Electrical Stimulation May Help Treat Neurodegenerative Ataxias

Transcranial direct current stimulation (tDCS), a type of electrical stimulation directed at the brain and spine, may help treat the symptoms of rare movement disorders like neurodegenerative ataxias, according to a study published in the journal Neurology.

As these diseases cause a myriad of coordination, memory, and cognitive issues, the noninvasive therapy may offer a potential and novel treatment option for patients who have them.

"These diseases can be devastating, and no effective treatments are currently available for most of these disorders, so there is great interest in finding new treatments to help reduce symptoms," said study author Barbara Borroni, MD, of the University of Brescia in Brescia, Italy, in a recent comment.

For their study, investigators enrolled over 20 individuals with several types of ataxias that affected the cerebellar area of the brain; the patient population had an average age of 55 with a history of having the disease for an average of 13 years. The patients were split into 2 treatment groups. In 1 group, investigators administered electrical stimulation of the brain and spinal cord 5 days a week for the duration of 2 weeks. In the other group, patients received a sham stimulation where the electrodes were placed on the participant, but the electric current was powered down after 5 seconds.

Prior to the start of the study, at 2 weeks, 1 month, and 3 months post-treatment, participants were assessed with overall tests of ataxia, tests of hand and arm dexterity, and how quickly they could walk as well as tests on how their brains were responding to the treatment. This was followed up with a “wash out” period in which participants waited for the duration of 3 months before receiving the opposite treatment and taking the tests again.

Improvements were observed for every test in participants who were administered the stimulation treatment, while no improvement on any test was observed in those who received the sham stimulation. For instance, prior to the start of the study, participants were found to take about 9.4 seconds to walk 8 meters, but after 1 month of electrical stimulation treatment, they were found to only take about 7.8 seconds to complete the same task. No change in times were noted in those who had received the sham stimulation.

Another test evaluated how long it would take participants to place and remove pegs from a peg board to gage hand and arm coordination. Prior to the start of the study, participants were observed to take 53 seconds to complete the task, on average. The time to complete the task dropped to 47 seconds in those who had received the stimulation for 1 month; those who received the sham stimulation experienced no improvement.

The investigators report that the promising results lasted for a minimum of 3 months for participants. "The people who had milder symptoms of their disease showed the greatest improvement in their test scores, suggesting that this stimulation should be given at an early stage of the disease to be more effective," Dr. Borroni added.

The investigators admit that the study did have its limitations; one was the small number of participants. Additionally, those included in the study had several types of neurodegenerative ataxias. As such, the results may not be applicable to all individuals with these disorders.