Evidence for the effectiveness of botulinum toxin for sialorrhoea

IncobotulinumtoxinA for hypersalivation in patients with amyotrophic lateral sclerosis: an open-label single-centre study

The objective of this study is to discover whether incobotulinumtoxinA (inco) can reduce relative hypersalivation in patients with amyotrophic lateral sclerosis (ALS). 14 patients with ALS (8 males and 6 females, age 55.4 ± 16.3 years) received ultrasound-guided injection of inco 100 MU in both parotid glands and inco 50 MU in both submandibular glands. Saliva production was gravimetrically measured with three cotton rolls placed in the mouth. Weight increase after 5 min was measured on an electronic scale. Subjective saliva production was registered with drooling frequency scale (DFS) and drooling severity scale (DSS). Saliva production was gravimetrically reduced at week 4 (p = 0.04), week 8 (p = 0.01) but not after week 12 after BT application. DFS was reduced at week 4 (p = 0.04), week 8 (p = 0.02), but not after week 12. DSS was reduced at week 4 (p = 0.03), week 8 (p = 0.04) and week 12 (p = 0.04). Patients in our study did not experience changes in their swallowing patterns or any other safety-relevant events. Inco is effective and well tolerated for saliva reduction in patients with ALS for 8-12 weeks.

Pre- and Post-synaptic Effects of Botulinum Toxin A on Submandibular Glands

Intraglandular injection of botulinum toxin type A (BoNT/A) is an effective treatment for sialorrhea. Despite numerous experimental and clinical studies on inhibition of saliva section by BoNT/A, the proteolysis of synaptosomal-associated protein 25 (SNAP-25) following BoNT/A treatment has not yet been confirmed in the salivary gland after injection of BoNT/A. More important, it is not known whether BoNT/A exerts a direct effect in acinar cells. Here, we show that injection of BoNT/A into the rat submandibular gland (SMG) decreased salivary flow in a dose-dependent manner; the inhibitory effect lasted at least 4 wk, and salivary flow recovered to normal levels by 12 wk. During the inhibitory period, SMG neurons and synapses expressed lower levels of full-length SNAP-25, and cleavage of SNAP-25 was observed, as indicated by detection of reduced molecular weight SNAP-25 using Western blotting. In addition, the water channel aquaporin 5 (AQP5) was downregulated and abnormally distributed in rat SMG after injection of BoNT/A. The direct effects of BoNT/A on AQP5 expression and distribution were assessed in vitro to exclude the influence of BoNT/A-induced inhibitory neurotransmission. In stable GFP-AQP5-transfected SMG-C6 cells, treatment with BoNT/A reduced the cell surface protein level of AQP5 in a dose- and time-dependent manner without affecting total AQP5 protein expression. Cell surface biotinylation and immunofluorescence demonstrated translocation of AQP5 from the membrane to the cytoplasm, which was confirmed by decreased levels of AQP5 protein in the membrane fraction and increased levels in the cytoplasmic fraction, suggestive of AQP5 redistribution. Taken together, these results indicated that BoNT/A reversibly decreased saliva secretion in rat SMGs through not only the presynaptic SNAP-25 cleavage but also the postsynaptic AQP5 redistribution. These data provide the first evidence for a direct effect of BoNT/A on the salivary gland.

Treatment effects for dysphagia in Parkinson's disease: a systematic review

BACKGROUND

Dysphagia remains a common problem in Parkinson's disease (PD). Previous systematic reviews on therapy effects for oropharyngeal dysphagia in PD have shown a lack of evidence. In the past 5 years several placebo or sham-controlled trials with varying results have been published.

OBJECTIVE

The aim of this systematic literature review is to summarize and qualitatively analyze the published studies on this matter.

METHOD(S)

Studies published up to December 2013 were found via a systematic comprehensive electronic database search using PubMed, Embase, and The Cochrane Library. Two reviewers independently assessed the studies using strict inclusion criteria.

RESULT(S)

Twelve studies were included and qualitatively analyzed using critical appraisal items. The review includes rehabilitative (exercises, electrical stimulation, bolus modification etc.) and pharmacologic treatment. Some well-designed controlled trials were included. However, none of the included studies fulfilled all criteria for external and internal validity. A meta-analysis was not carried out as most of the studies were not of sufficient quality to warrant doing so.

CONCLUSION

Expiratory Muscle Strength Training (EMST) and Video-Assisted Swallowing Therapy (VAST) may be effective dysphagia treatments solely or in addition to dopaminergic therapy for PD. However, these preliminary results warrant further investigation concerning their clinical applicability, and further research should be based on randomized sham-controlled trials to determine the effectiveness and long-term effects of different therapies for dysphagia in PD.

Use of rimabotulinum toxin for focal hypertonicity management in children with cerebral palsy with nonresponse to onabotulinum toxin

OBJECTIVE

The aim of this study was to review the effect of rimabotulinum toxin (BoNT-B) for focal hypertonicity management in children with cerebral palsy and secondary nonresponse to onabotulinum toxin treated at the authors' tertiary care academic medical center.

DESIGN

A retrospective review of the medical treatment of children was conducted at the authors' institution (March 16, 2001, to August 2, 2002) using the key words botulinum toxin B and Myobloc (Solstice Neurosciences Inc, South San Francisco, CA). Demographic information was analyzed using descriptive statistics (number [percentage] and mean [range]). The Pearson χ test was used to evaluate differences in incidence of adverse events.

RESULTS

Eighty-two children had BoNT-B injections (116 treatments). Overall, 26.8% (19/71) of the children or their parents/guardians reported no or minimal response to the injections, with 89.5% (17/19) of these children having secondary nonresponse to onabotulinum toxin. Adverse events were frequent but did not require hospitalization of any patient. No significant differences were found in incidence of adverse events related to BoNT-B dosing, medical fragility, or Gross Motor Function Classification System level.

CONCLUSIONS

More than one-fourth of the children receiving BoNT-B injections had nonresponse, with most having previous nonresponse to onabotulinum toxin. Adverse events related to BoNT-B injections were frequent and unpredictable but not severe.

Evidence-based review and assessment of botulinum neurotoxin for the treatment of secretory disorders

Botulinum neurotoxin (BoNT) can be injected to achieve therapeutic benefit across a large range of clinical conditions. To assess the efficacy and safety of BoNT injections for the treatment of certain hypersecretory disorders, including hyperhidrosis, sialorrhea, and chronic rhinorrhea, an expert panel reviewed evidence from the published literature. Data sources included English-language studies identified via MEDLINE, EMBASE, CINAHL, Current Contents, and the Cochrane Central Register of Controlled Trials. Evidence tables generated in the 2008 Report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology (AAN) review of the use of BoNT for autonomic disorders were also reviewed and updated. The panel evaluated evidence at several levels, supporting BoNT as a class, the serotypes BoNT-A and BoNT-B, as well as the four individual commercially available formulations: abobotulinumtoxinA (A/Abo), onabotulinumtoxinA (A/Ona), incobotulinumtoxinA (A/Inco), and rimabotulinumtoxinB (B/Rima). The panel ultimately made recommendations for each therapeutic indication, based upon the strength of clinical evidence and following the AAN classification scale. For the treatment of axillary hyperhidrosis in a total of 923 patients, the evidence supported a Level A recommendation for BoNT-A, with a Level B recommendation for A/Abo and A/Ona and a Level U recommendation (insufficient data) for A/Inco and B/Rima. Five trials in 82 patients supported the use of BoNT in palmar hyperhidrosis, with a Level B recommendation for BoNT-A and a Level C recommendation for BoNT-B; individual formulations received a Level U rating due to insufficient data. BoNT (and all individual formulations) received a Level U recommendation for the treatment of gustatory sweating. Support for use of BoNT in sialorrhea was derived from eight trials in a total of 222 adults and children. Evidence supported a Level B recommendation for A/Abo, A/Ona, and B/Rima and a Level U recommendation for A/Inco. Evidence supported a Level B recommendation for A/Ona for the treatment of allergic rhinitis, based on two Class II studies in 73 patients. A lack of published studies for A/Abo, A/Inco, or B/Rima supported a Level U recommendation for those formulations. Further clarity on the optimal mode of administration and additional studies using other BoNT formulations are needed to fill current evidence gaps.