ADHD Medications Linked to Lower Crime Rates

A large Swedish population study has led to a provocative discovery regarding adults with attention-deficit/hyperactivity disorder (ADHD).

When individuals with that disorder used ADHD medications, their crime rates decreased.

The study was headed by Paul Lichtenstein, Ph.D., of the Karolinska Institute in Stockholm. The results of the study were published in the November 22, 2012, New England Journal of Medicine.

Using Sweden’s linked population-based registers, which include unique personal identification numbers, Lichtenstein and his colleagues gathered information on approximately 26,000 adults with a diagnosis of ADHD, their medical treatment, and any criminal convictions in Sweden they may have had from 2006 to 2009.

Their analysis showed that more than half of the men had taken ADHD medications and that more than one-third had been convicted of at least one crime during the study period. They also found that two-thirds of the women had taken ADHD medications and that 15 percent had been convicted of at least one crime during the study period.

The researchers then focused on those subjects who had used ADHD medications and compared their crime rates while taking ADHD medications with their crime rates while not taking them. Data showed that when the men were taking their ADHD medications, their crime rate dropped by 32 percent. While the women were taking their ADHD medications, their crime rate dropped by 41 percent.

“These findings raise the possibility that the use of medication reduces the risk of criminality among patients with ADHD,” the researchers concluded, adding that “[i]t is possible that pharmacologic ADHD treatment helps patients to better organize their lives or contributes to enduring changes at the neuronal level.”

“Although some experts believe that for many individuals, crime is an ingrained (i.e., trait-like) behavioral pattern not amenable to medication-induced changes in ‘state,’ this study convincingly shows that ADHD treatment reduces the propensity of at least some individuals to commit crimes,” Peter Roy-Byrne, M.D., a professor of psychiatry at the University of Washington, asserted in Journal Watch Psychiatry.

“We have found similar results in our work that shows that treatment for ADHD markedly reduces comorbid disorders,” Joseph Biederman, M.D., a professor of psychiatry at Harvard Medical School and an ADHD expert, told Psychiatric News.

He and his colleagues conducted a 10-year prospective follow-up study of boys with ADHD. They found that those who had received ADHD medications were significantly less likely to subsequently develop anxiety disorders, major depression, conduct disorder, and oppositional defiant disorder compared with those who had the disorder but who had not received such medications. The findings appeared in the July 2009 Pediatrics.

The Lichtenstein study was funded by the Swedish Research Council, the Swedish Council for Working Life and Social Research, the Swedish Prison and Probation Services, the Wellcome Trust, and the U.S. National Institute of Child Health and Human Development. ■