It's not that hard to identify attention deficit hyperactivity disorder (ADHD) in a kid who is jumping up and down on the school desk or flying from one activity to another. But ADHD can be harder to pick up in adults, who have figured out ways to cope but are often still struggling to juggle the responsibilities of modern life. That?s because many people still think of ADHD as a childhood disorder, even though the condition will persist into adulthood for about 60 percent of people. According to experts at the Harvard School of Public Health, ADHD affects about 8 million adults in the U.S. And as much as 80 percent of those 8 million don't know they have ADHD and aren't treated. "Most primary care physicians haven't been trained to see it in adults," says Dr. Leonard Adler, director of the Adult ADHD Program at the New York University School of Medicine. "But the impairments from the disorder are clear in terms of their impact on the workplace, the family and society." Below, Adler talks about how to recognize ADHD in adults and explains how treatment can help them better meet the challenges of everyday life. What is ADHD? ADHD is attention deficit hyperactivity disorder, which is a term doctors use to encompass all attention deficit disorders. It's a very common impairing neuro-psychiatric disorder that affects you throughout your life. How is ADHD diagnosed? For a diagnosis of ADHD, you have to be experiencing either inattentive symptoms or hyperactive/impulsive symptoms. You may have both or have the combination of the two, which is the most common. The second thing is that the symptoms must cause trouble. The impairment must occur in at least two settings, be that at school or work, at home or in social settings. The third thing is that symptoms have to begin in childhood, but that doesn't mean that you have to be diagnosed as a child. Many individuals have symptoms that start in childhood, but the social structures created by school and parents have helped to hide the disorder. As people get older, they go from being managed by others to managing themselves or managing others. This can prove to be very difficult for someone who has ADHD. The fourth thing is that the symptoms have to be from ADHD and not another disorder. Why do people think of ADHD as a childhood disorder? One reason may be that the disorder?s criteria uses childhood symptoms and many people don?t think about how the symptoms may change and manifest in adulthood. For example, inattentive symptoms become much more prominent for adults as compared to the hyperactive-impulsive symptoms. Adults know that it's not appropriate to climb on top of a desk and runs around at the office. How do people tend to cope with symptoms at work? Adults have had a lifetime of coping with their symptoms and it's important to look at how they're coping. They may select jobs that allow them to deal with some of their symptoms better. ?For example, if you have a lot of symptoms of restlessness and you may pick a job that allows you to be physically active rather than choosing a nine-to-five, buttoned-down job sitting at a desk all day,? says Adler. People will tend to find jobs that allow them to move from one activity to another. You not only want to look at coping strategies but you want to look at impairment. Impairment can be relative. You may look at an individual with ADHD and say, ?How in the world can this individual have ADHD? They're an executive.? The reality is that they can't function without their executive assistant. They have to be organized by someone to function. This executive may also be working very, very long hours because everything is done at the last minute. That's relative impairment, which can be quite costly to the individual, because there's not a lot of time left for themselves or their family. It can spill over to difficulties in family life. How does ADHD affect other aspects of life? Untreated adults with ADHD are more likely to underperform academically and professional. They're also about twice as likely to smoke cigarettes. If untreated, they're more likely to use substances. ?In terms of the family, they're more likely to be divorced or separated. A number of patients who have come to our center have been in a family crisis,? says Adler. Their spouse will complain that they aren?t listening and aren?t following through on tasks. They may be seen as unreliable. There have been a number of marriages that have been on the verge of divorce before a spouse was diagnosed or treated for ADHD. Do symptoms tend to be different in men and women? Women and girls tend to have more of the inattentive symptoms, which, in part, have led to some of the under-recognition. Historically, if you had disruptive behavior in school or at home, you were more likely to be identified as having ADHD than if you were daydreaming and not attending to the task. This, in part, led to girls not being identified, though they are a little bit more likely to be recognized as having ADHD as adults. If you look at the gender split in childhood and adulthood, it's four boys to every one girl and about two men to every one woman.