Cannabinoids can help to treat motor symptoms like dystonia in patients with early-onset Huntington’s disease, a small case study reports.
The study, “Cannabinoids for Treatment of Dystonia in Huntington’s Disease,” appeared in the Journal of Huntington’s Disease.
Huntington’s disease is characterized by movement disorders, cognitive deterioration, and behavioral changes. Patients show several different types of motor problems, including chorea — the most common symptom — and dystonia, which has a high incidence both in juvenile cases and throughout disease progression.
Chorea refers to involuntary, abrupt, and irregular spasmodic movements, whereas dystonia is the painful and prolonged muscle contractions that cause involuntary and repetitive twisting.
While there are several guidelines for treating most motor symptoms in Huntington’s patients, no clear recommendation recommendation exists for dystonia.
Numerous studies over the past decade have looked at cannabis and on its active components — known as cannabinoids — as a potential treatment for movement disorders in several neurodegenerative conditions.
To date, three randomized, placebo-controlled trials have evaluated the potential motor benefits of cannabinoids in Huntington’s patients. Only one reported an effect on chorea and potential improvements on behavior.
Data regarding the benefits of cannabinoids on Huntington’s motor symptoms are considered rare and inconsistent.
Researchers evaluated the clinical benefits of cannabinoids in seven patients with early-onset Huntington’s disease, with severe dystonia as the main motor symptom. Alternative therapies used to address dystonia were either ineffective or not possible (due to non-motor symptoms) in these patients.
Four men and three women were recruited and followed at two Huntington centers — one in Germany and another in Austria – and five of the seven were in advanced disease stages. Patients’ average age was 28.3 years (age range, 14 to 40), and the average of disease duration was 11 years.
Since this was not an open-label study, different cannabinoid treatments were given to patients according to the treating physician’s experience and health resources; there is a large price range among cannabinoids.
Patients’ motor function was assessed through the Unified Huntington’s Disease Rating Scale (UHDRS) motor score, which includes the subscores of dystonia and chorea.
Cannabinoid treatment significantly improved motor symptoms in all patients, which was associated with dystonia improvement. No relevant changes in the chorea subscore were observed in these patients.
Some patients and/or patients’ relatives also reported functional improvements and better quality of life. A reduction in apathy, hypersalivation, and irritability (in three patients experiencing irritability) was also reported.
No relevant adverse effects were reported, except for a temporary sedative effect on one patient at the beginning of treatment.
Although this was not a randomized clinical trial, the case study’s results suggest that “there are beneficial symptomatic motor effects in HD patients with dystonia as the leading motor syndrome and also some beneficial effects on behavioral disturbances,” the researchers wrote.
“A double-blind, placebo-controlled trial appears to be highly warranted to establish definitely the symptomatic effects of cannabinoids for dystonia in HD since dystonia is a frequent and disabling symptom,” they added.