Vol. 8, No. 4, 2002 Page 5
A preliminary study suggests that quick-tempered individuals produce lower than normal levels of endogenous opioids—natural "feel-good" chemicals similar to opium.
In a randomized, crossover study, Stephen Bruehl and colleagues studied 43 patients with chronic low back pain, and 45 pain-free individuals. The researchers used psychological tests to assess the subjects' anger management styles. Each participant then received either a placebo or a drug, naloxone, that blocks opioid receptors.
After receiving the drug or placebo, the subjects were subjected to painful stimuli on their fingers and forearms. Under normal circumstances, individuals given naloxone report an increased sensation of pain.
When quick-tempered subjects received naloxone and then were subjected to painful stimuli, the researchers report, they did not exhibit an increase in acute pain, "which indicates that endogenous opioid production is impaired, so blocking the receptor has no effect." Subjects in the control group responded normally, reporting that they felt increased levels of pain.
The study by Bruehl et al. is the latest in a series of findings linking hostility or quick temper to biological abnormalities. A 1999 study, for instance (see , Crime Times, 1999, Vol. 5, No. 1, Page 4), found an association between hostility and abnormalities in autonomic control of the heart even in young "at-risk" children. Other studies have shown a link between increased hostility and impaired insulin sensitivity.
Neurologist Fleming Bach, however, cautions that Bruehl's findings are preliminary and that responses to an opioid blocker are not a direct measure of levels of endogenous opioids
"Anger and pain sensitivity in chronic low back pain patients and pain-free controls: the role of endogenous opioids," S. Bruehl, J. Burns, O. Chung, P. Ward, and B. Johnson, Pain, Vol. 99, No. 1-2, September 2002, 223. Address: Stephen Bruehl, Department of Anesthesiology, Vanderbilt University School of Medicine, Suite 403-G MAB, 1211 21st Ave. South, Nashville, TN 37232-1557.
"Hot tempers can make life painful," Peggy Peck, United Press International, August 20, 2002.