The newspaper, citing the results of a posthumous examination of Boogaard's brain by the Bedford VA Medical Center in Bedford, Mass., said the former Minnesota Wild and New York Rangers tough guy had chronic traumatic encephalopathy.
Closely related to Alzheimer's disease, CTE is believed to be caused by repeated blows to the head and has been diagnosed in more than 20 now-dead former NFL players, many boxers and four hockey players.
In most of the cases, the disease was found to have developed long after the playing days of the athletes, rendering them "unlike themselves" -- and sometimes violent -- in their older years.
The Times reported doctors were shocked at how far the disease had progressed in Boogaard, who was 28 when he died in his Minneapolis condominium of an overdose of prescription painkillers.
The reported said doctors told Boogaard's parents he likely would have descended into middle-age dementia.