Over the past decade, the use of drugs for the treatment of ADHD ( Attention Deficit/Hyperactivity Disorder) has increased faster in adults than in children. In the US, about 1/3 of users of these medications are adults. The medications are sometimes used "off label," meaning they are not approved for this use in the treatment of obesity, fatigue related to depression, stroke or traumatic brain injury.

Prior studies have shown that the medications can raise blood pressure in children and adults and can lead to an increase in heart rate. One study in children suggested elevated risks of sudden cardiac death but overall studies have been limited and not consistent. As a result, in this week's JAMA is a large study looking at adults age 25 to 64, their use of the medications under question and outcomes for safety.

The study follows a parallel study that examined risk of serious cardiovascular events associated with taking ADHD medications in children. That study appeared online in The New England Journal of Medicine on Nov. 1. The child study authors found no evidence of an increased risk of serious cardiovascular events with use of these medications.

The researchers compared users of these drugs with nonusers ( there were 440,000 overall in the study and more than 150,000 were on mediation) and found no evidence that the incidence of cardiovascular events was higher in the users of ADHD medications than in the nonusers. End points looked at were risk of heart attack (MI), sudden cardiac death, and stroke.

Second, the researchers compared adults who were using these drugs with past users who had not taken any of these medications in the prior year. Risk while using these medications was similar to risk after discontinuation. Third, the researchers examined risk in subgroups of users — subgroups defined by the specific type of ADHD drug used, by the duration of use, and by other factors such as prior cardiovascular disease or by prior non ADHD psychiatric conditions. Little evidence of increased risk was found in any subgroup.

ADHD in adults can often be missed. It has a significant impact on an individual's ability to perform both at work and socially. Symptoms of ADHD must be present in different settings. The WHO has a short form screening guide as well as a longer guide. Questions are ranked with scores 1-5 from never to very often. Below are a sampling of the questions in the short questionnaire.

1. How often do you have trouble wrapping up the final details of a project, once the challenging parts have been done?
2. How often do you have difficulty getting things in order when you have to do a task that requires organization?
3. How often do you have problems remembering appointments or obligations?
4. When you have a task that requires a lot of thought, how often do you avoid or delay getting started?
5. How often do you fidget or squirm with your hands or feet when you have to sit down for a long time?
6. How often do you feel overly active and compelled to do things, like you were driven by a motor?

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