ADHD & Co-Existing Disorders
As many as 40-60 percent of children with AD/HD have at least one other major disorder. Any disorder can coexist with AD/HD, but certain disorders seem to occur more commonly with AD/HD.
Which conditions most commonly co-exist with AD/HD?
AD/HD may co-exist with one or more disorders. The most common disorders to occur with AD/HD are
(1) Disruptive Behavior Disorders;
(2) Mood Disorders;
(3) Anxiety Disorders;
(4) Tics and Tourette’s Syndrome; and
(5) Learning Disabilities.
Disruptive Behavior Disorders (Oppositional-Defiant Disorder and Conduct Disorder)
About 40 percent of individuals with AD/HD have oppositional defiant disorder (ODD). Among individuals with AD/HD, conduct disorder (CD) is also common, occurring in 25 percent of children, 45-50 percent of adolescents and 20-25 percent of adults. ODD involves a pattern of arguing with multiple adults, losing one’s temper, refusing to follow rules, blaming others, deliberately annoying others, and being angry, resentful, spiteful, and vindictive.
CD is associated with efforts to break rules without getting caught. Such children may be aggressive to people or animals, destroy property, lie or steal things from others, run away, skip school, or break curfews. CD is often described as delinquency and children who have AD/HD and conduct disorder may have lives that are more difficult than those of children with AD/HD alone.
Mood Disorders
Some children, in addition to being hyperactive, impulsive, and/or inattentive, may also seem to always be in a bad mood. They may cry daily, out of the blue, for no reason, and they may frequently be irritable with others for no apparent reason. Both sad, depressive moods and persisting elevated or irritable moods (mania) occur with AD/HD more than would be expected by chance.
Depression
The most careful studies suggest that between 10-30 percent of children with AD/HD, and 47 percent of adults with AD/HD, also have depression. Typically, AD/HD occurs first and depression occurs later.
While all children have bad days where they feel down, depressed children may be down or irritable most days. Children with AD/HD and depression may also withdraw from others, stop doing things they once enjoyed, have trouble sleeping or sleep the day away, lose their appetite, criticize themselves excessively (“I never do anything right!”), and talk about dying (“I wish I were dead”).
Mania/Bipolar Disorder
Up to 20 percent of individuals with AD/HD also may manifest bipolar disorder. This condition involves periods of abnormally elevated mood contrasted by episodes of clinical depression. Adults with mania may have long (days to weeks) episodes of being ridiculously happy, and even believe they have special powers or receive messages from God, the radio, or celebrities. With this expansive mood, they may also talk incessantly and rapidly, go days without sleeping, and engage in tasks that ultimately get them into trouble. In younger people, mania may show up differently. Children may have moods that change very rapidly, seemingly for no reason, be pervasively irritable, exhibit unpremeditated aggression, and sometimes hear voices or see things the rest of us don’t.
Anxiety
Up to 30 percent of children and 25-40 percent of adults with AD/HD will also have an anxiety disorder. Anxiety disorders are often not apparent, and research has shown that half of the children who describe prominent anxiety symptoms are not described by their parents as anxious. Patients with anxiety disorders often worry excessively about a number of things (school, work, etc.), and may feel edgy, stressed out or tired, tense, and have trouble getting restful sleep. A small number of patients may report brief episodes of severe anxiety (panic attacks) which intensify over about 10 minutes with complaints of pounding heart, sweating, shaking, choking, difficulty breathing, nausea or stomach pain, dizziness, and fears of going crazy or dying. These episodes may occur for no reason, and sometimes awaken patients.
Tics and Tourette’s Syndrome
Only about seven percent of those with AD/HD have tics or Tourette’s syndrome, but 60 percent of those with Tourette’s syndrome have AD/HD. Tics (sudden, rapid, recurrent, nonrhythmic movements or vocalizations) or Tourette’s Syndrome (both movements and vocalizations) can occur with AD/HD in two ways. First, mannerisms or movements such as excessive eye blinking or throat clearing often occur between the ages of 10-12 years. These transient tics usually go away gradually over one-to-two years, and are just as likely to happen in AD/HD children as others. Tourette’s is a much rarer, but more severe tic disorder, where patients may make noises (e.g., barking a word or sound) and movements (e.g., repetitive flinching or eye blinking) on an almost daily basis for years.
Tics can also become more noticeable when patients are treated with stimulants or — much less likely — bupropion. While these medicines no longer appear to cause tics, they may unmask or exaggerate tics. Accordingly, sometimes lowering the dose can decrease the tics.
Learning Disabilities
Individuals with AD/HD frequently have difficulty learning in school. Depending on how learning disorders are defined, up to 60 percent of AD/HD children have a co-existing learning disorder. Learning disabled persons may have a specific problem reading or calculating, but they are not less intelligent than their peers are.
Substance Abuse
Recent work suggests that AD/HD youth are at increased risk for very early cigarette use, followed by alcohol and then drug abuse. Cigarette smoking is more common in adolescents with AD/HD, and adults with AD/HD have elevated rates of smoking and report particular difficulty in quitting. AD/HD youth are twice as likely to become addicted to nicotine as non-AD/HD individuals.
Contrary to popular belief, cocaine and stimulant abuse is not more common among AD/HD-individuals previously treated with stimulants: growing up taking stimulant medicines does not lead to substance abuse as these children become teenagers and adults. Indeed, those AD/HD adolescents prescribed stimulant medication are less likely to subsequently use illegal drugs than are those not prescribed medication.