NEW YORK (FRONTLINE MEDICAL NEWS) – Researchers studying the executive functioning ability of homeless youth have found that individuals with poor executive function report more alcohol abuse and dependence than do those with higher EF.

The results are from a study of 149 youth aged 18-22 years (53% female) living in shelters in Chicago. Subjects self-reported behaviors in a series of interviews that used three validated measures of executive function.

Higher alcohol use significantly correlated to lower EF across the scoring systems used in the study. On one scoring measure, the Behavioral Recognition Index, youth with lower EF also saw significantly more-frequent marijuana use, higher likelihood of drug use during sex, more lifetime sexual partners, and more binge drinking than did those with higher executive functioning.

Scott J. Hunter, Ph.D. , director of neuropsychology at the University of Chicago, presented the findings at the annual meeting of the American Academy of Child and Adolescent Psychiatry. Dr. Hunter said in an interview that the results help identify low executive functioning as both a likely contributor to risk-taking behavior and a potential target of interventions.

“We believe that the EF may be the primary concern, although the interaction [with drugs and alcohol] is something that we have to take into account,” he said. “One of the biggest issues here is how do you disentangle that executive piece with the use of substances?”

In this cohort, Dr. Hunter said, about 75% of subjects were African American and an additional 25% or so were mixed race or Latino. About half comprised a sexual minority (gay, lesbian, bisexual, or transgender). “Many had been kicked out of their homes,” he said.

Close to 80% of the youth in the study used cannabis regularly, and three-quarters used alcohol. The group with low EF used the greatest level of substances regularly. Admission of unprotected sexual intercourse was highest among the heavier substance users as well, suggesting “a reliance on substances to reduce sensitivity to the risks they were taking,” said Dr. Hunter, also a professor in the departments of psychiatry and behavioral neuroscience, and pediatrics at the university.

He said the study “is providing some support for our hypothesis that the less successful these young people are in their development of EF, particularly around inhibition, the more likely it is they are going to be engaging in risk-taking behaviors that lead to cycles of more challenge” and development of psychopathology.

The researchers are considering an intervention for this population derived from EF interventions for use with adolescents with attention-deficit/hyperactivity disorder. In their current shelter environments, he said, the youth are “already undergoing programs to learn adaptive functioning to be more successful, and we’re thinking of adding an executive component where they tie the decision-making component to what they want as outcomes.”

The prefrontal cortex of the brain, which controls executive function, is not yet fully developed in adolescence, and studies have shown that youth growing up in impoverished environments have decreases or alterations in cortical development ( Front Hum Neurosci. 2012 Aug 17;6:238 ). “What we have to think about is that we’re still at a [developmental] point where this enhancement and myelination is taking place – into the mid-20s, in fact. We may find that [an intervention] can help them better activate that,” Dr. Hunter said.

The lead author on this study was Joshua Piche, a medical student at the University of Chicago.

Dr. Hunter also is collaborating with epidemiologist John Schneider, MD, MPH , of the University of Chicago, in a study of 600 young black men who have sex with men. The researchers are looking at drug-, alcohol-related, and sexual decision-making in that cohort, about a quarter of whom are homeless. The study includes functional magnetic resonance imaging in a subgroup of subjects.

Currently, as many as 2 million U.S. youth are estimated to be living on the streets, in shelters, or in other temporary housing environments.