A prospective, randomised controlled study comparing radiotherapy with botulinum toxin A as a treatment for drooling in ALS.

BACKGROUND:

Drooling is a common and invalidating symptom in patients with Amyotrophic Lateral Sclerosis (ALS). Radiotherapy and botulinum toxin injections are now well accepted as alternative treatment options to the more tradional and often disappointing drug management of this symptom. Still, a well-designed prospective and controlled trial to compare these two methods has never been performed.

OBJECTIVE:

To answer the question which treatment has preference when taking into account effectiveness and side effects.

METHODS:

In a prospective, randomized, controlled trial we will compare efficacy and tolerability of ultrasound-guided BTX-A injections in parotids and submandibular glands with radiotherapy performed by a single dosage of 7.0Gy bilateral to the parotid glands and the posterior parts of the submandibular glands. To evaluate the effect of treatment measurements will be performed at baseline and after 4, 12 and 36 weeks by the number of used paper handkerchiefs, a drool rating scale, a VAS-scale, ALSAQ-40 and ALS-FRSrevised. Side effects will also be strictly monitored by evaluation of bulbar function. Since the start of the study eleven patients have been included. Five patients were treated with radiotherapy (RT), five patients with botulinum toxin (BT) injection and one patient with both.

RESULTS:

A positive effect to initial treatment was 80% after RT versus 50% after BT. Retreatment of RT raised positive response to 100% and retreatment of BT raised response to 66%. The mean effect size was 48 days after RT versus 45 days after BT (range between one week and 4 months). As a result of both treatments xerostomia and changed viscosity of saliva were mentioned as side effects. No decrease of bulbar functions was observed.

CONCLUSIONS:

After treatment 10 patients were satisfied for at least a short period of time. No serious side effects were found. The effect of the treatments did not significantly differ in this small group of patients