MRI reveals how stimulant abuse affects women differently than men

While drug abuse can have a negative impact on both sexes, a newly published study has shown women’s brains might suffer more long-term effects from stimulant abuse than men. Neuroimaging has revealed that women who were previously dependent on stimulants demonstrate changes in brain structures involved with reward, learning and executive control.

“While the women previously dependent on stimulants demonstrated widespread brain differences when compared to their healthy control counterparts, the men demonstrated no significant brain differences,” said senior author Jody Tanabe, MD, professor of radiology, vice chair of research, and neuroradiology section chief at the University of Colorado School of Medicine in Aurora, in a statement.

The findings were published online July 14 in Radiology.

Results were based on 3T MRIs of 127 men and women. Fifty-nine participants (28 women) were previously dependent on cocaine, amphetamines and/or methamphetamine, and their results were compared against a control group of 68 healthy people (28 women). The previously dependent participants had abused stimulants for an average of 15.7 years, though they had abstained for an average of 13.5 months at the time of the study.

A number of differences between formerly dependent men and women were observed. Women with stimulant dependence showed differences in gray matter volume, with smaller neuroanatomic volumes in large regions of the frontal, parietal, temporal, insular and subcortical areas. Men did not demonstrate these differences.

Gray matter volume in the reward center of the brain, the nuclear accumbens, was negatively correlated with the severity of drug use in women, but not men. These gray matter deficits correlated with actual behavioral tendencies, according to Tanabe. “Lower gray matter volumes in women who had been stimulant dependent were associated with more impulsivity, greater behavioral approach to reward, and also more severe drug use,” she said. “In contrast, all men and healthy women did not show such correlations.”

The authors suggested the differences between sexes could signal a greater neuroanatomic endophenotype that makes women more susceptible to stimulant dependence or more vulnerable to resulting morphologic changes.  “We hope that our findings will lead to further investigation into gender differences in substance dependence and, thus, more effective treatments,” said Tanabe.