Preliminary evidence for lowered basal cortisol in a naturalistic sample of methamphetamine polydrug users.
The effects of chronic methamphetamine use on neuroendocrine functioning in humans are largely undocumented. Here we assessed basal plasma oxytocin, arginine vasopressin, and cortisol levels in a naturalistic sample of methamphetamine polydrug users (n = 12) compared with controls matched for age, gender, education, occupation status, and marital status (n = 17). All of the methamphetamine users tested positive for blood methamphetamine and/or its main metabolite, amphetamine. Other drugs of abuse were detected in a small number of methamphetamine users (MDMA [3,4-methylenedioxy-N-methylamphetamine; n = 2], THC [delta-9-tetrahydrocannabinol; n = 2]). Almost half of the methamphetamine users reported using methamphetamine intravenously, and others smoked or ingested the drug. Methamphetamine users had significantly lower basal plasma cortisol (p = .025), but similar basal plasma oxytocin and arginine vasopressin levels compared with controls. Basal plasma oxytocin was positively correlated (p = .011), with basal plasma arginine vasopressin in controls, but not in methamphetamine users. Methamphetamine users reported higher rates of psychiatric symptoms including substance use disorders, impulsivity, and positive, negative, manic, and disorientation symptoms compared with controls. Psychiatric symptoms were not related to neuroendocrine functioning in either group. These results provide preliminary evidence for lowered basal cortisol levels in methamphetamine polydrug users and encourage further research in to the effects of methamphetamine on neuroendocrine functioning in humans using more highly controlled experimental research designs.
School of Psychology, University of Sydney, NSW, Australia. dcarson@stanford.edu
Dean S
DS
Carson
David P
DP
Bosanquet
C Sue
CS
Carter
Hossein
H
Pournajafi-Nazarloo
Alex
A
Blaszczynski
Iain S
IS
McGregor
D000328:Adult; D019969:Amphetamine-Related Disorders / Q000097:blood*; D001127:Arginine Vasopressin / Q000097:blood; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D008297:Male; D008694:Methamphetamine / Q000008:administration & dosage*; D008875:Middle Aged; D010121:Oxytocin / Q000097:blood
D001127:Arginine Vasopressin; D008694:Methamphetamine; D010121:Oxytocin; D006854:Hydrocortisone