A new study finds the risk of prescription opioid addiction rose 37 percent among young adults between 2002 and 2014. Past-year heroin use also rose among 18- to 25-year-olds, from 2 percent to 7 percent. Among adults ages 26 to 34, risk of an opioid use disorder more than doubled, from 11 percent to 24 percent, HealthDay reports. Heroin use among this age group rose sixfold, to 12 percent. “The potential development of prescription opioid use disorder among youth and young adults represents an important and growing public health concern,” first author Dr. Silvia Martins of the Columbia University Mailman School of Public Health said in a news release. The study appears in the journal Addictive Behaviors .