If you’re an adult with ADHD, you’re among millions of other grownups who also live with it. Scientists know your genes play a major role in your chances of having it. They also know there’s a strong association between having trauma when you’re a child and then having ADHD in your adulthood. ADHD is a brain development disorder. Trauma, or traumatic stress, is an emotional response to an alarming or painful event. Both can cause ongoing behavior and attention problems. Studies show adults diagnosed with ADHD are more likely than those without ADHD to also have posttraumatic stress disorder, or PTSD. That’s a mood disorder you might develop after a traumatic event. People with PTSD can have ongoing trauma symptoms, or ones that come and go.