Statins, the hugely popular drug class used to manage blood cholesterol levels and reduce the risk of heart disease, is found to lower aggression in men and increase in women.
In the first randomized trial to look at statin effects on behavior, researchers at the University of California, San Diego School of Medicine report that aggressive behavior typically declined among men placed on statins (compared to placebo), but typically increased among women placed on statins.
Lead author Beatrice A. Golomb said that there have been reports of some individuals reproducibly developing irritability or aggression when placed on statins. Yet in contrast to pre-statin lipid-lowering approaches, clinical trials and meta-analyses of statin use (in which most study participants were male) had not shown an overall tendency toward increased violent death.
For postmenopausal women, said the scientists, the typical effect was increased aggression. The effect was significant for postmenopausal women older than age 45. The increase in aggression (compared to placebo) appeared stronger in women who began with lower aggression at baseline. For men, the picture was more complex. Three male participants who took statins (and no one on placebo) displayed very large increases in aggression.
When these were included in analysis, there was no average effect. When these "outliers" were removed from the analysis, a decline in aggressive behavior for male statin users was significant. It was stronger among younger men who tend to be more aggressive, but actually the effect was most evident in less aggressive men, said Golomb.
Examination revealed statin effects on testosterone and sleep contributed to bidirectional effects. The data reprise the finding that statins don't affect all people equally, effects differ in men versus women and younger versus older. Female sex and older age have predicted less favorable effects of statins on a number of other outcomes as well, including survival.
The findings are published in the online issue of PLOS ONE