Background Because of the widespread opinion in the population that the use of androgenic-anabolic steroids (AAS) induce aggressiveness and violent behaviour, in 2002 the Norwegian Ministry of Justice considered suggesting to the Parliament that such use should be made illegal. However, experts disagreed upon whether any such connexion was proven. The Ministry therefore commissioned a systematic review of the scientific evidence from a group of medical doctors with experience in forensic medicine, substance abuse, anti-doping work and health technology assessment.
Search strategy and study selection The bibliographic databases Medline, Embase, PsycLit, Toxline and the databases of INAHTA and the Cochrane collaboration were searched with a combination of terms signifying aggression, violence, criminal behaviour and androgenic-anabolic steroids (Appendix 1). Animal studies and case reports were excluded. Only studies published in English, German or Scandinavian languages were considered. The search was last performed in August 2003.
All studies considered possibly relevant were retrieved and read independently by two group members. The studies finally included were read and discussed by all group members.
Results The literature search identified 1677 articles, 146 of these (listed in Appendix 2) were retrieved in full text. All of these were registered in Medline or Embase, or both.
25 studies fulfilled the inclusion criteria, primary data from some of these studies were reported in more than one article. There were six randomized placebo-controlled studies (13-19), four other controlled studies (20-24) and fifteen observational studies (25-39). Among the latter seven were studies of the general population (25-31), three were of body-builders (32-34), two of unselected criminals from prison populations (35-36), two were of criminal users of AAS (37-38) and one of dead presumed users of AAS (39). Details of the included studies are found in the evidence tables in Appendix 4.
There is good evidence that low doping doses influence the level of aggressiveness only slightly or not at all.
There is no evidence that moderate doping doses (75-200mg AAS daily orally or 50-100mg daily as injection) increase aggressiveness.
No studies have been done with different AAS concurrently or as repeatedly over long periods of time. The doses used in the experimental studies are far lower than doses used as doping. Accordingly, there is no evidence based on experiments of the effect of such regimens or doses.
In the experimental studies using the highest doses there is some evidence that high doses of AAS in some individuals may trigger mania or hypomania, mental states that may include increased aggressiveness.
In the population studies there is a clear association between the use of AAS, aggressiveness and violence (both as perpetrator and as victim). It is not clear whether there is any causal connection. In the subcultures with much use of AAS there is also more use of alcohol and illicit drugs, more high-risk behaviour and more acceptance of violent behaviour.
There exist some case series and a number of case reports describing persons who have used AAS and performed violent acts. However, these publications are purely descriptive and do not give good evidence on causality.
Summing up There is insufficient scientific evidence to decide whether there is a causal link between the use of AAS, aggressiveness and violent behaviour.
On the other hand, the scientific evidence cannot disprove that such a causal link exists, especially after use of high doses of AAS by susceptible individuals.
Keywords: Testosterone Congeners; Violence; Androgens; Androgenic-anabolic steroids.
Copyright ©2004 by The Norwegian Institute of Public Health (NIPH).