Cerebrospinal fluid monoamine metabolite levels in male arsonists.

Cerebrospinal fluid (CSF) monoamine metabolite levels were studied in 20 arsonists, 20 habitually violent offenders, and ten healthy inpatient volunteers. The arsonists and violent offenders had been in prison an average of six months before the study. Both the raw data and data adjusted by analysis of covariance for group differences in age, height, sex, and season of the lumbar puncture showed significantly lower concentrations of 3-methoxy-4-hydroxyphenylglycol (MHPG) and 5-hydroxyindoleacetic acid (5-HIAA) in the arsonists than in the other groups. The finding remained the same when arsonists with violent suicide attempts were excluded from the analysis. Although CSF concentrations of MHPG or 5-HIAA did not correlate with the severity of repeated fire-setting behavior, low blood glucose nadir in the oral glucose tolerance test (a measure of the tendency toward hypoglycemia) did. These results support the hypothesis that poor impulse control in criminal offenders is associated with low levels of certain CSF monoamine metabolites and with a hypoglycemic tendency.