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<<   作成日時 : 2009/04/02 00:18   >>

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 大規模な連邦研究データから、ADHD注意欠陥多動障害の子どもへの長期薬物療法の有効性に議論がおこり、24ヶ月以上はほとんど効果がないという証拠を研究チームの何人かは軽視しようとしているという告発を引きおこした。
 研究はまた、薬剤の長期使用が子どもの成長を阻害する可能性を示した。
 最新データは1999年の報告のポジティブな初期の結果と非常に異なる様相を示している。
 この研究の主要な科学者の1人である心理学者のWilliam Pelham は、薬剤は短期的には有益だが、長期的に無効であるとしたが、同僚達は治療の長期効果を釈明しようとした。説明に行き詰まると、新たな説明をしようとした。
 ニューヨーク州立大学のPelham は、アデラールとコンサータを含めた薬剤は米国の子どもに最も多く処方されており、米国家族の5%が子どもに薬剤を与えているが、長期的利点がないが長期的リスクの可能性があるとは気がついていない。
 14ヶ月の初期の研究で、薬剤投与群の効果は明らかだった。2007年8月に最初の追跡調査が行われ、子どもの行動への効果には差が無くなっていた。36ヶ月服薬した子どもは服薬しなかった子どもに比べ1インチ低く、6ポンド体重が軽かった。
 2007/07/20のNIMH国立精神衛生研究所による発表は、好意的な観点の結果発表だった。ほとんどの親や医師は研究で薬物療法が長期的に効果ありとわかったと思った。
 2004年に、ADHD治療薬処方で2830万の処方箋が出された。昨年のデータでは、3950万処方が出された。
 MTAが8年間のフォローでの最新データから、治療の有無で子どもの長期的な効果の差はなかった。サブグループ分析では、約1/3の最初から最もわずかな障害のあるグループが長期的な改善を続けていた。
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米FDAがADHD治療薬の副作用を調査/リタリン
http://kurie.at.webry.info/200709/article_44.html
ADHDに対するリタリン長期服用の効果
http://kurie.at.webry.info/200709/article_63.html
ADHDの薬物療法は効果なし
http://kurie.at.webry.info/200711/article_18.html
増加する10代のADHD/注意欠陥多動性障害
http://kurie.at.webry.info/200807/article_51.html
ADHD治療薬による幻覚/リタリン コンサータ
http://kurie.at.webry.info/200901/article_44.html
リタリン依存症 マウスに大量投与で
http://kurie.at.webry.info/200902/article_21.html
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Debate Over Drugs For ADHD Reignites
Long-Term Benefit For Children at Issue
http://www.washingtonpost.com/wp-dyn/content/article/2009/03/26/AR2009032604018.html
By Shankar Vedantam
Washington Post Staff Writer
Friday, March 27, 2009; Page A01

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 members of the research team have 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 very different picture than the study's positive initial results, reported in 1999.

One principal scientist in the study, psychologist William Pelham, said that the most obvious interpretation of the data is that the medications are useful in the short term but ineffective over longer periods but added that 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 State University of New York at Buffalo. Pelham said the drugs, including Adderall and Concerta, are among the medications most frequently prescribed for American 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?"
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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 that an academic review of the group's work, called 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, responded that Pelham was biased against the use of drugs and was substituting his personal opinion for science.

Jensen said Pelham was the only member of the team of researchers who took away "the silly message" that the study raised questions about the long-term utility of drugs, but interviews and e-mails show that 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 restless and hyperactive, and are sometimes disruptive in school.

The initial 14-month analysis published in 1999 randomly assigned children to one of four treatment options and showed clearly that those treated with medication did much better than those who got only talk therapy or routine care. The drugs' manufacturers distributed thousands of reprints of the article to physicians at a time when diagnoses of ADHD were spiraling upward. Because children given drugs alone appeared to do about as well as those treated with both drugs and talk therapy, the study skewed treatment in the direction of 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. But the data did show that children who took the drugs for 36 months were about an inch shorter and six pounds lighter than those who did not.

A news release issued by the National Institute of Mental Health (NIMH) at the time, however, presented the results in a more favorable light. The release, dated July 20, 2007, was titled "Improvement Following ADHD Treatment Sustained in Most Children." The release noted that the initial advantages of drug treatment were no longer evident, but it quoted Jensen as saying this did not mean that long-term drug therapy was ineffective.

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

As the MTA study continued to find smaller and smaller behavioral differences between children who were medicated and those who were not, use of the drugs soared. Pelham said most parents and doctors took away the message that the study had found drug therapy effective over the long run. In 2004, physicians wrote 28.3 million prescriptions for ADHD drugs; last year, they wrote 39.5 million, according to data provided by IMS Health.

With the MTA having followed the children for eight years, the latest data have confirmed that there are no long-term differences between children who were continuously medicated and those who were never medicated. Some of the data were published online yesterday in the Journal of the American Academy of Child and Adolescent Psychiatry.
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In a telephone interview, Jensen denied that the researchers had misled the public, pointing out that some children getting the drugs did do 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 Ohio State University, who are both psychiatrists, emphasized the importance of individualizing treatment -- and warned parents against abruptly terminating drug therapy.

The subgroup analysis found that children in homes that were socially and economically stable did the same in the long term with or without medication. Children from troubled or 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 that children received may have been inferior to the care they got during the initial part of the study. Jensen said the take-home message is that community care needs improvement.

Brooke Molina, also a co-author and a University of Pittsburgh associate professor of psychology and psychiatry, argued in an e-mail that if the researchers wanted to draw attention to subgroups that might be helped by medication over the long run, they also should acknowledge that "long-term treatment with medication may not be efficacious" for others.

In an interview, Molina said the data do not "support that children who stay on medication longer than two years have better outcomes than children who don't." In an e-mail she shared with Pelham, she noted that academic "reviewers thought we were bending over backward (inappropriately) to dismiss the failure to find medication effects at 8 years."

James Swanson, another MTA co-author and a psychologist at the University of California at Irvine, said he believes that the researchers have been open about the diminishing benefits of medication therapy. He cited a variety of 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."

Pelham, who has conducted many drug therapy studies, said the drugs have a valuable role: They buy parents and clinicians time to teach youngsters behavioral strategies to combat inattention and hyperactivity. Over the long term, he said, parents need to rely on those skills.

A yet-to-be-published study, Pelham added, found that 95 percent of parents who were told by clinicians to first try behavioral interventions for ADHD did so. When parents were given a prescription for a drug and then told to enroll their children in behavioral intervention programs, 75 percent did not seek out the behavioral approaches.

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Multimodal Treatment Study of Children With Attention Deficit and Hyperactivity Disorder (MTA)
This study has been completed.
First Received: November 2, 1999 Last Updated: March 26, 2008 History of Changes
Sponsored by: National Institute of Mental Health (NIMH)
Information provided by: National Institute of Mental Health (NIMH)
ClinicalTrials.gov Identifier: NCT00000388
Purpose

This trial is a continuation of the Multimodal Treatment Study of Children with Attention Deficit Hyperactivity Disorder (MTA Study). Continuation Aim 1 is to track the persistence of intervention-related effects as the MTA sample matures into mid-adolescence, including subsequent mental-health and school-related service utilization patterns as a function of MTA treatment experience (treatment assignment) and outcome (degree of treatment success at 14 mo.). Aim 2 is to test specific hypotheses about predictors, mediators, and moderators of long-term outcome among children with ADHD (e.g., comorbidity; family functioning; cognitive skills; peer relations) that may influence adolescent functioning (either independent of or through initial treatment assignment and/or 14-month treatment outcomes); and to compare how these predictors, mediators, and moderators are similar or dissimilar within the normal comparison group. Aim 3 is to track the patterns of risk and protective factors (including their mediation or moderation by initial treatment assignment and/or outcome) involved in early and subsequent stages of developing substance-related disorders and antisocial behavior. Aim 4 is to examine the effect of initial treatment assignment and degree of treatment success on later academic performance, achievement, school conduct, tendency to drop out, and other adverse school outcomes.

In the original MTA design, patients were randomly assigned to 1 of 4 treatment conditions: (1) medication only; (2) psychosocial only; (3) combined (medication and psychosocial); or (4) Assessment-and-Referral condition. All but the latter were treated intensively for 14 months, with assessments for all subjects at baseline, 3, 9, 14, and 24 months. The original MTA design thus provides short-term (10 months post-treatment) follow-up at 24 months. This continuation extends the follow-up to assessments at 36, 60, and 84 months after treatment.

A child may be eligible for this study if he/she:

Is 7 - 9 years old, and has Attention Deficit Hyperactivity Disorder (ADHD).

Condition Intervention Phase
Attention Deficit Disorder With Hyperactivity
Substance-Related Disorders
Dyssocial Behavior
Behavioral: Psychosocial treatment
Drug: Anti-ADHD medication
Behavioral: Assessment-and-Referral
Phase IV

MedlinePlus related topics: Attention Deficit Hyperactivity Disorder Child Mental Health Mental Health
U.S. FDA Resources
Study Type: Interventional
Study Design: Treatment, Randomized
Official Title: Multimodal Treatment Study of Children With ADHD

Further study details as provided by National Institute of Mental Health (NIMH):

Study Start Date: September 1998
Estimated Study Completion Date: November 1999
Detailed Description:

This trial is a continuation of the Multimodal Treatment Study of Children with Attention Deficit Hyperactivity Disorder (MTA Study). Continuation Aim 1 is to track the persistence of intervention-related effects as the MTA sample matures into mid-adolescence, including subsequent mental-health and school-related service utilization patterns as a function of MTA treatment experience (treatment assignment) and outcome (degree of treatment success at 14 mo.). Aim 2 is to test specific hypotheses about predictors, mediators, and moderators of long-term outcome among children with ADHD (e.g., comorbidity; family functioning; cognitive skills; peer relations) that may influence adolescent functioning (either independent of or through initial treatment assignment and/or 14-month treatment outcomes); and to compare how these predictors, mediators, and moderators are similar or dissimilar within the normal comparison group. Aim 3 is to track the patterns of risk and protective factors (including their mediation or moderation by initial treatment assignment and/or outcome) involved in early and subsequent stages of developing substance-related disorders and antisocial behavior. Aim 4 is to examine the effect of initial treatment assignment and degree of treatment success on later academic performance, achievement, school conduct, tendency to drop out, and other adverse school outcomes.

In the original MTA design, patients were randomly assigned to 1 of 4 treatment conditions: (1) medication only; (2) psychosocial only; (3) combined (medication and psychosocial); or (4) Assessment-and-Referral condition. All but the latter were treated intensively for 14 months, with assessments for all subjects at baseline, 3, 9, 14, and 24 months. The original MTA design thus provides short-term (10 months post-treatment) follow-up at 24 months. This continuation extends the follow-up to assessments at 36, 60, and 84 months after treatment.

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ADHD注意欠陥多動障害の長期薬物療法の有効性に議論/米国医療事情 医師の一分/BIGLOBEウェブリブログ
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