Latest ADHD data at odds with 1st study

WASHINGTON — New data from a large federal study have reignited a debate over the effectiveness of long-term drug treatment of children with hyperactivity or attention-deficit disorder, and have drawn accusations that some research-team members sought to play down evidence that medications do little good beyond 24 months.

The study also indicated that long-term use of the drugs can stunt children's growth.

The latest data paint a different picture than the study's positive initial results, reported in 1999.

One principal scientist in the study, psychologist William Pelham, said the obvious interpretation of the data is that the medications are useful in the short term but ineffective over longer periods, but his colleagues had repeatedly sought to explain away evidence that challenged the long-term usefulness of medication. When their explanations failed to hold up, they reached for new ones, Pelham said.

"The stance the group took in the first paper was so strong that the people are embarrassed to say they were wrong and we led the whole field astray," said Pelham, of the University at Buffalo.

He noted the drugs, including Adderall and Concerta, are among the medications most frequently prescribed for U.S. children, adding, "If 5 percent of families in the country are giving a medication to their children and they don't realize it does not have long-term benefits but might have long-term risks, why should they not be told?"

Range of views

The disagreement has produced a range of views among the researchers about how to accurately present the results to the public.

One e-mail noted an academic review of the group's work, the Multimodal Treatment Study of Children with ADHD (MTA), asked why the researchers were "bending over backward" to play down negative implications for drug therapy.

Peter Jensen, one of Pelham's fellow researchers, said Pelham was biased against the use of drugs.

Jensen said Pelham was the only member of the team who took away "the silly message" that the study raised questions about the long-term utility of drugs, but interviews and the e-mails show Pelham was not alone.

The MTA was designed to test whether children diagnosed with attention-deficit hyperactivity disorder, or ADHD, do better when treated with drugs, with drugs plus talk therapy, with talk therapy alone or with routine medical care alone. Children with the disorder have trouble paying attention, are hyperactive and sometimes disruptive in school.

The initial 14-month analysis published in 1999 randomly assigned children to one of four treatment options and showed those treated with medication did much better than those who got only talk therapy or routine care.

Physicians notified

The drugs' manufacturers distributed thousands of reprints of the article to physicians at a time diagnoses of ADHD were spiraling upward. Because children given drugs alone appeared to do about as well as those treated with drugs and talk therapy, the study skewed treatment toward medication.

In a second phase of the study, the researchers followed the children and compared how they fared, but researchers no longer randomly assigned them to the various treatment options, making this phase less scientifically rigorous.

In August 2007, the MTA researchers reported the first follow-up data, which by then no longer showed differences in behavior between children who were medicated and those who were not. However, the data did show that children who took the drugs for 36 months were about an inch shorter and 6 pounds lighter than those who did not.

Favorable light

A news release issued by the National Institute of Mental Health (NIMH) at the time, however, presented the results in a more favorable light. Dated July 20, 2007, the news release was titled "Improvement Following ADHD Treatment Sustained in Most Children."

The news release did note that the initial advantages were no longer evident, but it quoted Jensen as saying this did not mean long-term drug therapy was ineffective.

The Jensen quote said, "We were struck by the remarkable improvement in symptoms and functioning across all treatment groups." Rather than saying the growth of children on medication was stunted, the news release said children who were not on medication "grew somewhat larger."

Number of prescriptions

In 2004, physicians wrote 28.3 million prescriptions for ADHD drugs; last year, they wrote 39.5 million, according to data from IMS Health.

With the MTA having followed the children for eight years, the latest data have confirmed there are zero long-term differences between children who were continuously medicated and those who were never medicated. Some of data were published online Thursday in the Journal of the American Academy of Child and Adolescent Psychiatry.

Jensen denied the researchers misled the public, pointing out that some children getting the drugs did better over the long term. Looking at overall results was not as useful as studying how particular groups of children fared, he said.

Jensen and another co-author, L. Eugene Arnold at The Ohio State University, who are both psychiatrists, emphasized individualizing treatment and warned parents against abruptly terminating drug therapy.

Analysis of subgroup

The subgroup analysis found that children in homes that were economically stable did the same in the long term with or without medication. Children from deprived backgrounds slid backward as soon as the intensive therapy stopped and they went back to their communities. About one-third — those with the least impairment to begin with — continued to improve over the long term.

Jensen and co-author Benedetto Vitiello at the NIMH said drugs may not have shown an overall long-term benefit because the quality of routine care children received may have been inferior to the care they got during the initial part of the study. Jensen said the take-home message was that community care needs improvement.

James Swanson, another MTA co-author and a psychologist at the University of California at Irvine, said he believed the researchers had been open about the diminishing benefits of medication. He cited scientific publications in which he and others reported data showing that medications lost effectiveness over time and stunted growth.

"If you want something for tomorrow, medication is the best, but if you want something three years from now, it does not matter," he said. "If you take medication long-term beyond three years, I don't think there is any evidence that medication is better than no medication."