Many other conditions result from genetic factors that are similar to TS. Consequently, the vast majority of people with TS (90%) have one or more other conditions as well. These common co-occurring conditions include Attention Deficit Hyperactivity Disorder, Obsessive-Compulsive Disorder and Mood
Disorders among others. The medical term for these associated conditions is comorbidities. Rather than listing several conditions, many people opt for the shorter term, TS+, although this isn’t a diagnostic term.
60% of children with TS also have Attention Deficit Hyperactivity Disorder or ADHD. ADHD is a neurodevelopmental condition that affects both adults and children. It appears in three ways or “types” depending on the particular symptoms. It can appear as an Inattentive Type, Hyperactivity/Impulsive Type or as a combination of the symptoms of inattention, hyperactivity and impulsivity called the Combined Type. Symptoms usually start in childhood, sometimes continuing throughout adulthood, and may vary depending on the type of ADHD and the individual. To be diagnosed with ADHD, symptoms must interfere with a person’s daily functioning or development. While symptoms must be experienced in at least two different places (e.g. home and school, or home and work), symptoms can be mild, or even absent altogether in some circumstances, such as in the doctor’s office or during an enjoyable activity. Having TS and ADHD is associated with a number of difficulties including academic challenges, family conflict, peer rejection, low frustration tolerance and aggression.
Up to 30% of people with a tic disorder also have Obsessive-Compulsive Disorder or OCD. People with TS are even more likely to have OCD than individuals with any other type of tic disorder. Like TS, the condition affects both children and adults. OCD has two primary symptoms: obsessions and compulsions. Obsessions are unwanted thoughts that recur over and over again causing a lot of stress or anxiety and ultimately resulting in attempts to either ignore the thoughts or to make them go away. Examples include fear of disease or fear of dirt and germs. Compulsions are recurring actions, which have the indented purpose of preventing or reducing distress, or preventing a bad situation or event from happening. Examples include checking something over and over or placing things in a particular order. To have OCD, these obsession and or compulsions must take an hour plus of the person’s time each day, cause extreme distress, or interfere with daily functioning in a significant way. It can be hard to tell the difference between a complex tic and a compulsion. Complicated tics tend to happen in response to a feeling of physical tension or a premonitory urge (e.g., a tingling up the spine or a vague feeling of discomfort). In contrast, compulsions usually happen because a person is trying to relieve anxiety. Compulsions also tend to be more elaborate than tics.
Anxiety & Mood Disorders
In addition to TS, some individuals have anxiety and/or mood disorders such as depression or Bipolar Disorder. These conditions may occur together because both have common origins or causes. Alternatively, a person may develop a mood disorder or anxiety due to emotional distress and loss of self-esteem, which can result from living with TS. Anxiety and mood disorder symptoms can be even more challenging than tics and may require specific intervention and treatment. While reduction in tic severity can help with mood disorder symptoms, this is not always sufficient.
Approximately one-third of individuals with TS+ have neurological storms or rage episodes/attacks. A neurological storm is a sudden, out-of-control explosive outburst that is totally out of proportion to the triggering event or environment. It’s different from a temper tantrum because it isn’t goal-directed. Storms are also very different from predatory anger, which refers to psychopathic individuals who get pleasure from inflicting pain on others. The more associated conditions a person has and the more severe their symptoms are, the more likely they are to have storms. Like tics, storms wax and wane in frequency, are more likely to occur when the person is tired or sick, and are unintentional. They may happen multiple times a day, several times a week or less frequently.
As many as 60% of children with TS have problems with sleep. These problems may stem from ticcing, associated conditions like ADHD and depression, medications (including those that may be used to treat TS symptoms) and alterations in brain structures or neurotransmitters due to TS. Common sleep complaints from individuals with TS include difficulty falling asleep, sleep talking, night terrors, poor sleep quality and non-refreshing sleep. Disturbed or insufficient sleep is associated with poor school performance, impaired memory and concentration, greater behavioural or conduct problems, mood disorders and poor quality of life.
Executive functions are a set of mental processes that help people perform activities like planning, organizing, strategizing, paying attention to and remembering details, as well as managing time and space. Several neurological conditions are associated with deficits in executive functions, otherwise known as executive dysfunction, including OCD, ADHD and mood disorders. Executive dysfunction can cause significant challenges such as problems with goal-setting, planning, completing work on time, adjusting behaviour based on feedback, prioritizing, and sustaining effort. Students with executive dysfunction may require accommodations in order to learn best.
Dysfunction in Sensory Integration
Some individuals with TS have sensory integration deficits meaning they are either hyper- or hypo-sensitive to sensory stimuli. This can affect a child’s gross and fine motor development, coordination, balance, as well as visual, perceptual and self-help skills. Individuals who are hypersensitive will overreact to sensory stimuli. For example, a soft touch may cause them to feel pain. In contrast, individuals who are hyposensitive will underreact to sensory stimuli leading them to crave stimulation. For example, while a hypersensitive individual might appear to be a picky eater, a hyposensitive individual may lick or taste inedible objects.
Other conditions and neuropsychological deficits associated with TS may include Autism Spectrum Disorder, substance use disorders, Oppositional Defiance Disorder, learning disabilities, memory deficits, Panic Disorder, social skills deficits, visual-perceptual motor disabilities and epilepsy.