MINNEAPOLIS (AP) — A new study highlights the heightened danger to young athletes who suffer concussions and sustain new head blows before they’ve fully recovered.

The study was published Monday in Pediatrics. It digs into a national database of sudden deaths in young athletes to focus on blunt trauma among players 21 and younger. Previous studies focused on cardiovascular deaths.

Dr. Barry Maron says a key finding is a worrisome number of prep football players who died of head and neck blows after they had already sustained recent concussions. Maron says it comes at a time of growing awareness about “second-impact syndrome.”

The study says trauma deaths among young athletes are relatively uncommon — four times lower than cardiovascular deaths — but they have a devastating effect on families, communities and physicians.

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