Severe Tourette's Syndrome Is Associated with Increased Risk of Cervical Spine Disorders
By Mark Moran
October 7, 2021
Article In Brief
Movement disorders specialists should monitor patients with severe Tourette's syndrome and chronic tic disorders for cervical spine disorders. Although they are rare, these disorders can be quite disabling and damaging, said the authors of a new analysis.
Patients with severe Tourette's syndrome and/or chronic tic disorder (TS/CTD) have an increased risk of vascular and non-vascular cervical spine disorders, according to a study published online on August 23 in JAMA Neurology.
These individuals—especially those with severe repetitive neck extension tics (so-called “whiplash” tics)—should be monitored by a collaborative team of movement disorder specialists, the study authors said. Potential nonvascular cervical spine disorders included spondylosis, cervical disc disorders (including with radiculopathy or myelopathy), fractures and distortions of the cervical spine, and cervicalgia; potential vascular cervical disorders included aneurysm and dissection of the internal carotid or vertebral arteries, cerebral infarction, and transitory cerebral ischemia not otherwise specified.
“Although these outcomes are rare in the general population, our message to practicing specialists in neurology, psychiatry, and movement disorders, is to be aware of these severe outcomes in this patient population,” said lead author Josef Isung, MD, PhD, of the division of psychiatry in the department of clinical neuroscience at the Karolinska Institute in Stockholm, Sweden. “Close monitoring of individuals at risk, especially those with known severe head- and neck-jerking tics, are warranted to facilitate early specialized interventions when necessary.”
Some of these patients may require interventions beyond standard behavioral modification, including botulinum toxin injections or deep brain stimulation, Dr. Isung said.
Dr. Isung and colleagues analyzed data from the Swedish National Patient Register, the Total Population Register, and the Cause of Death Register. Those with a record of TS/CTD diagnosed in specialist settings were matched on age, sex, and county of birth with 10 unexposed individuals randomly selected from the general population.
The primary outcome was a record of cervical vascular disorders (aneurysm, cerebral infarction, transitory cerebral ischemia) and cervical nonvascular disorders (spondylosis, cervical disc disorders, fractures of the cervical spine, cervicalgia) and cervical surgeries. The final analysis adjusted for other known causes of cervical spine injury—rheumatic disorders, traffic injuries, fall- or sport-related injuries, and attention-deficit/hyperactivity disorder comorbidity.
Dr. Isung and colleagues identified a total of 6,791 individuals with TS/CTD who were age- and sex-matched with 67,910 unexposed individuals. The patients with TS/CTD had a 39 percent increased risk of any cervical spine disorder compared with the unexposed matched cohort. Those with TS/CTD were over one-and-a-half times more likely to experience a vascular cervical disorder and 1.38 times as likely to have a nonvascular cervical disorder. Risks were similar among men and women.
Dr. Isung told Neurology Today that he and colleagues were motivated to study this association because of case reports from colleagues around the world describing very severe neck events such as cervical spine fractures, nerve involvement with limb paralysis, and even cerebrovascular lesions among patients with TS/CTD. “Using Swedish registers, we had a unique opportunity to assess the prevalence and nature of these types of outcomes nationwide, and thus have a better description of how common this association might be,” he said. “By using Swedish registers, we also had the opportunity to control for important covariates that also are known to be associated with cervical spine disorders.”
In the JAMA Neurology paper, Dr. Isung and colleagues noted that vascular cervical spine disorders, while very rare (identified in less than 1 percent of the TS/CTD cohort), can be especially serious; in particular, cerebral arterial dissection with ischemic stroke in children is potentially fatal. A 2001 review in the journal Neurology found 21 percent of children died following dissection of the cerebral artery with a resulting ischemic stroke, and only 37 percent of the survivors experienced a full recovery.
“Physicians working in pediatric neurology settings should be aware that severe neck tics could be a risk factor for such medical complications,” they wrote.
Experts who reviewed the report for Neurology Today agreed the use of a large population-based registry and adjustment for covariates lends the findings statistical strength and supports the need for clinicians to be alert to cervical spine disorders in this population.
“The study is methodologically rigorous and is the only type of study that can be performed to answer this particular clinical question,” said Tamara M. Pringsheim, MD, FAAN, professor of neurology in the department of clinical neurosciences, psychiatry, pediatrics and community health sciences at the University of Calgary.
“The Swedish population-based registries allow researchers to study uncommon disorders and outcomes and make comparisons to matched individuals from the general population. There is also appropriate statistical adjustment for covariates which may be associated with cervical spine disorders.”
Dr. Pringsheim said psychoeducation— a behavioral approach that focuses on making the person aware of when and how their tics occur and then developing behaviors to offset the tic or reverse it (habit reversal)—should include counseling about the possible dangerous consequences of frequent and forceful neck tics. “While these outcomes are uncommon, patients experiencing neck discomfort due to repetitive tics should proactively discuss potential management strategies with their physician,” she said.
Katie Kompoliti, MD, FAAN, professor of neurology at Rush Medical Center in Chicago, said there is a wide range of presentations among patients with tic disorders and that even those with relatively mild tics or involuntary movements can benefit from education and behavioral modification. The latter includes training to create “competitive responses”—the activation of alternative muscle movements that can be less obvious or more socially appropriate and that offset the involuntary tics.
“In our clinic we treat a lot of patients who don't necessarily need medication, but we offer behavior modification training for everyone,” she said. “The training is designed to help patients understand what it takes to learn how to control a body that doesn't want to obey them.”
“Tics are fairly common and there are a lot of tics you can treat conservatively,” Dr. Kompoliti said. “But there are certain movements, especially the whiplash movements—which are not rare—that you can't ignore and need more intensive treatment including medication, because they can cause a lot of morbidity. That's the real message of this new report.”
Dr. Pringsheim said targeted treatments for neck tics such as the Comprehensive Behavioural Intervention for Tics (CBIT)—which trains patients to be more aware of tics and urges to tic, as well as trains them to do another behavior when they feel the urge to tic—and botulinum toxin injections can be very helpful in minimizing tics in the neck area if they are very forceful and frequent.
“Neck pain and discomfort is a frequent complaint from both children and adults with tics affecting the cervical spine,” she said. “I have seen a few adolescent and adult patients who developed a cervical radiculopathy or cervical myelopathy as a consequence of severe tics affecting the neck region. I routinely use both habit reversal therapy (a component of CBIT) and botulinum toxin injections specifically for painful neck tics, which works very well in decreasing both the frequency and intensity of neck movements.”
Drs. Isung, Pringsheim, and Kompoliti had no disclosures.