How common is pyromania? This is a difficult question because acts of pyromania are included in arson statistics reported by law enforcement agencies. So, to find cases of pyromania, forensic psychiatrists must evaluate arson case reports and examine arsonists who are imprisoned or in psychiatric hospitals.
Psychiatrist Nina Lindberg and her colleagues in Finland reviewed 20 years of medical records and psychiatric evaluations of 600 male arsonists. Most of the arsonists had mental disorders, including personality disorders, psychoses and mental retardation. About 68 percent of them had been drunk when they set their fires. The researchers separated the group into criminal arsonists and pure arsonists (those with no other criminal activity) because true pyromaniacs would likely be pure arsonists. Upon applying the DSM-IV criteria for pyromania, the researchers found that only 12 of the 600 met the criteria. However, nine of that 12 had admitted to being drunk when they set fires (they mentioned that the tension and arousal that they felt before fire-setting was increased by drinking alcohol). Therefore, Lindberg and colleagues concluded that less than 2 percent of arson and fire-setting behavior was actually due to pyromania [source: Lindberg].
In debunking the myth that most serial arsonists are pyromaniacs, psychologist Rebekah Doley reviewed several pyromania studies and reported that true pyromania is actually quite rare (accounting for less than 1 percent to about 4 percent of arsons) [source: Doley].
So, if pyromania is such a rare disorder, how much do we know about its causes?