The vast majority of children and teens with Tourette's Syndrome who are seen in clinical settings also have symptoms of other disorders or conditions. Community samples also indicate that the majority of individuals with TS do not have "just TS."
So, what other disorders tend to be associated with or frequently comorbid with TS? The answer depends on whom you ask and whether the research is based on a clinical sample or a community-based sample. That said, the majority of clinical settings report that a significant percentage of individuals who have TS also have:
In actual practice, expect to see many more comorbid conditions depending on whether the student also has ADHD, OCD, or both. Each of those disorders has its own spectrum of associated conditions, so two students with TS may look significantly different in terms of their overall presentation.
In a community-based study of school children that employed direct interviews and standardized rating scales for 1596 children, Kurlan and his colleagues (2002) found that OCD, ADHD, separation anxiety, overanxious disorder, simple phobia, social phobia, agoraphobia, mania, major depression, and oppositional defiant behavior occurred significantly more frequently in the children who had tics compared to their non-tic peers. But are all of these conditions really associated with tics, or is it the case that some of them are just associated with each other? For example, could it be that you don't find oppositional defiant behavior unless there is also ADHD? There is much that we don't know about what is truly associated with TS and what conditions are only present if there is ADHD or OCD in the presence of TS. Additional research is clearly needed to help identify patterns. For now, I continue encourage school personnel to be alert to the presence of other conditions that may significantly impair the student's academic and social-behavioral functioning.