Tourette Syndrome

Introduction

Tourette syndrome is a neuropsychiatric disorder beginning in childhood, which is characterized by chronic motor and verbal mannerisms with or without other features. Common coexisting challenges include attention deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), anxiety disorders, and other behavioral problems. Tourette syndrome is a relatively common, biologically based determined disorder with a strong genetic predisposition in most cases. It is not a functional disorder, although tics are often exacerbated by stress, disappear (for the most part) in sleep, and are usually suppressible (at least for brief periods). There is a wide spectrum of tics and behavioral symptoms that typically vary over time in a waxing and waning fashion. Although infection can precipitate or exacerbate tics, there is no evidence that Tourette syndrome is caused by a reaction to streptococcal infection, virus, or other autoimmune disorder.

A fundamental understanding of the pathophysiology of Tourette syndrome has been as elusive as the search for any underlying gene or genes. However, recent clinical advances have provided new directions in understanding genetic and basic neurobiologic mechanisms as well as new therapeutic options. Effective treatment is available for most affected individuals; this list no longer includes only medications, all of which have side effects that can limit otherwise effective intervention. Cognitive behavior therapy has been demonstrated to be effective and can also be synergistic with drug approaches. It is important to remember that pharmacologic treatment should be limited to symptoms with significant impact on daily functioning—in other words, when the tics cause pain, interfere with ability to concentrate, disrupt others in the classroom, or are otherwise socially disabling. It is often more important to first address coexisting neuropsychiatric problems such as ADHD, although one must always take into account the possibility that treatment of the comorbidity could further exacerbate the tic disorder.

Brief History

Tourette syndrome was first described in 1489 in a manuscript on witchcraft ( Malleus Maleficarum or Witch’s Hammer ). The book described a priest with motor and vocal mannerisms believed to be the result of witchcraft, possession by the devil or exorcism. It was not until 1885 when George Gilles de la Tourette, at the time a medical student at the Salpetriere Hospital in Paris, described nine bizarre patients with a condition that he called “maladie des tics.” The characteristics included childhood onset, variability over time, and a variety of other symptoms, including phonic tics, premonitory urges, echolalia, and coprolalia. With remarkable foresight, Tourette noted a genetic tendency, but he unfortunately concluded that it was a weakened nervous system due to immorality of prior generations. For many decades, while psychoanalytic theory was the predominant treatment approach, Tourette syndrome was explained by severe, repressed childhood conflicts and difficulty with “ego synthesis” because of overprotective parents or repressed masturbatory thoughts. It was not until the 1960s when treatment with first-generation neuroleptics proved to be effective in controlling tics that there was a shift to a more brain-based conceptualization of this disorder. Since then, there has been a veritable explosion in research, and Tourette syndrome is now understood as a heterogeneous neurodevelopmental disorder with strong genetic determinants.

Clinical Presentation

Tics are sudden, repetitive, nonrhythmic movements or sounds, which can be further broken down to simple or complex. Simple tics involve a single set of muscles and appear involuntary—motor mannerisms may be rapid like eye blinking and head jerking or slower (i.e., dystonic) like squinting or arm stretching; simple vocal tics include coughing, throat clearing, and sniffing. Complex tics imply more coordinated activity, which can sometimes appear to be intentional, including hopping or bending, repeating words or phrases (echolalia or palilalia), and unintentional vocal cursing (coprolalia) or gestures (copropraxia). In most cases there is a progression starting with simple motor tics followed by simple verbal and then complex motor and complex verbal tics, but there are many exceptions to the rule. Similarly, although 6–8 years is the most common age of onset of tics, some present as early as 2 or 3 years, whereas others present in adolescence. Interestingly, age of onset or initial complexity does not predict prognosis. Students of the natural history of tics have described a peak at approximately 10 years and a tendency to improve during adolescence with one large prospective clinical study finding that only 23% of 16-year-olds still having moderate or severe tics.

Tourette syndrome is the accepted term given to the combination of waxing and waning motor tics plus at least one verbal mannerism beginning in childhood or adolescence over the course of at least 1 year ( Box 4.1 ). Although the layperson’s notion of Tourette syndrome includes coprolalia, it is actually present in a minority of patients. There has been increasing awareness that the disorder is not simply a motor phenomenon (verbal tics being a unique form of motor activity of the speech apparatus) but a response to a frequently ill-defined sensation (“premonitory urge”) or tension that forms the basis of cognitive behavioral therapy for Tourette syndrome. In that study of teens and young adults, more than 90% reported an impulse to tic (“had to do it”) with intensification of premonitory sensations, if prevented from performing a motor tic.