This article is more than 5 years old. Information may no longer be current.

Brain circuitry may indicate risk for substance abuse in bipolar disorder

MRI analysis indicated sex-specific associations between gray matter volume and future substance abuse in adolescents with bipolar disorder.

“Comorbid [substance use disorder] in [bipolar disorder] is associated with more severe illness outcomes, including increased impulsivity, more severe mood episodes, cognitive deficits, and an increase in the already high risk of suicide attempts. Despite the importance of understanding this comorbidity, there has been a paucity of study on the neural mechanisms underlying its development,” Elizabeth T.C. Lippard, PhD, of Yale School of Medicine, New Haven, Connecticut, and colleagues wrote.

To explore comorbidity between substance use disorders and mood disorders, researchers assessed 30 adolescents with DSM-IV bipolar disorder and minimal alcohol or substance exposure. Study participants completed MRI scans at baseline and the CRAFFT interview at follow-up, approximately 6 years after baseline.

Participants with bipolar disorder who reported subsequent alcohol and cannabis use exhibited lower gray matter volume in prefrontal, insular and temporopolar cortices at baseline, compared with participants with bipolar disorder without substance use (P < .005).

Carolyn Mazure

Future substance use was associated with lower gray matter volume in the lower dorsolateral prefrontal cortex among males and females.

Lower orbitofrontal and insula gray matter volume was associated with future substance use among females, while lower rostral prefrontal gray matter volume was associated with future use in males.

Future tobacco use was associated with lower gray matter volume in the orbitofrontal, insular and temporopolar cortices.

“Our findings provide further evidence that sex matters in neuroscience research and demonstrate the importance of examining differences between girls and boys, women and men," study researcher Carolyn Mazure, PhD, of Yale School of Medicine, said in a press release. “We don't know what we don't study. And what we don’t know can't be used to help others.” – by Amanda Oldt

Disclosure: The researchers report no relevant financial disclosures.