Even in the end, Bruce Vincent was generous.
Vincent, a popular Westminster grocery store owner whose very public struggle with early-onset Alzheimer’s disease sparked an outpouring from strangers across the country, died Sunday. The 51-year-old had donated his brain to researchers at Massachusetts General Hospital.
Vincent spent his final years enrolled in a Mass General study of an especially cruel, inherited from of Alzheimer’s disease that strikes at an early age. Vincent’s mother, grandfather, and great grandfather all died of dementia in their 50s.
The early-onset form is rare, accounting for only about 4 percent of the estimated 5 million Americans with the disease. Still, researchers have been studying Vincent and other families with this inherited trait in the belief it may help them understand, and ultimately tame, a disease that has defied treatments. Full story for BostonGlobe.com subscribers.