The neuroplasticity-sensitizing drug D-cycloserine did not further improve tinnitus bother in patients receiving computer-based cognitive training (CT), but it did help self-reported cognitive deficits compared with a placebo. These findings, which were published in JAMA Otolaryngology-Head & Neck Surgery (2015;141:18-26http://archotol.jamanetwork.com/article.aspx?articleid=1917537), are preliminary, as the study was small.
“We wanted to see if computer-based programs that exploit neuroplasticity help patients with tinnitus deal with the associated bother and cognitive difficulties that they're experiencing,” said senior author Jay F. Piccirillo, MD, a professor in the Department of Otolaryngology–Head and Neck Surgery at the Washington University School of Medicine in St. Louis.
The double-blind, randomized clinical trial included 30 participants age 35 to 65 who had subjective, unilateral or bilateral, nonpulsatile tinnitus for at least six months and a score of 30 or greater on the Tinnitus Handicap Inventory (THI). The study was conducted in the Clinical Outcomes Research Office at Washington University in St. Louis.
All participants were treated with an abbreviated computer-based CT program, working on the Brain Fitness Program for one hour a day, two days a week, for five weeks, instead of the usual regimen of one hour a day, five days a week, for eight weeks.
Half of the participants were randomized to receive a placebo, and the other half to receive D-cycloserine, which has shown mixed but encouraging results in augmenting learning therapies, Dr. Piccirillo and colleagues noted.
In future research, Dr. Piccirillo plans to include a larger sample size and have participants use the cognitive training program more often and over a longer time period, he said.
Richard Tyler, PhD, professor of otolaryngology–head and neck surgery and of communication sciences and disorders at the University of Iowa, said he doesn't think additional research examining the effects of D-cycloserine on tinnitus is needed.
“There's nothing in this study that suggests further study is necessary because the drug didn't work for helping tinnitus,” he said.
“There's an improvement in self-reported cognitive deficits unrelated to tinnitus, which is consistent with previous studies using the drug in patients who don't have tinnitus. One conclusion may be that this drug is good for all of us, too, as well as for the brain training.”
Samira Anderson, AuD, PhD, assistant professor in the Department of Hearing and Speech Sciences at the University of Maryland, said she'd like to see tests on processing speed and working memory, as this study focused on personal experiences of cognition.
“It was preliminary, so I'd want to see more before I was convinced,” she said. “But I thought it was interesting.”