Overlaps Between Tourette’s Disorder and Obsessive-Compulsive Disorder
Tourette’s Disorder Basics
Tourette’s disorder belongs to a group of conditions in the Diagnostic and Statistical Manual called tic disorders. All tic disorders belong to a larger group of conditions called motor disorders; in turn, all motor disorders belong to a group of conditions called neurodevelopmental disorders. Tic disorders are motor disorders because they involve problems in the body’s motor (movement-related) system. Some people develop relatively simple tics that only produce uncontrolled, repetitive movement in a single muscle or just a few muscles. However, others develop complex tics, which produce elaborate, patterned movements in a larger number of muscles.
An individual with diagnosable Tourette’s disorder has either simple or complex recurring tics that trigger both involuntary body movement and involuntary sound production. Body movements associated with the disorder include simple head jerks, eye blinks, shoulder jerks and facial grimaces, as well as complex actions that include two or more of these tics. Vocal sounds associated with the disorder include simple grunts, snorts, sniffles and throat-clearing sounds, as well as complex vocalizations that involve the spontaneous utterance of individual words or larger word groupings. Some people with Tourette’s disorder strike themselves during involuntary body movements, or swear or otherwise use indecent language during involuntary vocalizations.
Obsessive-Compulsive Disorder Basics
Obsessive-compulsive disorder used to belong to a group of conditions in the Diagnostic and Statistical Manual called anxiety disorders. However, in May 2013, the American Psychiatric Association created a new category of conditions—known as obsessive-compulsive and related disorders—which includes OCD and several other disorders with connections to OCD-like behavior. People with OCD experience repeated, troubling mental fixations called obsessions, as well as repeated behavioral urges known as compulsions. Generally speaking, an affected individual’s compulsions and obsessions correspond to one another, and compulsive behaviors are typically intended to ease the mental strain associated with the presence of specific obsessions. The classic example of OCD is a person obsessed with dirtiness or germs who repeatedly washes his or her hands in order to reduce the strain of this cleanliness-related obsession.
More than half of all people diagnosed with Tourette’s disorder clearly have symptoms associated with obsessive-compulsive disorder, according to a study published in 2008 in the journal Brain and Development. In addition, roughly 30 percent of all Tourette’s disorder patients have enough of these OCD-related symptoms to qualify for an actual OCD diagnosis. While the two conditions don’t literally arise from the same causes, they do have a number of potential contributing factors in common. Examples of these potential common factors include hereditary traits passed on through family bloodlines, exposure to toxins while in the womb, exposure to infectious microorganisms, and exposure to certain psychological influences in the home environment.
Tourette’s disorder symptoms can closely mimic OCD symptoms, according to a report issued in 2012 by the International OCD Foundation. This is true mainly because of the potential similarities between the complex body movements and vocalizations produced by people with Tourette’s and the compulsive behaviors acted out by people with OCD. In some cases, a person with OCD may produce compulsive body movements so similar to the movements associated with Tourette’s disorder that his or her doctor must look for relatively minor, secondary symptoms in order to tell the two conditions apart. In an attempt to fully describe the possible overlaps between Tourette’s disorder and OCD, some mental health professionals refer to a unique condition that they call Tourettic obsessive-compulsive disorder or Tourettic OCD. However, this hybrid condition does not have official standing as a mental disorder.
Despite the statistical and symptom-related overlaps between Tourette’s disorder and OCD, the American Psychiatric Association does not consider the two conditions to be closely connected. As evidence of this fact, Tourette’s disorder was not included in the new obsessive-compulsive and related disorders category in the Diagnostic and Statistical Manual. Conditions that were included in this category include body dysmorphic disorder, hoarding disorder, excoriation (skin-picking) disorder and trichotillomania (hair-pulling disorder).