Dec. 4, 2001 -- The latest in a series of government-sponsored studies confirms what was already suspected -- secretin does nothing for autism. The digestive hormone had shown promise in early investigations, but the findings just haven't panned out in larger, more rigorous trials.
Autism affects the areas of the brain controlling social interaction and communication skills. Children and adults with autism have problems communicating both verbally and non-verbally and are withdrawn and unable to relate to others. They may perform repetitive movements (rocking, for example) or actions, and can become aggressive against themselves or others.
The disappointing results with secretin appear in the November issue of the Journal of the American Academy of Child and Adolescent Psychiatry.
"Our study reiterates the need to perform careful studies of any new treatment -- even one that appears promising -- before routinely prescribing it to patients," says study leader Thomas Owley, MD, in a news release. He's an assistant professor of child and adolescent psychiatry at the University of Chicago.
The researchers randomly assigned 56 autistic children, aged 3-12, to receive pig-derived secretin or placebo for four weeks. Then, for the next four weeks, the groups switched, so those who'd received secretin would then receive the placebo, and vice versa.
Before, during, and after the study, the children took the three standard tests of social and communication skills commonly used to diagnose and assess autism.
There was no significant difference in symptoms between the groups on any of the measures. Earlier studies used human-derived secretin, with similar results.
"This multi-site study analyzed possible changes in autistic symptoms based on very well-accepted measures," said Laurence Stanford, PhD, a program officer of the Mental Retardation and Developmental Disabilities branch of the National Institute of Child Health and Human Development. "The study results reinforce the findings of other controlled clinical trials on secretin that, for most people with autism, the hormone is not an effective treatment."
Others agree. "These results, in addition to those from other secretin clinical trials, do not provide evidence to support using the hormone to treat the symptoms of autism," says Duane Alexander, MD, director of the National Institute of Child Health and Human Development, in a news release.