ANN ARBOR—Teens should think twice if they believe the negative effects from misusing medication to treat ADHD are short-term. In fact, problems associated with prescription stimulant misuse can last through age 35, according to a new University of Michigan study.
But using medication to treat attention-deficit/hyperactivity disorder as prescribed by doctors does not show long-term negative effects.
However, high school students who use prescription stimulant medication on their own—without a doctor's orders—are less likely to obtain a four-year college degree and more likely to develop a substance use disorder as adults. In contrast, no such effects are seen among those who only use medication as prescribed. The analyses included several controls for possible confounds, including use of alcohol, marijuana and other drugs during adolescence, and high school GPA.
Past studies have examined the increased risk of short-term consequences, such as headaches, sleep problems, substance-related problems and academic difficulties, when teens use someone else's stimulant medication or deviate from their doctor's orders in using their own medication.
The study is believed to be the first national longitudinal study to examine the relationships between medical and nonmedical use of prescription stimulants during adolescence and substance use disorder symptoms and educational attainment (e.g., earning a bachelor's degree) 17 years later, according to lead author Sean Esteban McCabe, a research professor at the U-M Institute for Research on Women and Gender.
Using data from the national Monitoring the Future study—which is funded by the National Institute on Drug Abuse—the sample included 8,300 high school seniors who were followed from adolescence (age 18 between 1976-1996) to adulthood (age 35 between 1993-2013).
Respondents were asked about which prescription drugs were used, alcohol and marijuana consumption, and the highest educational degree earned.
About one in every six high school seniors reported lifetime nonmedical use of prescription stimulants for ADHD. Use of prescription stimulants outside of medical supervision is highly prevalent (43 percent) among teens prescribed these medications, McCabe said.
The study found that nonmedical use of prescription stimulants during adolescence is significantly associated with symptoms of substance use disorder in adulthood, including alcohol, marijuana and other drug use disorders.
In addition, misuse of prescription stimulants during adolescence is highly correlated with a lower likelihood of graduating from a two- or four-year college. Differences were not found in these associations between men and women.
"This study adds to our understanding about the possible long-term consequences of prescription drug misuse during adolescence, showing that stimulant misuse may contribute to reduced educational attainment and increased difficulties with substance use in adulthood," McCabe said. "And, as we have seen with the appropriate use of other prescribed drugs, adolescents who use prescription stimulants only as directed by their doctor do not show these long-term consequences."
McCabe collaborated on the study with Philip Veliz, research assistant professor at the Institute for Research on Women and Gender; Timothy Wilens, psychiatrist and associate professor at the Massachusetts General Hospital and Harvard University; and John Schulenberg, research professor at the U-M Institute for Social Research and professor in the Department of Psychology.
The study, which appears in the Journal of the American Academy of Child & Adolescent Psychiatry, was funded by grants from the National Institute on Drug Abuse (R01DA001411, R01DA016575, R01DA031160 and R01DA036541).