Chicago ? Emergency room visits for school-age athletes with concussions has skyrocketed in recent years, suggesting the intensity of kids’ sports has increased along with awareness of head injuries.

The findings in a study of national data don’t necessarily mean that concussions are on the rise. However, many children aren’t taken for medical treatment, so the numbers are likely only a snapshot of a much bigger problem, doctors say.

“It definitely is a disturbing trend,” said lead author Dr. Lisa Bakhos, an ER physician in Neptune, N.J.

The study examined concussions in organized youth sports involving ages 8 to 19. ER visits for 14- to 19-year-olds more than tripled, from about 7,000 in 1997 to nearly 22,000 in 2007. Among ages 8 to 13, visits doubled, from 3,800 to almost 8,000.

While awareness has increased, many parents, coaches and players still don’t understand how serious concussions can be, Bakhos said. Many often seem less concerned with the injury than with how soon kids can return to sports.

“They want to know if they can play tomorrow, and you’re just like, ‘No!”‘ she said. “It’s not just as simple as get up, shake it off and you’ll be fine.

“If they’re not treated properly, with rest, then they can have long-term problems,” Bakhos said. Those include learning difficulties, memory problems and chronic headaches.

The study appears in Pediatrics, published online today, along with a report about sports-related concussions from the American Academy of Pediatrics’ sports medicine council.

A concussion means the brain has been jostled. Symptoms aren’t always obvious. There usually is no loss of consciousness. And a concussion doesn’t show up on an imaging scan unless there is bruising or bleeding.

Symptoms can include headache, nausea, dizziness and trouble concentrating, and may last about a week. Sometimes it can take months to recover.

Treatment is mainly rest — both physically and mentally, avoiding activities that require concentration and focus. That may mean reducing schoolwork or staying home. Video games, computer use and TV can worsen symptoms and should be avoided, the academy report says. Some doctors advise against aspirin and similar painkillers right after a head injury because they might raise the risk for brain bleeding.

Above all, anyone with a concussion should not return to sports or other physical exertion until their symptoms have disappeared.