Posts Tagged ‘ADHD’

SS39069

By Alan Mozes

People with attention-deficit/hyperactivity disorder (ADHD) may be more than twice as likely to develop an early onset form of Parkinson’s, new research warns.

What’s more, among “those ADHD patients who had a record of being treated with amphetamine-like drugs — especially Ritalin [methylphenidate] — the risk dramatically increased, to between eight- to nine-fold,” said senior study author Glen Hanson.

But his team did not prove that ADHD or its medications actually caused Parkinson’s risk to rise, and one ADHD expert noted that the absolute risk of developing Parkinson’s remains very small.

For the study, researchers analyzed nearly 200,000 Utah residents. All had been born between 1950 and 1992, with Parkinson’s onset tracked up until the age of 60.

Prior to any Parkinson’s diagnosis, roughly 32,000 had been diagnosed with ADHD.

Hanson, a professor of pharmacology and toxicology at the University of Utah, said that ADHD patients were found to be “2.4 times more likely to develop Parkinson’s disease-like disorders prior to the age of 50 to 60 years,” compared with those with no history of ADHD. That finding held up even after accounting for a number of influential factors, including smoking, drug and alcohol abuse, and other psychiatric disorders.

“Although we cannot accurately say how much time elapsed between ADHD and [a] Parkinson’s-like disorder diagnosis, it was probably between 20 to 50 years,” he said.

As to what might explain the link, Hanson said that both ADHD and most forms of Parkinson’s source back to a “functional disorder of central nervous system dopamine pathways.”

In addition, Hanson said that “the drugs used to treat ADHD apparently work because of their profound effects on the activity of these dopamine pathways.” Theoretically, the treatment itself might trigger a metabolic disturbance, promoting dopamine pathway degeneration and, ultimately, Parkinson’s, he explained.

Still, Hanson pointed out that, for now, “we are not able to determine if the increased risk associated with stimulant use is due to the presence of the drug or the severity of the ADHD,” given that those treated with ADHD drugs tend to have more severe forms of the disorder.

And while demonstrating “a very strong association” between ADHD and Parkinson’s risk, the findings are preliminary, the study authors added.

Also, the absolute risk of developing Parkinson’s remained low, even in the most pessimistic scenario.

For example, the findings suggest that the risk of developing early onset Parkinson’s before the age of 50 would be eight or nine people out of every 100,000 with ADHD. This compares with one or two out of every 100,000 among those with no history of ADHD, the researchers said.

But the scientists noted that the results should raise eyebrows, because Parkinson’s primarily strikes people over the age of 60. Given the age range of those tracked so far in the study, Hanson said that his team was not yet able to ascertain Parkinson’s risk among ADHD patients after the age of 60.

Hanson also pointed out that because ADHD was only first diagnosed in the 1960s, only about 1.5 percent of the people in the study had an ADHD diagnosis, despite current estimates that peg ADHD prevalence at 10 percent. That suggests that the current findings may underestimate the scope of the problem.

“Clearly, there are some critical questions left to be answered concerning what is the full impact of this increased risk,” Hanson said.

Dr. Andrew Adesman is chief of developmental and behavioral pediatrics at Cohen Children’s Medical Center of New York with Northwell Health in New York City. He was not involved with the study and said the findings “surprised” him.

But, “we need to keep in mind that this study needs to be replicated and that the incidence of these conditions was very low, even among those with ADHD,” Adesman said. “The reality is that this would not affect 99.99 percent of individuals with ADHD.”

Meanwhile, Adesman said, “given that this study needs to be replicated, given that it is unclear whether ADHD medications further increase the risks of Parkinson’s, and given the very low risk in an absolute sense, I believe individuals with ADHD should not be hesitant to pursue or continue medical treatment for their ADHD.”

The report was published online Sept. 12 in the journal Neuropsychopharmacology.

Glen Hanson, DDS, Ph.D., vice dean and professor, pharmacology, School of Dentistry, University of Utah, Salt Lake City; Andrew Adesman, M.D., chief, developmental and behavioral pediatrics, Steven & Alexandra Cohen Children’s Medical Center of New York, Northwell Health, New York City; Sept. 12, 2018, Neuropsychopharmacology, online

https://consumer.healthday.com/cognitive-health-information-26/parkinson-s-news-526/adhd-tied-to-raised-risk-of-early-parkinson-s-737637.html

Advertisements

A new study shows the death of newborn brain cells may be linked to a genetic risk factor for five major psychiatric diseases, and at the same time shows a compound currently being developed for use in humans may have therapeutic value for these diseases by preventing the cells from dying.

In 2013, the largest genetic study of psychiatric illness to date implicated mutations in the gene called CACNA1C as a risk factor in five major forms of neuropsychiatric disease — schizophrenia, major depression, bipolar disorder, autism, and attention deficit hyperactivity disorder (ADHD). All the conditions also share the common clinical feature of high anxiety. By recognizing an overlap between several lines of research, scientists at the University of Iowa and Weill Cornell Medicine of Cornell University have now discovered a new and unexpected role for CACNA1C that may explain its association with these neuropsychiatric diseases and provide a new therapeutic target.

The new study, recently published in eNeuro, shows that loss of the CACNA1C gene from the forebrain of mice results in decreased survival of newborn neurons in the hippocampus, one of only two regions in the adult brain where new neurons are continually produced – a process known as neurogenesis. Death of these hippocampal neurons has been linked to a number of psychiatric conditions, including schizophrenia, depression, and anxiety.

“We have identified a new function for one of the most important genes in psychiatric illness,” says Andrew Pieper, MD, PhD, co-senior author of the study, professor of psychiatry at the UI Carver College of Medicine and a member of the Pappajohn Biomedical Institute at the UI. “It mediates survival of newborn neurons in the hippocampus, part of the brain that is important in learning and memory, mood and anxiety.”

Moreover, the scientists were able to restore normal neurogenesis in mice lacking the CACNA1C gene using a neuroprotective compound called P7C3-A20, which Pieper’s group discovered and which is currently under development as a potential therapy for neurodegenerative diseases. The finding suggests that the P7C3 compounds may also be of interest as potential therapies for these neuropsychiatric conditions, which affect millions of people worldwide and which often are difficult to treat.

Pieper’s co-lead author, Anjali Rajadhyaksha, associate professor of neuroscience in Pediatrics and the Feil Family Brain and Mind Research Institute at Weill Cornell Medicine and director of the Weill Cornell Autism Research Program, studies the role of the Cav1.2 calcium channel encoded by the CACNA1C gene in reward pathways affected in various neuropsychiatric disorders.

“Genetic risk factors that can disrupt the development and function of brain circuits are believed to contribute to multiple neuropsychiatric disorders. Adult newborn neurons may serve a role in fine-tuning rewarding and environmental experiences, including social cognition, which are disrupted in disorders such as schizophrenia and autism spectrum disorders,” Rajadhyaksha says. “The findings of this study provide a direct link between the CACNA1C risk gene and a key cellular deficit, providing a clue into the potential neurobiological basis of CACNA1C-linked disease symptoms.”

Several years ago, Rajadhyaksha and Pieper created genetically altered mice that are missing the CACNA1C gene in the forebrain. The team discovered that the animals have very high anxiety.

“That was an exciting finding, because all of the neuropsychiatric diseases in which this gene is implicated are associated with symptoms of anxiety,” says Pieper who also holds appointments in the UI Departments of Neurology, Radiation Oncology, Molecular Physiology and Biophysics, the Holden Comprehensive Cancer Center, and the Iowa City VA Health Care System.

By studying neurogenesis in the mice, the research team has now shown that loss of the CACNA1C gene from the forebrain decreases the survival of newborn neurons in the hippocampus – only about half as many hippocampal neurons survive in mice without the gene compared to normal mice. Loss of CACNA1C also reduces production of BDNF, an important brain growth factor that supports neurogenesis.

The findings suggest that loss of the CACNA1C gene disrupts neurogenesis in the hippocampus by lowering the production of BDNF.

Pieper had previously shown that the “P7C3-class” of neuroprotective compounds bolsters neurogenesis in the hippocampus by protecting newborn neurons from cell death. When the team gave the P7C3-A20 compound to mice lacking the CACNA1C gene, neurogenesis was restored back to normal levels. Notably, the cells were protected despite the fact that BDNF levels remained abnormally low, demonstrating that P7C3-A20 bypasses the BDNF deficit and independently rescues hippocampal neurogenesis.

Pieper indicated the next step would be to determine if the P7C3-A20 compound could also ameliorate the anxiety symptoms in the mice. If that proves to be true, it would strengthen the idea that drugs based on this compound might be helpful in treating patients with major forms of psychiatric disease.

“CACNA1C is probably the most important genetic finding in psychiatry. It probably influences a number of psychiatric disorders, most convincingly, bipolar disorder and schizophrenia,” says Jimmy Potash, MD, professor and DEO of psychiatry at the UI who was not involved in the study. “Understanding how these genetic effects are manifested in the brain is among the most exciting challenges in psychiatric neuroscience right now.”

http://www.news-medical.net/news/20160427/Study-reveals-new-function-for-CACNA1C-gene-in-psychiatric-diseases.aspx

By ALAN SCHWARZ

More than 10,000 American toddlers 2 or 3 years old are being medicated for attention deficit hyperactivity disorder outside established pediatric guidelines, according to data presented on Friday by an official at the Center.

The report, which found that toddlers covered by Medicaid are particularly prone to be put on medication such as Ritalin and Adderall, is among the first efforts to gauge the diagnosis of A.D.H.D. in children below age 4. Doctors at the Georgia Mental Health Forum at the Carter Center in Atlanta, where the data was presented, as well as several outside experts strongly criticized the use of medication in so many children that young.

The American Academy of Pediatrics standard practice guidelines for A.D.H.D. do not even address the diagnosis in children 3 and younger — let alone the use of such stimulant medications, because their safety and effectiveness have barely been explored in that age group. “It’s absolutely shocking, and it shouldn’t be happening,” said Anita Zervigon-Hakes, a children’s mental health consultant to the Carter Center. “People are just feeling around in the dark. We obviously don’t have our act together for little children.”

Dr. Lawrence H. Diller, a behavioral pediatrician in Walnut Creek, Calif., said in a telephone interview: “People prescribing to 2-year-olds are just winging it. It is outside the standard of care, and they should be subject to malpractice if something goes wrong with a kid.”

Friday’s report was the latest to raise concerns about A.D.H.D. diagnoses and medications for American children beyond what many experts consider medically justified. Last year, a nationwide C.D.C. survey found that 11 percent of children ages 4 to 17 have received a diagnosis of the disorder, and that about one in five boys will get one during childhood.

A vast majority are put on medications such as methylphenidate (commonly known as Ritalin) or amphetamines like Adderall, which often calm a child’s hyperactivity and impulsivity but also carry risks for growth suppression, insomnia and hallucinations.

Only Adderall is approved by the Food and Drug Administration for children below age 6. However, because off-label use of methylphenidate in preschool children had produced some encouraging results, the most recent American Academy of Pediatrics guidelines authorized it in 4- and 5-year-olds — but only after formal training for parents and teachers to improve the child’s environment were unsuccessful.

Children below age 4 are not covered in those guidelines because hyperactivity and impulsivity are developmentally appropriate for toddlers, several experts said, and more time is needed to see if a disorder is truly present.

Susanna N. Visser, who oversees the C.D.C.’s research on the disorder, compiled Friday’s report through two sources: Medicaid claims in Georgia and claims by privately insured families nationwide kept by MarketScan, a research firm. Her report did not directly present a total number of toddlers 2 and 3 years old nationwide being medicated for the disorder, however her data suggested a number of at least 10,000 and perhaps many more.

Dr. Visser’s analysis of Georgia Medicaid claims found about one in 225 toddlers being medicated for A.D.H.D., or 760 cases in that state alone. Dr. Visser said that nationwide Medicaid data were not yet available, but Georgia’s rates of the disorder are very typical of the United States as a whole.

“If we applied Georgia’s rate to the number of toddlers on Medicaid nationwide, we would expect at least 10,000 of those to be on A.D.H.D. medication,” Dr. Visser said in an interview. She added that MarketScan data suggested that an additional 4,000 toddlers covered by private insurance were being medicated for the disorder.

Dr. Visser said that effective nonpharmacological treatments, such as teaching parents and day care workers to provide more structured environments for such children, were often ignored. “Families of toddlers with behavioral problems are coming to the doctor’s office for help, and the help they’re getting too often is a prescription for a Class II controlled substance, which has not been established as safe for that young of a child,” Dr. Visser said. “It puts these children and their developing minds at risk, and their health is at risk.”

Very few scientific studies have examined the use of stimulant medications in young children. A prominent 2006 study found that methylphenidate could mollify A.D.H.D.-like symptoms in preschoolers, but only about a dozen 3-year-olds were included in the study, and no 2-year-olds. Most researchers on that study, sponsored by the National Institute of Mental Health, had significant financial ties to pharmaceutical companies that made A.D.H.D. medications.

Some doctors said in interviews on Friday that they understood the use of stimulant medication in 2- and 3-year-olds under rare circumstances.

Keith Conners, a psychologist and professor emeritus at Duke University who since the 1960s has been one of A.D.H.D.’s most prominent figures, said that he had occasionally recommended it when nothing else would calm a toddler who was a harm to himself or others.

Dr. Doris Greenberg, a behavioral pediatrician in Savannah, Ga., who attended Dr. Visser’s presentation, said that methylphenidate can be a last resort for situations that have become so stressful that the family could be destroyed. She cautioned, however, that there should not be 10,000 such cases in the United States a year.

“Some of these kids are having really legitimate problems,” Dr. Greenberg said. “But you also have overwhelmed parents who can’t cope and the doctor prescribes as a knee-jerk reaction. You have children with depression or anxiety who can present the same way, and these medications can just make those problems worse.”

Dr. Visser said she could offer no firm explanation for why she found toddlers covered by Medicaid to be medicated for the disorder far more often than those covered by private insurance.

Dr. Nancy Rappaport, a child psychiatrist and director of school-based programs at Cambridge Health Alliance outside Boston who specializes in underprivileged youth, said that some home environments can lead to behavior often mistaken for A.D.H.D., particularly in the youngest children.

“In acting out and being hard to control, they’re signaling the chaos in their environment,” Dr. Rappaport said. “Of course only some homes are like this — but if you have a family with domestic violence, drug or alcohol abuse, or a parent neglecting a 2-year-old, the kid might look impulsive or aggressive. And the parent might just want a quick fix, and the easiest thing to do is medicate. It’s a travesty.”

http://www.nytimes.com/2014/05/17/us/among-experts-scrutiny-of-attention-disorder-diagnoses-in-2-and-3-year-olds.html?partner=rss&emc=rss&smid=tw-nytimes&_r=1