SAN DIEGO, Oct. 30 -- Preliminary results of a small ongoing study of vitamin B12 injections for children with autism showed no signs of significant benefit, researchers reported here, but they remained hopeful.
So said Lesley J. Deprey, Ph.D., of the University of California at Davis, and colleagues, in a poster presentation at the American Academy of Child and Adolescent Psychiatry meeting here.
Their hope, they noted, derived from "anecdotal reports of remarkable clinical improvements" using subcutaneous vitamin B12 (methyl cobalamin), although there have been no supporting published studies. Vitamin B12 is an antioxidant involved in metabolism pathways for cellular methylation, which has been implicated in other neurological disorders like schizophrenia and Alzheimer's Disease.
The researchers reported that no significant benefits have turned up yet for the 14 patients who have completed three months in the current double-blind crossover study. They found no significant differences with active versus placebo treatment for the following measures:
- Clinical Global Impression Scale Improvement (P=0.4129),
- Peabody Picture Vocabulary Test scores (P=0.2895), and
- Social Communication Questionnaire verbal results (P=0.4211).
A significant improvement found for nonverbal Social Communication Questionnaire scores in the vitamin B12 group compared to placebo (P=0.0309) disappeared after adjusting for multiple testing.
The researchers randomized half of the participants to six weeks of 64.5 ug/kg of subcutaneous methyl cobalamin injections every three days and the other half to a similar schedule of saline injections disguised to maintain the double-blind. For the following six weeks, the children were crossed over to the opposite group.
Diagnosis of autism was confirmed using several clinical measures including the Vineland Adaptive Behavior Scales, Autism Diagnostic Observation Schedule, and Mullen Scales of Early Learning. Patients could stay on all other treatment modalities they entered with but no additions were allowed during the trial.
Interestingly, several of the children seemed to respond well. Three of the eight participants who subsequently completed three months of open-label therapy and two of the five who have completed six months were rated "much improved" on the Clinical Global Impression Improvement scale.
"While there is a general trend toward improvement in several of the subjects, this trend does not reach group significance with this small sample size," said Dr. Deprey.
"Autism is so heterogeneous," she said, "you can't expect one treatment is going to work for all kids with autism."
The real usefulness of the study may be to indicate which patients will respond to the treatment, which is generally thought to have few side effects, commented Raum Melmed, M.D., of the Southwest Autism Research and Resource Center in Scottsdale, Ariz.
He said the study does not have a traditional design and will likely be scrutinized critically. However, he praised it as a "wonderful bridge" between research and the complimentary and alternative medicine that so many patients are using where "ground needs to be broken."
The researchers said they plan to enroll at least 42 children in the study, which was supported by the University of California at Davis.
Primary Source
American Academy of Child and Adolescent Psychiatry
Source Reference: Deprey LJ, et al "Double-Blind, Placebo-Controlled, Cross-Over Trial of Subcutaneous Methylcobalamin in Autism: Preliminary Results" AACAP 2006; 33:F47.