Severe concussion symptoms have been linked to a long-term recovery problem called post-concussion syndrome, according to a new study.

Post-concussion syndrome is a complex disorder causing prolonged symptoms including dizziness and headaches.

Researchers followed 179 children and teens diagnosed with a concussion during an initial ER visit. They found that the patients with severe concussion symptoms immediately after injury were three times more likely to suffer from post-concussive syndrome one month later. That’s twenty-two out of the original 179 youth participants.