ADHD stands for attention deficit hyperactivity disorder, a condition with symptoms such as inattentiveness, impulsivity, and hyperactivity. The symptoms differ from person to person. ADHD was formerly called ADD, or attention deficit disorder. Both children and adults can have ADHD, but the symptoms always begin in childhood. Adults with ADHD may have trouble managing time, being organized, setting goals and holding down a job.
ADHD is one of the most common childhood disorders and can continue through adolescence and into adulthood. The average age of onset is seven years old. ADHD affects about 4.1 percent of American adults age 18 years and older in a given year. The disorder affects 9.0 percent of American children age 13 to 18 years. Boys are four times more at risk than girls.
Inattention, hyperactivity, and impulsivity are the key behaviors of ADHD. It is normal for all children to be inattentive, hyperactive, or impulsive sometimes, but for children with ADHD, these behaviors are more severe and occur more often. To be diagnosed with the disorder, a child must have symptoms for six or more months and to a degree that is greater than other children of the same age.
ADHD has three subtypes:
A Growing Problem?
Studies show that the number of children being diagnosed with ADHD is increasing, but it is unclear why. Some say that ADHD is a modern problem, pointing to the fact that the number of American children aged 4-17 who have been diagnosed with ADHD increased 42 percent between 2003 and 2011.
"Parents want to know, 'Is there something in the water? Is it something I'm feeding my child or that I did when I was pregnant?'" says Mandi Silverman, PsyD, a clinical psychologist at the ADHD and Disruptive Behavior Disorders Center at the Child Mind Institute. "Our answer is that there's more awareness, more research, and we have more sophisticated assessment tools." In other words, the better doctors understand the disorder, the better they're able to detect it. That means just as many people might have had the condition decades ago as they do today, but they may never have been diagnosed and treated. A recent review of studies concluded that the true rate of ADHD among children is pretty similar throughout Asia, Africa, Australia, Europe, and the Americas.
ADHD in Adults
About four percent of adults also have the disorder. To officially meet the criteria for ADHD as an adult, symptoms must have started by age 12, even if never properly diagnosed in childhood. Those symptoms can change over time, so ADHD in adults rarely looks the way it does in kids. While some young children with the disorder, might have problems sitting still and end up running all over a classroom, adults are much more likely to have trouble focusing and staying organized. About 60 percent of people who had the condition in childhood still have symptoms as adults.
Physicians and researchers concur that ADHD is a neurobiological disorder, and that brains develop. As children mature into adults, either their brains changed or life has compensated for it. For example, someone with ADHD who is thriving as a traveling salesman might suddenly have problems again if he were to take on a desk job.
Causes
Scientists are not sure what causes ADHD, although many studies suggest that genes play a large role. Like many other illnesses, ADHD probably results from a combination of factors. In addition to genetics, researchers are looking at possible environmental factors, and are studying how brain injuries, nutrition, and the social environment might contribute to ADHD.
Children with ADHD who carry a particular version of a certain gene have thinner brain tissue in the areas of the brain associated with attention. This National Institute of Mental Health research showed that the difference was not permanent, however, and as children with this gene grew up, the brain developed to a normal level of thickness. Their ADHD symptoms also improved.
ADHD Can Be Mistaken for Other Problems
Parents and teachers can miss the fact that children with symptoms of inattention have the disorder because they are often quiet and less likely to act out. They may sit quietly, seeming to work, but they are often not paying attention to what they are doing. They may get along well with other children, compared with those with the other subtypes, who tend to have social problems. But children with the inattentive kind of ADHD are not the only ones whose disorders can be missed. For example, adults may think that children with the hyperactive and impulsive subtypes just have emotional or disciplinary problems.
How is ADHD diagnosed in adults?
Like children, adults who suspect they have ADHD should be evaluated by a licensed mental health professional. But the professional may need to consider a wider range of symptoms when assessing adults for ADHD because their symptoms tend to be more varied and possibly not as clear-cut as symptoms seen in children.
To be diagnosed with the condition, an adult must have ADHD symptoms that began in childhood and continued throughout adulthood. Health professionals use certain rating scales to determine if an adult meets the diagnostic criteria for ADHD. The mental health professional also will look at the person's history of childhood behavior and school experiences, and will interview spouses or partners, parents, close friends, and other associates. The person will also undergo a physical exam and various psychological tests.
For some adults, a diagnosis of ADHD can bring a sense of relief. Adults who have had the disorder since childhood, but who have not been diagnosed, may have developed negative feelings about themselves over the years. Receiving a diagnosis allows them to understand the reasons for their problems, and treatment will allow them to deal with their problems more effectively.