Yale researchers, led by principal investigator Lawrence Scahill, associate professor at the School of Nursing and the Child Study Center at Yale School of Medicine, recently launched the four-year study.
One hundred twenty adults with TS will be randomly assigned to CBIT or a structured supportive psychotherapy program. Both treatments consist of 10 sessions with follow-up assessments at three- and six-month intervals. The primary outcome measure is the change in tic severity assessed by an independent evaluator blind to treatment assignment.
This $3 million grant complements an identical study funded last year by NIH to evaluate the same behavioral intervention in children. Other collaborating sites including the Johns Hopkins University, the University of California at Los Angeles and the University of Wisconsin at Milwaukee are conducting the study in children with TS. Together, the funding for the two studies amounts to $6 million. The informatics group at Yale is doing data management for both studies.
"This study is particularly exciting because it is the first time in psychiatry that the same behavioral intervention is being applied in a single disorder across the lifespan," notes Scahill, who is also the acting associate dean for scholarly affairs at the School of Nursing.
Tourette syndrome is a neurological disorder characterized by enduring motor and vocal tics. Motor tics are usually rapid and darting movements of face, head, neck and shoulders. However, the tics in TS may also involve the extremities and more complex movements that are purposeful in appearance. Vocal tics are usually simple sounds such as throat clearing, snorting or grunting or more complex sounds including the repetition of words or short phrases. The tics of TS fluctuate over time with a peak severity between the ages 10 and 12 years in most cases. For some patients, however, the tics persist into adulthood and may be associated with considerable distress or social and occupational impairment.
The current standard treatment for tic suppression is medication, particularly drugs that block dopamine in the brain. However, these medications often produce a dose-related range of adverse effects that may threaten compliance and result in premature termination of treatment, according to researchers. In addition, currently available medications rarely eliminate all tics. Given these limitations, adults with TS are often faced with a partial response to medication. Others choose not to use medication due to unacceptable side effects, so research is exploring non-pharmacological interventions.