When Kian Yazdani was in Grade 1, it was clear something was wrong. He was often upset in the morning, and his teachers reported that he had angry outbursts at school.

Doctors suggested ADHD as the culprit, but Melody Yazdani wasn鈥檛 so sure. Noting that her son had dark circles under his eyes, she started doing her own research.

Eventually she read an article about sleep apnea, and noticed that the signs and symptoms it described seemed familiar.

鈥淲ord for word, I saw that it was Kian,鈥 Yazdani told CTV鈥檚 Your Morning Monday from her home in Vienna, Va.

Although ADHD and sleep apnea may not be commonly thought of as similar conditions, they can be mistaken for each other. Dr. Indra Narang, the director of sleep medicine at the Hospital for Sick Children in Toronto, says sleep apnea can cause children to appear distracted and excitable.

A by Finnish researchers found that approximately 10 per cent of European children between the ages of six and eight have sleep apnea.

鈥淲e do know that sleep apnea鈥檚 quite prevalent in otherwise healthy children,鈥 she said in an interview with CTV鈥檚 Your Morning.

鈥淵our body wakes up and your brain wakes up feeling tired in the morning. It results in what we may call hyperactivity during the day.鈥

Sleep apnea occurs in people who have trouble breathing while asleep. When that happens, the brain may awaken in an attempt to correct the breathing issues.

鈥淚f that happens lots of times a night, that鈥檚 associated with a lot of sleep fragmentation and sleep deprivation,鈥 Narang said.

In Kian Yazdani鈥檚 case, a sleep apnea diagnosis led to surgery to remove his tonsils and adenoids.

鈥淗e came out of that surgery breathing through his nose for the first time in months,鈥 Melody Yazdani said.

鈥淗is behaviour improved drastically. He no longer had tantrums in the morning. He鈥檚 keeping his hands to himself.鈥

Yazdani said parents concerned their children might be suffering from sleep apnea should watch out for common symptoms such as mouth-breathing.

鈥淲alk into your child鈥檚 bedroom at night (and) see if they鈥檙e breathing through their mouth, because if they are, they need to see a specialist,鈥 she said.

Other potential symptoms to watch for, according to Narang, include snoring at night and general hyperactivity during the day.

鈥淒efinitely check in with your pediatrician if you鈥檙e worried about your child鈥檚 breathing during sleep,鈥 Narang said.