Cerebral phosphorus metabolite abnormalities in opiate-dependent polydrug abusers in methadone maintenance.
This study evaluated cerebral phosphorus metabolites in opiate-dependent polydrug abusers in methadone maintenance therapy (MMT) and determined whether metabolite profiles differed based on treatment duration. Phosphorus magnetic resonance spectroscopy (31P-MRS) data were acquired with the ISIS volume localization method from a 50-mm thick axial brain slice through the orbitofrontal and occipital cortices. Study subjects included 15 MMT subjects, seven having undergone treatment for an average of 39 +/- 23 weeks (mean +/- S.D.) and eight having undergone treatment for 137 +/- 53 weeks, as well as an age matched comparison group (n = 16). The methadone dose administered on the study day averaged 70.5 +/- 17.1 mg and was statistically equivalent in short- and long-term subgroups. MMT subjects (n = 15) differed from control subjects in percent phosphocreatine (%PCr) levels (-13%), and in both phosphomonoester (%PME, +13%) and phosphodiester (%PDE, +10%) levels, which likely reflect abnormalities in energy and phospholipid metabolism, respectively. There were no sex effects or group by sex interaction effects on these measures. In short-term MMT treatment subjects, abnormal %PCr (-18%), %PME (+20%) and %PDE (+17%) levels were found compared with control subjects. The only metabolite abnormality detected in long-term MMT subjects was decreased %PCr (-9%), in spite of continued illicit drug abuse. From these data, we conclude that polydrug abusers in MMT have 31P-MRS results consistent with abnormal brain metabolism and phospholipid balance. The nearly normal metabolite profile in long-term MMT subjects suggests that prolonged MMT may be associated with improved neurochemistry.
Kaufman
M J
MJ
Brain Imaging Center, McLean Hospital, MA 02478, USA. kaufman@mclean.org
Pollack
M H
MH
Villafuerte
R A
RA
Kukes
T J
TJ
Rose
S L
SL
Mendelson
J H
JH
Cohen
B M
BM
Renshaw
P F
PF
D000328:Adult; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D016022:Case-Control Studies; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008297:Male; D008691:Methadone / Q000627:therapeutic use*; D008875:Middle Aged; D009294:Narcotics / Q000627:therapeutic use*; D009293:Opioid-Related Disorders / Q000378:metabolism* / Q000534:rehabilitation; D010758:Phosphorus / Q000378:metabolism*
D009294:Narcotics; D010758:Phosphorus; D008691:Methadone