Drug abuse reduces grey matter in women but not men

Drug abuse has long-term effects on brain volume in women but not in men, a study says.

The researchers found that brain structures involved in reward, learning and executive control showed vast changes in women even after a prolonged period of abstinence from drug use.

"We found that after an average of 13.5 months of abstinence, women who were previously dependent on drugs had significantly less grey matter volume in several brain areas compared to healthy women," said senior study author Jody Tanabe, neuroradiology section chief at University of Colorado.

These brain areas are important for decision making, emotion, reward processing and habit formation.

The team analysed structural brain magnetic resonance imaging (MRI) exams in 127 men and women, including 59 people (28 women and 31 men) who were previously dependent on cocaine, amphetamines and/or methamphetamine.

"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," Dr Tanabe said in a paper published in the journal Radiology.

According to researchers, compared to men, women tend to begin cocaine or amphetamine use at an earlier age and show accelerated escalation of drug use.

They also report more difficulty quitting, and upon seeking treatment, report using larger quantities of these drugs.

"We hope that our results will lead to further investigation into gender differences in substance dependence and thus, more effective treatments," the authors said.