David Baxter PhD
Late Founder
Short-term, Recreational Ecstasy Use May Damage Memory
by Megan Brooks, Medscape Medical News
July 26, 2012
Use of 3,4-methylinedioxymethamphetamine (MDMA, ecstasy) ? even in small amounts for a relatively short period ? may harm memory, a new study suggests.
Investigators at the University of Cologne in Germany found that new ecstasy users who took 10 or more pills during a period of 1 year experienced a decline in immediate and delayed visual recall after using the club drug.
"Given these specific memory impairments, our findings may raise concerns in regard to MDMA use, even in recreational amounts over a relatively short time period," lead investigator Daniel Wagner, PhD, told Medscape Medical News.
The study was published online July 26 in Addiction.
Results "Meaningful"
Jean M. Bidlack, PhD, of the Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry in New York, who reviewed the study, said the results are "largely confirmatory" of other studies.
"The results are meaningful," she added, "because many variables, such as the use of other drugs of abuse, were taken into account. Deficits in visual memory have been reported previously, but this study accounts for many confounding factors, which makes the conclusion of MDMA use decreasing immediate and delayed visual recall that much stronger," she told Medscape Medical News.
Dr. Wagner noted that the prospective design of the study minimized the methodological limitations of earlier research, in which it was not possible to say whether cognitive impairments seen among ecstasy users were in place before drug use began.
"By measuring the cognitive function of people with no history of ecstasy use and, 1 year later, identifying those who had used ecstasy at least 10 times and remeasuring their performance, we have been able to start isolating the precise cognitive effects of this drug," he said.
The study recruited new MDMA users who were 18 to 35 years old with no current physical disorder and no current or previous history of neurologic or psychiatric disorder. Anyone who had ingested any other illicit psychotropic substances besides cannabis on more than 5 occasions before the day of the first examination were excluded from the study, as were those with a history of alcohol abuse.
A total of 149 participants underwent a battery of neuropsychological tests at baseline; 109 participants were examined again 1 year later. For statistical analyses, the researchers defined 2 groups of participants: those who did not use any other illicit substance (apart from cannabis [and ecstasy]) over the 1-year study period (nonusers; n = 43) and those who used more than 10 ecstasy pills (MDMA users; n = 23).
After 1 year, ecstasy users showed significant deterioration in immediate and delayed recall on a visual paired associates learning task, in which people memorize pairs of words or objects so that the presentation of one triggers the memory of the other.
Hippocampal Dysfunction?
The researchers found that "although pre-existing group differences were ruled out and a comprehensive number of possible confounders were controlled for, the effects of ecstasy on paired associates learning remained significant despite the relatively short time-period (1 year) and the amounts of MDMA used (10 - 60 pills; mean, 32.44)."
"Given that the hippocampus plays a fundamental role in relational memory, the findings of the present study support the hypothesis that the neural basis for the detrimental effects of MDMA on neurocognition appears to be a hippocampal dysfunction," Dr. Wagner and colleagues say.
The lack of evidence of impairment on any other neuropsychological tests is also noteworthy.
"The fact that this study did not find significant changes in other neuropsychological tests strengthens the reported
effect on visual memory," said Dr. Bidlack.
The authors note that this was not an experimental study and therefore a causal relationship between MDMA use and decline in paired associates learning cannot be presumed. They also say they cannot rule out an impure distinction between subacute and long-term effects of cannabis use, given the minimal abstinence period (12 hours before the first exam).
"We also didn't focus on other relevant domains like psychopathology or social problems," Dr. Wagner added.
The study was supported by the German Research Foundation. The authors and Dr. Bidlack have disclosed no relevant financial relationships.
Source: Addiction. Published online July 26, 2012. Abstract
by Megan Brooks, Medscape Medical News
July 26, 2012
Use of 3,4-methylinedioxymethamphetamine (MDMA, ecstasy) ? even in small amounts for a relatively short period ? may harm memory, a new study suggests.
Investigators at the University of Cologne in Germany found that new ecstasy users who took 10 or more pills during a period of 1 year experienced a decline in immediate and delayed visual recall after using the club drug.
"Given these specific memory impairments, our findings may raise concerns in regard to MDMA use, even in recreational amounts over a relatively short time period," lead investigator Daniel Wagner, PhD, told Medscape Medical News.
The study was published online July 26 in Addiction.
Results "Meaningful"
Jean M. Bidlack, PhD, of the Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry in New York, who reviewed the study, said the results are "largely confirmatory" of other studies.
"The results are meaningful," she added, "because many variables, such as the use of other drugs of abuse, were taken into account. Deficits in visual memory have been reported previously, but this study accounts for many confounding factors, which makes the conclusion of MDMA use decreasing immediate and delayed visual recall that much stronger," she told Medscape Medical News.
Dr. Wagner noted that the prospective design of the study minimized the methodological limitations of earlier research, in which it was not possible to say whether cognitive impairments seen among ecstasy users were in place before drug use began.
"By measuring the cognitive function of people with no history of ecstasy use and, 1 year later, identifying those who had used ecstasy at least 10 times and remeasuring their performance, we have been able to start isolating the precise cognitive effects of this drug," he said.
The study recruited new MDMA users who were 18 to 35 years old with no current physical disorder and no current or previous history of neurologic or psychiatric disorder. Anyone who had ingested any other illicit psychotropic substances besides cannabis on more than 5 occasions before the day of the first examination were excluded from the study, as were those with a history of alcohol abuse.
A total of 149 participants underwent a battery of neuropsychological tests at baseline; 109 participants were examined again 1 year later. For statistical analyses, the researchers defined 2 groups of participants: those who did not use any other illicit substance (apart from cannabis [and ecstasy]) over the 1-year study period (nonusers; n = 43) and those who used more than 10 ecstasy pills (MDMA users; n = 23).
After 1 year, ecstasy users showed significant deterioration in immediate and delayed recall on a visual paired associates learning task, in which people memorize pairs of words or objects so that the presentation of one triggers the memory of the other.
Hippocampal Dysfunction?
The researchers found that "although pre-existing group differences were ruled out and a comprehensive number of possible confounders were controlled for, the effects of ecstasy on paired associates learning remained significant despite the relatively short time-period (1 year) and the amounts of MDMA used (10 - 60 pills; mean, 32.44)."
"Given that the hippocampus plays a fundamental role in relational memory, the findings of the present study support the hypothesis that the neural basis for the detrimental effects of MDMA on neurocognition appears to be a hippocampal dysfunction," Dr. Wagner and colleagues say.
The lack of evidence of impairment on any other neuropsychological tests is also noteworthy.
"The fact that this study did not find significant changes in other neuropsychological tests strengthens the reported
effect on visual memory," said Dr. Bidlack.
The authors note that this was not an experimental study and therefore a causal relationship between MDMA use and decline in paired associates learning cannot be presumed. They also say they cannot rule out an impure distinction between subacute and long-term effects of cannabis use, given the minimal abstinence period (12 hours before the first exam).
"We also didn't focus on other relevant domains like psychopathology or social problems," Dr. Wagner added.
The study was supported by the German Research Foundation. The authors and Dr. Bidlack have disclosed no relevant financial relationships.
Source: Addiction. Published online July 26, 2012. Abstract
