News

US panel calls for research into effects of Ritalin

Fred Charatan, Florida

A National Institutes of Health consensus panel of experts from North America which met earlier this month has called for urgent clarification of the diagnosis of attention deficit hyperactivity disorder (ADHD) and research into the long term effects of treatment with methylphenidate hydrochloride (Ritalin).

Attention deficit hyperactivity disorder is estimated to affect 3-5% of school age children in the United States, and is the most commonly diagnosed behaviour disorder in childhood. The panel found that there is no consistency in treatment, diagnosis, or follow up for children with the disorder.

Dr David Kupfer, Thomas Detre professor and chairman of the department of psychiatry at the University of Pittsburgh and chairman of the expert panel, pointed out: "These children are subjected to a fragmented treatment system that reaches beyond health care into a wide range of social and educational support services. Its impact on individuals, families, schools, and society is profound, and it demands our immediate attention."

The panel found that the absence of a simple, consistent diagnostic test for the disorder continues to pose validity problems. Studies they reviewed showed that most children are diagnosed by family doctors, who prescribe drug treatment more frequently than paediatricians or psychiatrists.

The use of methylphenidate hydrochloride and amphetamines has increased in recent years, and more than one million children with the disorder are taking psychostimulants.

The expert panel disagreed on the best approach to treating the disorder--medication, behaviour therapy, or a combination of both. Treatment with medication and certain types of behaviour therapy have been shown to improve the behaviour of children with the disorder but the panel found no evidence that treatment improves academic achievement or long term outcomes, and called for more research in these areas.

The panel concluded: "After years of clinical research and experience with ADHD, our knowledge about the cause or causes of ADHD remains speculative. Consequently, we have no strategies for the prevention of ADHD."

The Israel Medical Association and the country's health ministry voiced strong opposition this week to a private member's bill introduced in the Knesset (parliament) that would regulate the treatment of attention deficit hyperactivity disorder with the drug methylphenidate hydrochloride.

The bill has aroused concern among doctors and public health experts who fear it will lead to unprecedented legislative intervention in doctors' professional judgment. About 1% of Israeli children take the drug as compared with about 3% of American youngsters.

"But a much greater fuss has been made here by a minority of parents upset about side effects," said Professor Asher Or-Noy, a paediatrician and expert on child development at the Hebrew University Hadassah School of Medicine and the Jerusalem Centre for Child Development. "There have been some cases of incorrect diagnosis and unnecessary taking of Ritalin, but these don't justify legal interference."

The member of parliament who introduced the bill, Yona Yahav of the Labour Party, insisted that he didn't want to interfere with doctors' professional actions but that he only wanted to make the process of diagnosis and treatment of the disorder--especially in the educational system--more orderly.

STEVEN EDSON/PHOTONICA
3-5% of schoolchildren in the US are diagnosed with attention deficit hyperactivity disorder but there is no consistency of diagnosis