Patients with insomnia may experience a reduction in latency to persistent sleep time after undergoing vestibular stimulation, a novel treatment option that has few adverse effects.
SEATTLE—Vestibular stimulation can reduce latency to persistent sleep time and should be considered an option for treating patients with insomnia, according to a study presented at the 23rd Annual Meeting of the Associated Professional Sleep Societies.
“Various remedies have sought to alleviate this problem, including medication, behavioral therapy, alcohol, and herbal products,” Gary K. Zammit, PhD, President and CEO of Clinilabs, Inc, in New York City, and colleagues stated. He and his colleagues tested the ability of Respironics’ VirtuSom device (VSOM) to decrease latency to persistent sleep time, which was defined as time to fall asleep and stay asleep for 20 consecutive epochs as measured on full polysomnography.
The researchers screened 890 participants (ages 21 to 50) by telephone and included 349 who could be classified as “normal sleepers” (average self-reported sleep opportunity of 7.5 to 9.0 hours and a habitual bedtime between 9:00 pm and 1:00 am that did not vary by more than one hour at least five nights per week). Participants were instructed to keep a sleep diary and wear an actigraph for three to five days. The Multiple Sleep Latency Test (MSLT) was given to those showing sufficient sleep opportunity, to eliminate possibility of residual sleep debt.
Variation Among Study Sites
Subjects (n = 282) with an average sleep onset latency on the MSLT of greater than 14 minutes were assigned to either a sham device or an active device, and were titrated to a comfortable therapy level. “The active device provided one hour of stimulation initiated at lights out, while the sham device looked and behaved identically, but gave no stimulation,” Dr. Zammit, who is also a Clinical Associate Professor in the Department of Psychiatry at Columbia University College of Physicians and Surgeons in New York City, commented. Participants received eight-hour polysomnography beginning five hours prior to their normal bedtime. Subjects and polysomnography technicians were blinded to the therapy.
Vestibular stimulation was well tolerated, and headache and skin irritation were the most common complaints, according to the investigators. Among seven study sites, VirtuSom effectively lowered latency to persistent sleep in all but one; the reason for this difference is unknown. “The data indicate that this site was statistically different from the other sites, and as such, it is appropriate to analyze the data with this site excluded,” Dr. Zammit stated.
VSOM Versus Sham Therapy
For the remaining six sites (n = 242), the mean latency to persistent sleep time in minutes among those randomized to VSOM was 44.9 (n =119), compared with 63.8 (n = 123) in the sham group.
For persons who were treated, mean latency to persistent sleep times were 42.6 (n = 113) in the VSOM group, versus 64.9 (n = 129) in the sham group. “Vestibular stimulation was associated with a significantly shorter latency to persistent sleep time compared with the sham therapy, and the results are consistent with studies involving pharmacotherapy for the treatment of insomnia,” Dr. Zammit and coauthors stated.
Other sleep variables observed included total sleep time in the first hour after lights out, subjective sleep onset latency, and total sleep time in the first two hours after lights out. No significant differences were shown among these variables.
“This technology appears to show promise for the treatment of insomnia and may be a valuable tool, along with others, that may assist doctors in treating patients who suffer from insomnia,” Dr. Zammit told Neurology Reviews. Future studies for this treatment device are planned.
—Laura Sassano