title: Low-dose add-on memantine treatment may improve cognitive performance and self-reported health conditions in opioid-dependent patients undergoing methadone-maintenance-therapy.
abstract: An important interaction between opioid and dopamine systems has been indicated, and using opioids may negatively affect cognitive functioning. Memantine, a medication for Alzheimer's disease, increasingly is being used for several disorders and maybe important for cognitive improvement. Opioid-dependent patients undergoing methadone-maintenance-therapy (MMT) and healthy controls (HCs) were recruited. Patients randomly assigned to the experimental (5 mg/day memantine (MMT+M) or placebo (MMT+P) group: 57 in MMT+M, 77 in MMT+P. Those completed the cognitive tasks at the baseline and after the 12-week treatment were analyzed. Thirty-seven age- and gender-matched HCs, and 42 MMT+P and 39 MMT+M patients were compared. The dropout rates were 49.4% in the MMT+P and 26.3% in the MMT+M. Both patient groups' cognitive performances were significantly worse than that of the HCs. After the treatment, both patient groups showed improved cognitive performance. We also found an interaction between the patient groups and time which indicated that the MMT+M group's post-treatment improvement was better than that of the MMT+P group. Memantine, previously reported as neuroprotective may attenuate chronic opioid-dependence-induced cognitive decline. Using such low dose of memantine as adjuvant treatment for improving cognitive performance in opioid dependents; the dose of memantine might be a worthy topic in future studies.
authors.affiliation: 1] Department of Psychology, Asia University, Taichung, Taiwan [2] Division of Clinical Psychology, Institute of Allied Health Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan [3] Department of Psychiatry, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Yun-Hsuan
authors.initials: YH
authors.lastname: Chang
authors.affiliation: Department of Neurology, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Shiou-Lan
authors.initials: SL
authors.lastname: Chen
authors.affiliation: 1] Department of Psychiatry, National Cheng Kung University Hospital, Tainan, Taiwan [2] Department of Psychiatry, Kaohsiung Veteran's General Hospital, Kaohsiung, Taiwan.
authors.forename: Sheng-Yu
authors.initials: SY
authors.lastname: Lee
authors.affiliation: 1] Department of Psychiatry, College of Medicine, National Cheng Kung University, Tainan, Taiwan [2] Addiction Research Center, College of Medicine, National Cheng Kung University, Tainan, Taiwan [3] Department of Psychiatry, National Cheng Kung University Hospital, Tainan, Taiwan.
authors.forename: Po See
authors.initials: PS
authors.lastname: Chen
authors.affiliation: 1] Department of Psychiatry, College of Medicine, National Cheng Kung University, Tainan, Taiwan [2] Department of Psychiatry, National Cheng Kung University Hospital, Tainan, Taiwan.
authors.forename: Tzu-Yun
authors.initials: TY
authors.lastname: Wang
authors.affiliation: 1] Department of Psychiatry, College of Medicine, National Cheng Kung University, Tainan, Taiwan [2] Department of Psychiatry, National Cheng Kung University Hospital, Tainan, Taiwan [3] Department of Psychiatry, National Cheng Kung University Hospital, Dou-Liou Branch, Yunlin, Taiwan.
authors.forename: I Hui
authors.initials: IH
authors.lastname: Lee
authors.affiliation: 1] Department of Psychiatry, College of Medicine, National Cheng Kung University, Tainan, Taiwan [2] Department of Psychiatry, National Cheng Kung University Hospital, Tainan, Taiwan.
authors.forename: Kao Chin
authors.initials: KC
authors.lastname: Chen
authors.affiliation: 1] Department of Psychiatry, College of Medicine, National Cheng Kung University, Tainan, Taiwan [2] Institute of Behavioral Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan [3] Addiction Research Center, College of Medicine, National Cheng Kung University, Tainan, Taiwan [4] Department of Psychiatry, National Cheng Kung University Hospital, Tainan, Taiwan.
authors.forename: Yen Kuang
authors.initials: YK
authors.lastname: Yang
authors.affiliation: Neuropharmacology Section, Laboratory of Neurobiology, National Institute of Environmental Health Sciences/National Institutes of Health, Research Triangle Park, NC, USA.
authors.forename: Jau-Shyong
authors.initials: JS
authors.lastname: Hong
authors.affiliation: 1] Division of Clinical Psychology, Institute of Allied Health Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan [2] Department of Psychiatry, College of Medicine, National Cheng Kung University, Tainan, Taiwan [3] Institute of Behavioral Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan [4] Department of Psychiatry, National Cheng Kung University Hospital, Tainan, Taiwan [5] Center for Neuropsychiatric Research, National Health Research Institute, Zhunan, Miaoli County, Taiwan.
authors.forename: Ru-Band
authors.initials: RB
authors.lastname: Lu
mesh_terms: D003071:Cognition / Q000187:drug effects*; D016903:Drug Monitoring; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008559:Memantine / Q000008:administration & dosage* / Q000493:pharmacokinetics; D058850:Opiate Substitution Treatment; D009293:Opioid-Related Disorders / Q000188:drug therapy* / Q000523:psychology*; D057566:Self Report; D016896:Treatment Outcome
chemical_list: D008559:Memantine