No abstract

Cognitive impairment in drug-dependent patients receiving methadone (MMP) maintenance treatment has been reported previously. We assessed cognitive functioning after at least 14 days of stable substitution treatment with buprenorphine (BUP) or MMP and after 8 to 10 weeks. We performed a randomized, nonblinded clinical trial in 59 drug-dependent patients receiving either BUP or MMP maintenance treatment and healthy normal controls (n = 24) matched for sex, age, and educational level. Thirteen patients dropped out of the study before the second testing was performed (BUP, n = 22; MMP, n = 24). A neuropsychological test battery was used to measure selective attention, verbal memory, motor/cognitive speed, and cognitive flexibility. In addition, subjective perceived stress was assessed with a questionnaire. Patients in both treatment groups performed equally well in all of the cognitive domains tested. Both BUP and MMP patients showed significantly improved concentration and executive functions after 8 to 10 weeks of stable substitution treatment. The control group achieved better results than the BUP and MMP groups in most cognitive domains, indicating cognitive impairment in the patients. Perceived stress did not show any significant change after 8 to 10 weeks of treatment, and no major differences were detected between the 3 groups. No effects of perceived stress on cognitive function were found. Our results indicate a cognitive impairment in patients receiving maintenance treatment with BUP or MMP compared with healthy controls. Selective attention improved in both patient groups during treatment. We propose that the improvement of attention may facilitate rehabilitation of drug-dependent patients.

Mortality rates in drug-dependent patients in substitution treatment remain a matter of debate. Although several retrospective toxicological or forensic postmortem studies on this issue have been conducted, few prospective studies have addressed this problem. In a nationally representative sample of 2694 opioid dependent patients in substitution treatment either with methadone or buprenorphine at baseline were monitored over a 12-month period (response rate, 91%). A total number of 1629 (60.4%) were still in treatment after 12 months. The overall mortality rate was 1.04%. In total, 28 patients of the initial sample deceased within the 1-year follow-up period. Eleven (0.4%) of these deaths are due to a fatal intoxication. Three patients (0.1%) died of human immunodeficiency virus/acquired immunodeficiency syndrome, and 3 (0.1%) committed suicide. Thirteen of these patients (4 with overdose/polyintoxication) were not in substitution treatment at the time of death. Other reasons included accidents and deaths due to other medical conditions. Only in one case the reason could not be ascertained. The mortality rate was similar in methadone as compared with buprenorphine patients. Taking into account the high comorbidity of opioid dependent patients and the severity of dependence, the mortality rate of approximately 1% confirms that maintenance treatment could be regarded as a fairly safe treatment.

The development of pharmaceutical agents to treat alcohol use disorders has lagged behind that of depression and schizophrenic psychosis and is hampered by an incomplete understanding of the neurobiological background. Pharmacogenetics may improve treatment in the future.

Visual perception has been shown to be altered in Alzheimer disease (AD) patients, and it is associated with decreased cognitive function. Galantamine is an active cholinergic agent, which has been shown to lead to improved cognition in mild to moderate AD patients. This study examined brain activation in a group of mild AD patients after a 3-month open-label treatment with galantamine. The objective was to examine the changes in brain activation due to treatment. There were 2 tasks to visual perception. The first task was a face-matching task to test the activation along the ventral visual pathway, and the second task was a location-matching task to test neuronal function along the dorsal pathway. Brain activation was measured using functional magnetic resonance imaging. There were 5 mild AD patients in the study. There were no differences in the task performance and in the cognitive scores of the Consortium to Establish a Registry for Alzheimer's Disease battery before and after treatment. In the location-matching task, we found a statistically significant decrease in activation along the dorsal visual pathway after galantamine treatment. A previous study found that AD patients had higher activation in the location-matching task compared with healthy controls. There were no differences in activation for the face-matching task after treatment. Our data indicate that treatment with galantamine leads to more efficient visual processing of stimuli or changes the compensatory mechanism in the AD patients. A visual perception task recruiting the dorsal visual system may be useful as a biomarker of treatment effects.