Prefrontal grey-matter changes in short-term and long-term abstinent methamphetamine abusers

Abstract

Authors explored grey-matter density in 29 methamphetamine abusers and 20 healthy comparison subjects using voxel-based morphometry. Grey-matter density changes and performances on the Wisconsin Card Sorting test (WCST) were also compared between 11 short-term (<6 months) and 18 longterm (o6 months) abstinent methamphetamine abusers. Methamphetamine abusers had lower greymatter density in the right middle frontal cortex (corrected p<0.05) and more total errors in the WCST (p<0.01) relative to healthy comparison subjects. Grey-matter density decrease in the right middle frontal cortex correlated with total errors in the WCST in methamphetamine abusers (r=x0.45). Long-term abstinent abusers had significantly less right middle frontal grey-matter density decrease (p<0.01) and total errors in the WCST (p<0.01) than short-term abstinent abusers, but more than the healthy comparison subjects. We report that methamphetamine abusers have prefrontal grey-matter deficit, which may, in part, recover with long-term abstinence.

An Evaluation of the Evidence that Methamphetamine Abuse Causes Cognitive Decline in Humans

“…In MA-dependent humans, MA intake typically ranges between 0.5 to 1.4 g per day (Hoffman et al, 2006;Kim et al, 2006;King et al, 2010;Simon et al, 2002), with daily intake most likely being restricted by the financial cost of MA and/ or the physiological/psychological consequences of use (eg, hyperactivity, psychosis). Assuming that an average adult weighs B80 kg (Ogden et al, 2004), this equates to an intake of 6-17.5 mg/kg per day, although purity of the source and method of administration can affect the precise amount of MA ingested.…”

“…Of these eight studies (see Table 1), five found that the MA-dependent participants performed worse than the control participants on a subset of the cognitive tests administered (Hoffman et al, 2006;Kim et al, 2006;Rippeth et al, 2004;Salo et al, 2007Salo et al, , 2009. The other three studies did not find significant differences between the groups on multiple cognitive tests (Chang et al, 2005;King et al, 2010;Simon et al, 2010), although two of these studies used Bonferroni correction for statistical significance, and this method may be overly conservative when dependent variables are interrcorrelated (Miller, 1981), as is the case with performance on most cognitive tests (Warner et al, 1987).…”

“…Results showed that participants who were briefly abstinent performed significantly worse on the Stroop Task than participants who were abstinent for at least a year. Kim et al (2006) administered three neuropsychological tests (Wisconsin Card Sorting, Stroop Test, and Trailmaking Test) to MA-dependent participants who were abstinent for a period of less than 6 months, and compared their performance to MA-dependent participants who were abstinent for more than 6 months. The groups did not differ significantly in age, gender, socioeconomic status, education, alcohol use, cigarette smoking, or duration of MA use.…”

Factors Influencing the Use of Methamphetamine by Dental Patients in the United States

“…1,31 Excessive exposure to methamphetamine has also has been linked to chronic health risks such as coronary heart disease, cardiomyopathy, pulmonary edema, stroke, and seizures. 31,32,33 Other effects of methamphetamine use include, dermatological infections, skin ulcerations,…”

Methamphetamine Addiction: A Review of the Literature

“…The main functions altered are learning, episodic memory, executive functions, speed of information treatment, working memory and perceptual narrowing [63]. The cognitive deficits persist over six months after withdrawal [64,65].…”