), but there was a significant increase between the 3-month and 6-month evaluations (p=0.01). With a follow-up of 20.1±9.2 [4-38] months, 4 out of the 13 successful injections needed a second one after 7.5±3.1 [3-10] months. The patient with the longest time not requiring re-injection had 28months of follow-up. One (6%) patient presented mild dysphagia that regressed spontaneously. All but two (88%) parents/caregivers would repeat the treatment.

CONCLUSIONS

BOTOX-A seems to be an effective minimal invasive treatment for drooling with few complications. After 6months the need for re-injection becomes substantial but it may not be necessary for several months. Further studies are needed to establish the most effective dosage and frequency of injections.

LEVEL OF EVIDENCE

IV.

Negative effects of submandibular botulinum neurotoxin A injections on oral motor function in children with drooling due to central nervous system disorders

AIM

The aims of this study were: (1) to determine the incidence and nature of adverse effects on oral motor function after first injections of botulinum neurotoxin A (BoNT-A) in submandibular glands for excessive drooling in children with central nervous system disorders; and (2) to identify independent predictors of these adverse effects.

METHOD

A cohort study involved 209 children (123 males, 86 females, aged 4-27y, median 8y 4mo), who received submandibular BoNT-A injections for drooling. Adverse effects were categorized into swallowing, eating, drinking, articulation, and other problems. Univariable logistic regression was used to study differences in patients with and without adverse effects. Possible predictors were identified using multivariable logistic regression.

RESULTS

Transient adverse effects occurred in 33% of the 209 BoNT-A treatments. Almost 80% of these were mild, versus 8.7% severe. Approximately 54% of the adverse effects spontaneously resolved within 4 weeks; 3% still existed after 32 weeks. A diagnosis of cerebral palsy, higher range of BoNT-A dosage, and a pre-treatment drooling quotient <18% were found to be independent predictors of adverse effects.

INTERPRETATION

Before using submandibular BoNT-A injections for drooling, potential adverse effects should be discussed. Oral motor function needs to be monitored, because existing dysphagia may be worsened. The identified clinical predictors could be helpful to optimize patient selection.

Oral hygiene aspects in a study of children and young adults with the congenital and childhood forms of myotonic dystrophy type 1

The primary aim was to study the interaction between oral hygiene, oral care, saliva production, and oral motor function in individuals with myotonic dystrophy type 1 (DM1). A secondary aim was to study how oral hygiene, oral care, and saliva flow rate are affected by gender, age, and subgroup of DM1 in this study population. The study comprised 52 individuals, seven to 29 years of age, divided into two subgroups of DM1, the congenital (N = 24) and childhood-onset forms (N = 28). A combined dental and oral motor examination was performed and the participants or caregivers answered a questionnaire with questions about general health and disabilities, medication, dental care, and oral health. Sixteen individuals with a plaque-, gingivitis-, or calculus-index score of 5-6 were considered to have poor oral hygiene. There were no significant differences between subgroups (age, gender, or form of DM1) in terms of the occurrence of calculus, gingivitis, plaque, or saliva flow rate. The mean value of the unstimulated whole saliva flow rate was 0.7(±0.44) mL/min. An open mouth at rest and oral motor dysfunction were frequent findings. The majority of Swedish children and young adults with the congenital or childhood form of DM1 have fair or poor oral hygiene, with a high occurrence of plaque and gingivitis. As a group, individuals with DM1 and poor oral hygiene have a higher frequency of caries and they report less satisfaction with their oral care at home and the quality of dental care received compared with those with good oral hygiene.

Botulinum toxin injections for chronic sialorrhoea in children are effective regardless of the degree of neurological dysfunction: A single tertiary institution experience

OBJECTIVE

To determine the effectiveness of submandibular salivary gland Botulinum Toxin Type-A (BTX-A) injection in the treatment of drooling in children with varying degrees of neurological dysfunction.

METHODS

A retrospective review of pre- and post-procedure drooling frequency and severity scores of patients receiving BTX-A between January 2008 and January 2013. Stratification to different subgroups of neurological impairment was performed according to Gross Motor Function Classification System (GMFCS) score. Drooling severity was assessed using Thomas-Stonell and Greenberg symptom questionnaires administered at time of initial consultation and 3 months after treatment.

RESULTS

48 sets of BTX-A injections in 26 patients with an average age of 9.45 years (range 7 months-18 years) were included in the study. Marked improvement in drooling was seen in 60.4% of patients, a marginal or brief improvement was seen in 20.8% and there was no improvement in 18.8%. No adverse events were reported following any of the BTX-A injections. BTX-A was safe and effective in the eight patients with pre-existing swallowing dysfunction. Subsequent drooling surgery was performed in 15 (57.7%) of the cohort, all 15 patients responded to BTX-A injections. In patients with Cerebral Palsy, there was no correlation between the severity of the neurological dysfunction as measured by the Gross Motor Function Classification System (GMFCS) score and the response to BTX-A treatment.

CONCLUSIONS

Injection of BTX-A to the submandibular glands of children with neurological disorders is a safe procedure and results in a reduction in drooling in the majority of patients. Children with severe neurological dysfunction respond to BTX-A injections as effectively as their less impaired peers and the degree of response does not appear to be associated with the severity of neurological disability. BTX-A injection is a good initial procedure when drooling surgery is being considered.