hen 83-year-old Helen Long left her North Carolina home without notice last January, her daughter called state police. The police alerted the community using automated road signs and radio and television ads that aired descriptions of Long and her truck and explained that she had dementia. Within six hours, a UPS driver spotted her vehicle, called for help, and Long was returned home unharmed.But not all elders with dementia who go missing are rescued with such efficiency — or at all.North Carolina is one of only six states with a new type of missing persons program called Silver Alert that experts say is urgently needed to address a growing problem.