Even though conduct and oppositional defiant disorders usually begin in childhood (median age of onset=11), Kessler said that if you read DSM-IV-TR carefully, it does not say anything about their persistence into adulthood. So the researchers asked about ODD and CD characteristics in adults.
At the request of NIMH, NCS-R researchers also conducted a subsampling, asking questions about pathological gambling, but those data are still unpublished.
According to the commentary by Insel and Fenton (2005), nearly half of all lifetime cases of impulse control disorder have never been treated. The low proportion of cases that ever seek treatment for impulse control disorder could reflect the perceptions, both on the part of the people with the disorders and of society at large, that their problems are less relevant to the mental health care system than to other systems (e.g., social services, education, criminal justice), wrote Wang and colleagues (2005) in the NCS-R article on treatment.
Kessler said it might be part of a broader problem. "There are a lot of people with complicated comorbidities in treatment who say that they are not getting treatment for particular things that are difficulties. Whether that is just their perception or reality, I don't know," he said.
For instance, he noted quite a few people in the population have adult ADHD. "They have depression, they have anxiety, they have drinking problems, they get divorced and they get into car accidents. As a result, a lot of them are in treatment for mental health problems," Kessler said. "We ask, ‘What are you getting treated for?' They say, ‘Well, my depression or my alcohol(Drug information on alcohol)ism.' We ask, ‘Are you getting treated for your attention problems?' and they say no. They don't know about that."
A similar scenario occurs with IED, Kessler said, where individuals with IED enter the treatment system because they are getting divorced, keep losing their jobs, and often are having problems with alcohol and/or depression. "When we ask if they are getting treatment for their anger problems, they say no. They don't know about that."
Having impulse control disorders as comorbidities has clinical significance, according to Kessler. "It turns out that having those comorbidities [ADHD or IED] is pretty strongly correlated to severity and course of other illnesses, so people who have ADHD or IED tend to be more severely depressed and more persistently depressed," Kessler said.
Although stating that he is a researcher and not a clinician, Kessler believes that when clinicians are unaware their patients may have impulse control disorders, it is a problem. "Digging into some of these lesser-considered but important issues might have some implications for treatment planning," he added.