Jones CM, et al. - Researchers conducted a longitudinal analysis of data from the 2008 to 2017 Treatment Episode Data Set in order to assess the trends and associates of methamphetamine use among heroin treatment admissions in the United States. Participants comprised treatment admissions of people aged ≥ 12 years whose primary substance of use is heroin. Each year, an increase in the percentage of primary heroin treatment admissions reporting methamphetamine use was reported; it increased from 2.1% in 2008 to 12.4% in 2017, a relative percentage raise of 490% and an annual percentage change of 23.4%. Males and females and all demographic and geographic groups examined exhibited increases during the study period. In 2017, 47.1% of primary heroin treatment admissions reporting methamphetamine use reported injecting, 46.0% reported smoking, 5.1% reporting snorting and 1.8% reported oral/other as their usual route of methamphetamine use.