Early Methamphetamine Abstinence: fMRI and Brain Function

This study included two groups of subjects, methamphetamine-dependent and healthy control participants, with the purpose of characterizing brain structure and cognition during the first month of abstinence from methamphetamine. Participants were able to participate in one or both phases of the study. Methamphetamine abusers were held as inpatients and abstained from methamphetamine use during the entirety of the study. Phase I covered the 1st week of abstinence and Phase II covered the next 3-4 weeks of abstinence. Control subjects participated as outpatients at timeframes which corresponded to the assessments taken of methamphetamine users. The following outlines the procedures in more detail. After initial telephone screening, in-person screening and recruitment procedures took place at the UCLA Neuropsychiatric Institute. Each methamphetamine abuser subject entered the study after completing an interview and questionnaires on drug use history, and providing a positive urine test for methamphetamine. The evaluation included a psychiatric diagnostic interview according to the Structured Clinical Inventory for DSM-IV (SCID-IV), a medical history and physical examination, blood tests [including a complete chemistry panel, hepatic panel, and tests for hepatitis-C and HIV]. Urine samples were also taken for drug screening of illicit drugs, and to test for pregnancy (female subjects). The methamphetamine abusers were then admitted to the General Clinical Research Center (CRC) and participated on a residential basis, where they were administered daily questionnaires about drug craving, withdrawal and mood. The current study makes available phenotype and genotype data, and interested investigators may contact the principal investigator regarding potential sharing of fMRI data.]]> Inclusion Criteria: Age and Gender: 21 to 50 years of age, both genders. Handedness: Right-handedness (score >20 on a modified Edinburgh Handedness Test). Exclusion Criteria: Psychiatric disease: Current Axis I diagnosis (according to DSM-IV criteria), except for the diagnosis of methamphetamine dependence (methamphetamine abuser group only) and nicotine dependence (both groups). History of Drug Abuse: Potential participants with current dependence on any drug (other than nicotine, or for the methamphetamine group, methamphetamine) were excluded. Medications: Evidence of taking psychotropic medications (other than methamphetamine for the methamphetamine abuser group and nicotine for both groups) was exclusionary for both groups. CNS Disease: Structural brain abnormalities (e.g., neoplasms, subarachnoid cysts), cerebrovascular disease, infectious disease (e.g., abscess), history of other neurological disease, including stroke or head trauma (defined as loss of consciousness > 30 min or requiring hospitalization). Cardiovascular Disease: Advanced coronary artery disease, endocarditis or other cardiac disease likely to result in cerebral embolism. Pulmonary Disease: Significant obstructive pulmonary disease or tuberculosis. Systemic Disease: Endocrinopathies, renal or hepatic failure, or autoimmune disease involving the CNS. Claustrophobia: Subjects were questioned about possible discomfort with being in an enclosed space (e.g., MRI scanner). Those who reported such problems were excluded. Pregnancy: Pregnancy, possible pregnancy, or failure to indicate the use of reliable birth control precautions. A pregnancy test was administered to each female participant before starting each of the 2 phases of the study. Subjects must have agreed to use an effective form of birth control between participation in Phase I and Phase II of the study. The only acceptable methods of birth control were: 1) oral contraceptive; 2) Depo-Provera injection; 3) intrauterine device; 4) diaphragm with contraceptive jelly; 5) condom with contraceptive jelly, foam, or sponge; 6) tubal ligation or hysterectomy; 7) abstinence from heterosexual intercourse. HIV: Subjects who were HIV-seropositive were excluded because HIV infection and the development of AIDS produces confounding alterations in brain activity that are dependent on the stage of AIDS. We excluded any subject whose body contained a ferromagnetic implanted device that might produce a safety hazard during fMRI. We used as guidelines, the manual, Magnetic Resonance: Bioeffects, Safety, and Patient Management45 supplemented by the current information published on the International MR Safety Web Site: http://kanal.arad.upmc.edu/mrsafety.html. Vision: Colorblindness, which could affect performance on the Stroop Task. Language: Lack of fluency in English was exclusionary because it would interfere with performance of psychological tests and filling out questionnaires used in the study. The consent form, all questionnaires and instructions were administered in English. ]]>