Attention Deficit in Adults: It Rarely Travels Alone
Adults have lived longer than children, and thus have had more time to develop other psychiatric disorders. In children with AD/HD, the existence of a comorbid condition is correlated with greater likelihood that the symptoms will persist into adulthood. As the child moves from adolescence to adulthood, the predominant symptoms of AD/HD tend to shift from external, visible ones to the internal symptoms. There seems to be a decrease in observable symptoms of AD/HD with age. Although a given adult may not meet DSM-IV criteria for full AD/HD any longer, he or she may still experience impairment in certain aspects of life. The individual’s perception of his or her degree of impairment can vary. Depending on occupation or domestic situation, the adult may need to deal with higher-level issues that involve executive function.
There has been increasing awareness that many adults and children with AD/HD may also meet criteria for one or more other psychiatric diagnoses. (Comorbidity means having two or more diagnosable conditions at the same time) There is some evidence that the incidence of comorbidity is somewhat higher in adults than in children. However, many of the studies looking at the issue of comorbidity are difficult to compare. Studies used different criteria for AD/HD and bipolar disorder, and sometimes got their subjects from different populations. For example, one might expect to see more complex types of AD/HD in specialized hospital clinics than one would see in a door-to-door survey or in a primary care physician’s office. Despite the differing criteria across studies, and the lack of large general population studies of adult AD/HD, there still convincing data that several other psychiatric diagnoses are common among adults with AD/HD.
Substance Abuse: (Abuse of or addiction to alcohol or drugs) Adult attention deficit disorder seems to be related to earlier onset of substance abuse, a longer period of active abuse, and a lower rate of recovery. (Wilens, Biederman and Mick, Am J Addict 1998) The risk of substance abuse (in an adolescent prospective study) may be higher if the individual has conduct disorder in addition to the AD/HD. Conduct Disorder is a persistent pattern of violating rules, laws and the rights of others. (Milberger, Biederman, Faraone, Wilens, Chu, Am J Addict 1997) A study by Biederman et al (Am J Psychiatry 1995) suggested found that 52% of adults (versus 27% of controls) with AD/HD met criteria for substance abuse. Other studies have found slightly lower but still significantly elevated rates of abuse and addiction in AD/HD adults. AD/HD by itself increased the chance of substance abuse, but if the AD/HD were combined with another disorder such as Antisocial Personality Disorder, Anxiety, Depression or Bipolar Disorder, the rates increased further. It is possible that adults have the higher rate of substance abuse because their AD/HD might not have been treated when they were children. A recent study in Pediatrics showed that AD/HD children and adolescents treated with stimulant medication were less likely to develop later problems with drugs or alcohol.
Antisocial Personality Disorder: This is a personality style characterized by a tendency to violate the rights of others, to flout societal rules, and to lack remorse for misdeeds. About 18-25% of AD/HD 25-year-olds studied were found to have this disorder. Only 2% of the general population has Antisocial Personality Disorder (ASPD.) Children who have AD/HD accompanied with aggressive destructive tendencies seem to be the ones most likely to develop adult ASPD. AD/HD children lacking those tendencies do not seem to have a greatly increased risk of developing ASPD. The individuals with AD/HD and ASPD may end up in the penal system. An impulsive individual might be more likely to get caught than one who plans his criminal activity more carefully.
Learning Disabilities are present in Adults as well as children. Often they are less evident when an individual leaves school and finds a career that matches his or her strengths and weaknesses. However, some individuals continue to experience the effects of learning disabilities in college and at work. When an individual has a learning disability, he or she may have a vague sense of shame because it seems that he or she is not able to perform certain tasks ash well as others.
Mood disorders: Mood Disorders include Major Depression, Dysthymia (Chronic low-level depression) and Bipolar Disorder (Manic Depressive Disorder.) These are present in many individuals with AD/HD. Usually, depression starts later than the first onset of the AD/HD. There has been some debate about the incidence of Bipolar Disorder in individuals with AD/HD. Some might say that rapid mood shifts and frequent irritability are characteristics of AD/HD. Others diagnose a rapid cycling mood disorder. Recurrent major depression is more common in adults with ADHD than in non-ADHD adults. However, one must also be aware that depression can be a side effect of stimulants and several other medications. Because stimulants have been known to exacerbate depression and mania, one should usually treat the mood disorder before treating the AD/HD.
Diagnosing AD/HD in adults can be quite complicated. In order to meet criteria for the diagnosis, one should have evidence of symptoms dating back to age seven. It may be difficult for some individuals to give an accurate, unbiased history of these early events. Often it is useful to get outside corroboration on childhood behavior. The high incidence of comorbid disorders also complicates the picture. Inattention itself is a fairly non-specific finding. Even when the diagnosis of AD/HD is clear, one must be alert for other disorders. One study found that only 12% of adults referred to their clinic had pure AD/HD without any other major psychiatric diagnoses.