Steroid users appear more likely to commit crimes involving weapons and fraud, scientists in Sweden report.

Steroids are linked to manic episodes, depression, suicide, psychotic episodes and increased aggression and hostility, occasionally triggering violent behavior, including murder.

Researchers at Uppsala University in Sweden studied the relationship between crime and steroid use in 1,440 Swedish residents tested for the drugs between 1995 and 2001 from clinics, including substance abuse facilities, as well as police and customs stations.

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Of those involved in the study, 241 tested positive, with an average age of about 20.

The research team found those who tested positive for steroid use were roughly twice as likely to have been convicted of a weapons offense and one-and-a-half times as likely to have been convicted of fraud.

When the researchers excluded people from substance abuse facilities from their analysis the connection with armed crime remained, but the link between steroid use and fraud disappeared.

While steroids are linked with outbursts of uncontrolled violence known as "'roid rage," they did not appear to be connected with sexual offenses, violent crimes such as murder, assault and robbery, or crimes against property such as theft.

This investigation instead reveals that steroid use may be linked with premeditated crimes—those involving preparation and advance planning.

One explanation the researchers suggest for the findings is that criminals involved in serious crimes such as armed robbery or the collection of crime-related debts might benefit from the muscularity, heavy build and increase in aggression that comes with steroid use.

The scientists report their findings in the November issue of the Archives of General Psychiatry.

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