Washington, February 19 : A double-blind, placebo-controlled multi-center study has confirmed that a form of the amino acid carnitine called L-acetyl carnitine (LAC) is a safe alternative to stimulants that are used for the treatment of attention deficit and/or hyperactivity disorder (ADHD) in children who are also suffering from Fragile X Syndrome, the most common hereditary form of mental retardation.
Children with ADHD find it very difficult to maintain social relationships at home and at school. Stimulant medication like Ritalin is often successfully used to treat children with the condition, but while it is effective in children with mental retardation, it also causes side effects such as increased irritability, decreased verbalization and social withdrawal.
It was observed in a previous study that LAC significantly reduced hyperactive behaviour in FXS boys with ADHD who were treated with it for one year without causing adverse side effects.
With an eye on confirming their findings, the same team of researchers conducted the latest study, which has been reported in the American Journal of Medical Genetics Part A.
Rome-based Universita Cattolica researchers M. Giulia Torrioli and Giovanni Neri, who led the project, involved in the study 51 boys between 6 and 12 years old with FXS and ADHD, who were treated in one of eight centres in Italy, France and Spain.
Each patient followed the treatment for 12 months, which involved 500 milligrams of LAC or a placebo given twice daily. Patients were evaluated by an interdisciplinary team of child neuropsychiatrists and psychologists at the start of the study, after one month, six months and 12 months.
The effects of the drug and placebo were evaluated using a set of neuropsychological tests to assess behaviour.
It was observed that patients treated with LAC demonstrated reduced hyperactive behaviour and increased attention, without exhibiting any side effects. The patients treated with the placebo also showed reduced hyperactive behaviour, though not nearly to the extent as the LAC-treated patients.
According to the researchers, the patients treated with LAC also had significantly improved social ability compared to the placebo-treated group. Both groups took intelligence tests, but LAC did not improve overall intellectual functioning.
"We propose that LAC be recommended as a treatment of ADHD in FXS children, since it effectively reduces hyperactive behavior and improves social abilities without adverse side effects," say the authors.
They suggested that the findings might be applicable to autistic children, who also do not easily tolerate stimulants.