I’ve heard that autism and ADHD are related. Is that true?

Autism spectrum disorder and ADHD are related in several ways. ADHD is not on the autism spectrum, but they have some of the same symptoms. And having one of these conditions increases the chances of having the other.

Experts have changed the way they think about how autism and ADHD are related. The fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) said that a person couldn’t have autism and ADHD. But the newest version (DSM-5), published in 2013, allows for a person to be diagnosed with both.

But let me back up a bit and talk about how the symptoms of autism and ADHD can overlap. Here are two examples:

• Trouble paying attention: Kids with autism may struggle with this for several reasons. One is that language difficulties can make it seem like kids aren’t paying attention to directions. But it may be that they just don’t understand the directions.

• Trouble socially: ADHD can affect social skills. This can include avoiding eye contact and getting into other people’s personal space.

Sometimes these overlapping symptoms cause a child to be incorrectly diagnosed. If you’re concerned about a possible misdiagnosis, talk to your child’s doctor. Doctors are used to having these kinds of conversations and can even help you get a second opinion.

Also, having one condition increases the chances of having symptoms of the other. Many developmental issues are like this — they’re likely to occur together. For example, kids with language issues are more likely to have reading disorders.

That’s why you have to consider all aspects of a child’s developmental functioning. This includes language, social skills, attention, behavior, mood, academic skills, social skills, play skills, and motor skills. A neuropsychological evaluation and/or assessment by a health care provider will look at all of these areas.

Autism and ADHD are related genetically, too. A person with autism has a bigger chance of having a close relative with ADHD or another developmental disorder. We need more research to better understand the connection, though.

Because kids with autism and ADHD can have similar signs, some of the ways to help with one can be helpful for the other. For example, kids with both usually benefit from sticking to a routine and knowing what to expect.

But there are big differences in the type of therapy recommended for each. Therapy for autism, like applied behavior analysis, can help with communication skills. It can also help reduce repetitive behaviors, which is one of the hallmarks of autism.

Therapy for ADHD is geared toward improving attention and organization. It’s often paired with ADHD medication. But this medication may not help kids who don’t have ADHD.

I know from working with many families that it would help if each condition were neatly separated from the other. But that isn’t the reality. Learning more about each is a good first step toward understanding the complicated ways they’re related.