Damage to brain from chronic methamphetamine use is greater in adolescents

From University of Utah Health Care News:

Feb 11, 2015 1:28 PM

Meth Damages Adolescent Brains Far More than Those of Adults, Study Finds

Perry F. Renshaw, M.D., Ph.D., M.B.A.

(SALT LAKE CITY)—Adolescents who chronically use methamphetamine suffer greater and more widespread alterations in their brain than adults who chronically abuse the drug–and damage is particularly evident in a part of the brain believed to control the “executive function,” researchers from the University of Utah and South Korea report.

In a study with chronic adolescent and adult meth abusers in South Korea, MRI brain scans showed decreased thickness in the gray matter of younger users’ frontal cortex, the area of the brain believed to direct people’s ability to organize, reason and remember things, known as the executive function. A different type of MRI, diffusion tensor imaging (DTI), indicated alterations to the adolescents’ white matter, meaning possible damage to neurons–the cells that relay information via electrical signals from one part of the brain to another. The gray and white matter of chronic adult meth users showed far less damage than that of the adolescents.

The researchers found the evidence of damage to cortical thickness in the frontal cortex of adolescent users alarming.

“It’s particularly unfortunate that meth appears to damage that part of the brain, which is still developing in young people and is critical for cognitive ability,” says In Kyoon Lyoo, M.D., Ph.D., of Ewha W. University in Seoul, South Korea. “Damage to that part of the brain is especially problematic because adolescents’ ability to control risky behavior is less mature than that of adults. The findings may help explain the severe behavioral issues and relapses that are common in adolescent drug addiction.”

Lyoo is first author on the study, published Feb. 10, 2015, in Molecular Psychiatry online. Perry F. Renshaw, M.D., Ph.D., M.B.A., University of Utah USTAR investigator and professor of psychiatry, is the study’s senior author.The results also indicate that it might take much less meth to cause greater damage in adolescent brains because youths typically use smaller amounts of the drug than adults.

Meth is the one of the most widely abused drugs in Asia, but it’s also a problem in the United States, with the Western region of the country experiencing the highest rates of use. Studies with rodents have shown that meth damages the brains of adult rats more than young ones, but whether that holds true in people has been cause for debate.

In one of the largest studies of its type, Lyoo, Renshaw and their colleagues scanned the brains of 111 South Korean adolescents and 114 adults. Among the younger people, 51 used meth while 60 did not. The adults included 54 meth users and 60 non-users.

“There is a critical period of brain development for specific functions, and it appears that adolescents who abuse methamphetamine are at great risk for derailing that process,” Renshaw says. “I think the results show it is hugely important to keep kids off drugs.”

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Methamphetamine users have triple the risk of getting Parkinson’s disease

Figure retrieved from hindawi.com

From EurekAlerts:

PUBLIC RELEASE DATE:  16-Dec-2014

Meth users face substantially higher risk for getting Parkinson’s disease

(SALT LAKE CITY)–In addition to incurring serious dental problems, memory loss and other physical and mental issues, methamphetamine users are three times more at risk for getting Parkinson’s disease than non-illicit drug users, new research from the University of Utah and Intermountain Healthcare shows.

The researchers also observed that women who use methamphetamine may be nearly five times more likely to get Parkinson’s disease compared to women who don’t use drugs. Although findings suggest the risk in women may be higher than that in men, additional studies are needed to corroborate a gender difference.

“Typically, fewer females use meth than males do,” says Glen R. Hanson, D.D.S., Ph.D., a nationally recognized expert in drug addiction, professor and interim dean of the University of Utah School of Dentistry and professor of pharmacology and toxicology, the study’s senior author. “Even though women are less likely to use it, there appears to be a gender bias toward women in the association between meth use and Parkinson’s.”

Published Dec. 11, 2014, in Drug and Alcohol Dependence, the study looked at more than 40,000 records in the Utah Population Database (UPDB), a unique compilation of genealogical, medical, and government-provided information on Utah families that is managed by the Huntsman Cancer Institute at the University of Utah. Karen Curtin, Ph.D., research assistant professor of medicine at the University and associate director of the UPDB, is the study’s first author. Records from University of Utah Health Care and Intermountain Healthcare also provided unidentified patient data that was essential for getting a statewide perspective on the research.

The study confirms an earlier one that looked at nearly 250,000 California hospital discharge records and found a similar risk for Parkinson’s among meth users. That study, however, did not report risks based on gender and looked only at records of hospital inpatients. Hanson and Curtin’s study included both Utah inpatient and outpatient clinic records, capturing a wider segment of the population.

Parkinson’s disease is a progressive movement disorder, with onset typically at age 60 or older, that affects nerve cells in the brain. Its symptoms include tremor, or shaking, often starting in a hand or fingers; slowed movement, such as walking; rigid muscles; loss of automatic movements-blinking or smiling, for example-and speech changes. There is no cure for Parkinson’s, but medications and surgery can alleviate symptoms. It is estimated that 4 million to 6 million people worldwide have the condition.

Hanson, Curtin and their colleagues examined medical records, dating from 1996 through 2011, separated into three groups: those of nearly 5,000 people whose health records indicated they had used meth (including amphetamines), more than 1,800 records indicating cocaine use, and records of a control group of more than 34,000 people selected at random whose health and other records showed no use of illicit drugs. The control group was matched to the meth and cocaine users according to age and sex. The researchers made sure that the group of meth users did not have a medical history of taking other illicit drugs or abusing alcohol, which might have influenced the risk for Parkinson’s.

Cocaine users, who provided a non-meth illicit drug comparison, were not at increased risk for Parkinson’s. “We feel comfortable that it’s just the meth causing the risk for Parkinson’s, and not other drugs or a combination of meth and other drugs,” Hanson says.

All identifying information was removed from the records, so people counted in the study remained anonymous.

The reason female meth users are more at risk for Parkinson’s is not clear. Symptoms of the disease appeared in both female and male meth users in their 50s or later, indicating that the effects of meth may manifest years after initial use. “Oftentimes, we think about what drugs do in the short term, but we don’t tend to give much thought to long-term consequences,” Hanson says.

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