The gluten-free casein-free diet in autism revisited

by Benison O'Reilly on Wednesday, June 23rd, 2010

In the Australian Autism Handbook, published a couple of years ago now, we discuss the gluten-free casein-free (GFCF) diet and the evidence for its use in ASDs.

We include mention of an ongoing— at that time—double-blind randomised controlled trial (RCT):

Currently the US National Institute of Mental Health (NIMH) is supporting a double-blind RCT to study the effectiveness and safety of GFCF diet. Thirty children following a GFCF diet will either be challenged with snacks which contain gluten and casein or receive identical placebo snacks. All children in the study will be receiving intensive behavioural intervention so that the effects of their early intervention program cannot influence the results. Researchers will try to identify the characteristics of children who are responders and the nature of that response. You can read about this trial at: http://clinicaltrials-nccs.nlm.nih.gov

Well, the preliminary results of that trial are now in and were presented at the recent International Meeting for Autism Research (IMFAR), held last month in Philadelphia. Unfortunately we only have an abstract to go on, and should probably reserve complete judgement until the full published paper is available for review, but this is a summary of  the research:

Children aged 30-54 months, receiving at least 10 hours/week of early intensive behavioural intervention (EIBI) were recruited. They were screened for milk/wheat allergies, coeliac disease, and anaemia prior to starting treatment.

After a strict GFCF diet for at least 4 weeks, they received weekly randomised, double-blind challenges (snacks) containing either 20 g wheat flour, 20 g evaporated milk, both, or neither on three separate occasions over 12 weeks . The snacks appeared identical and were similar in taste and texture.  Behavioural and other data was collected at baseline and at regular intervals throughout the 30-week trial; as well as prior to, and two and 24 hours after, the snack challenges.

In the end twenty one children were recruited. Of these, seven were eventually excluded from the analysis for medical or other reasons, leaving only 14 participants (12 male), with an average age of just over three and half years.

The researchers found no statistical change in frequency or quality of stools, sleep, activity measured by actigraphy*, or parent/teacher/observer scores of attention or activity when children’s baseline (before diet) measures were compared with treatment (during diet) measures. Nor did they detect any changes pre/post the gluten and/or casein challenges. In fact, one group measure of behaviour** actually improved 2 hours-post gluten &/or casein challenge, although in light of the small patient numbers this might be a chance finding.

The authors concluded:

This is the first study to examine the behavioral effects of a nutritionally monitored GFCF diet on attention, sleep, stool pattern, and core symptoms of ASD. While no favorable effects of the GFCF diet on attention, sleep and stool patterns were identified in group analyses, such effects may occur for individuals or for subgroups of children   (e.g. with significant GI disease), providing the basis for positive anecdotal reports.  Future studies need to address the potential effects of nutrition on behavior in children with ASD and be powered to evaluate subtle changes in core symptoms.

The abstract is available below:

http://imfar.confex.com/imfar/2010/webprogram/Paper6183.html

This is the second double-blind study to find no effect for the GFCF diet in young children with ASD. It may be, as the authors say, that there is a subgroup of children—possibly those with significant gastrointestinal symptoms—who do benefit dramatically from the diet, and more trials with greater patient numbers are clearly needed.  Nonetheless this adds to the body of evidence that not all kids on the autism spectrum will respond to the GFCF diet.

Those who are interested might also want to check out the latest Cochrane Review of the GFCF diet, updated in 2009 but prior to presentation of this latest study:

www.mrw.interscience.wiley.com/cochrane/clsysrev/articles/CD003498/frame.html

*According to Wikepedia, actigraphy is a relatively non-invasive method of monitoring human rest/activity cycles, commonly using a wrist-watch-like package. The unit continually records movements, which are later analysed by computer.

** The Ritvo Freeman Real Life Rating Scales (RFRLRS). This scale was developed to assess effects of treatment on 47 recognised behaviours of patients with autism. It is applicable in natural settings & can be used by nonprofessional raters.

Tags: autism, diet, research