90% Heroin users who are white, the Washington University School of Medicine in St. Louis reported in JAMA Psychiatry. Researchers also found that 75 percent now live in nonurban areas and that most users in the past decade began at an average of 23 years old compared with 16 the 1960s. The use of heroin — which is cheaper and more readily accessible than prescription drugs — has jumped 80 percent to 669,000 users from 2007 to 2012, said the National Survey on Drug Use and Health. Bloomberg news