From the Guidelines
Tourette Syndrome is most commonly associated with obsessive-compulsive disorder (OCD) and attention-deficit/hyperactivity disorder (ADHD), with approximately 30-50% of individuals with Tourette Syndrome experiencing OCD symptoms and 50-60% having ADHD. The association between Tourette Syndrome and OCD is well-established, with studies suggesting that individuals with Tourette Syndrome are more likely to have co-occurring OCD, particularly those with early-onset Tourette Syndrome 1. The diagnostic criteria for OCD, as outlined in the DSM-5 and ICD-11, emphasize the presence of obsessions and/or compulsions, which are often seen in individuals with Tourette Syndrome 1.
Some key points to consider when evaluating the association between Tourette Syndrome and other disorders include:
- The presence of co-occurring conditions, such as anxiety disorders, depression, learning disabilities, and autism spectrum disorder, which can cause significant functional impairment 1
- The neurobiological basis for these associations, which involves shared abnormalities in the basal ganglia and related circuits, with imbalances in neurotransmitters like dopamine, serotonin, and norepinephrine contributing to both Tourette Syndrome and its comorbid conditions 1
- The importance of addressing both the tics and associated disorders in treatment approaches, often requiring combination therapy that may include behavioral interventions and medications such as alpha-2 adrenergic agonists, stimulants, or selective serotonin reuptake inhibitors 1
The molecular mechanisms underlying the association between Tourette Syndrome and OCD are complex and involve multiple neurotransmitter systems, including serotonin, dopamine, and glutamate 1. While the exact mechanisms are not fully understood, research suggests that alterations in these systems may contribute to the development of OCD symptoms in individuals with Tourette Syndrome.
Overall, the association between Tourette Syndrome and OCD is well-established, and treatment approaches should prioritize addressing both the tics and co-occurring OCD symptoms to improve functional outcomes and quality of life.
From the Research
Tourette Syndrome Co-morbidities
Tourette Syndrome (TS) is often associated with other disorders, including:
- Attention Deficit Hyperactivity Disorder (ADHD) 2, 3, 4, 5, 6
- Obsessive Compulsive Disorder (OCD) 2, 4, 5, 6
- Depression 2, 4
- Personality disorders 4
- Rage-attacks 2
- Anxiety 2, 6
- Conduct disorders 2
- Sleeping disturbances 2
Prevalence of Co-morbidities
The prevalence of co-morbidities in TS is high, with approximately 90% of patients experiencing co-morbid neuropsychiatric disorders 4. ADHD and OCD are the most common co-morbidities, with 35% to 90% of children with TS experiencing ADHD symptoms 3.
Impact of Co-morbidities
The presence of co-morbid ADHD and/or OCD can have a significant impact on the psychosocial, educational, and neuropsychological consequences of TS 2. Additionally, the symptoms of a co-morbid disorder may appear prior to the onset of tics 2, 3.