Statins are known to control the levels of cholesterol and help reduce several health risks, including heart disease. But a new study has found that statins may increase levels of aggression in women.

Researchers at the San Diego School of Medicine, University of California, conducted their study on a group of 1,000 men and postmenopausal women. During the study, they randomly assigned them to either the group who received statin therapy or the ones who were kept on placebo for 6 months. The statin therapy involved the two popular drugs simvastatin or pravastatin.

After dividing the subjects into two groups, the researchers keep track of who belonged to which group. At the end of 6 months, the researchers noticed that aggressive behavior declined in the men who were given statin therapy but increased in the women on statin therapy.

The researchers measured the level of aggression a week before and after the statin treatment, taking note of testosterone level, quality of sleep and frequency of hostile acts toward themselves and the people and things around them.

In postmenopausal women over 45, a significant difference in aggression was observed. The researchers found that the before and after difference in aggression was more in women “who began with lower aggression at baseline,” reports the Financial Express.

On the other hand, only three men showed a striking increase in aggression when placed on statin therapy. When they were excluded from the analysis of the study results, all of the other men showed a gradual decrease in aggression.

The complete study findings have been published in the journal PLOS ONE.