Juliet Rix
http://www.timesonline.co.uk/article/0,,2682-2160195.html
The number of children with autism has risen dramatically in recent years. In a new book, Richard Lathe argues that pollution and environmental causes may be to blame
At the age of 3, James started to regress. His speech got worse until "he was really only echoing and all he did was run around hardly looking at anyone", says Chris, his father. Severe classic autism was diagnosed. The NHS offered no suggestions for treatment so his desperate parents did their own research, dug into their savings and started to do whatever they thought might help.
They put James on a gluten and casein (milk)-free diet and nutritional supplements. "There was an immediate improvement in concentration," his father says, making behavioural therapy more useful. James was found to have high levels of certain chemicals, porphyrins, in his urine, indicating excess mercury in his body. This is now being slowly removed. Eighteen months on from the diagnosis, James is still an autistic child, but, says his father, "his IQ is up from 82 to 120, his autism score has fallen dramatically, and we can sit and read a book to him again".
Thousands of parents like Chris, despairing of the mainstream treatment
(or lack of it) offered to their autistic children, are turning to biomedical interventions that they believe treat physical causes of their children's behavioural problems.
Such interventions are scientifically unproven and many experts are sceptical. But there is a growing body of research and anecdotal evidence, and a new book to be published later this month, Autism, Brain and Environment by Richard Lathe, draws it together along with the theoretical science behind it. One of this country's leading autism researchers, Simon Baron-Cohen, Professor of Developmental Psychopathology at the University of Cambridge, describes Lathe as " an excellent scientist", and his book as "a masterly review . . . a serious summary of the science of autism".
Lathe believes that not only are parents like Chris right in thinking that biomedical intervention can help their children, but that some of these interventions may be getting to the heart of environmental "causes" of autism.
The number of people -- and particularly young children -- who have autistic spectrum disorders (ASD) has risen dramatically over the past two decades. ASD used to be identified in a few children in every
10,000: it now affects as much as 1 per cent of the population. Part of this rise is certainly due to a broader definition and increased diagnosis, but some experts are convinced that there has also been a real rise. Lathe is one, and he believes that this is in part due to an increase in environmental toxins -- pesticides, PCBs (from plastics) and particularly heavy metals including mercury and lead (both known neurotoxins).
He is not suggesting that pollution is the sole cause of autism. It is now well established that genes play a major role in the disorder. The genetics is not, however, straightforward. No "autism" gene has been identified -- nor is one expected. Autistic tendency runs in families but there are pairs of identical twins, one of whom is autistic while the other is not. Genes predispose to ASD but in most cases something more is needed to trigger the development of autism -- something in the environment. Sir Michael Rutter, Professor of Developmental Psychopathology at King's College London, a leading authority on autism, says the days when bad parenting was blamed are long gone and that "the environmental factors are likely to be physical rather than psychological".
All sorts of things have been suggested, from infections to diet, complications of pregnancy and birth to vaccines -- all of which are currently being investigated by the Avon Longitudinal Study of Parents and Children at Bristol University. Lathe points to research showing that autism is more prevalent in cities than in rural areas to support his view that pollution may be implicated.
He emphasises that nothing in his book contradicts the genetic research. "I aim to show how genetics and environmental factors might come together," he says.
Lathe argues that many cases of autism could be caused by a genetically determined frailty in the body's biochemistry that makes it less able to deal with particular pollutants. So when the individual is exposed to toxins (even at levels that have no ill-effect on most of the population) their bodies cannot cope. If exposure is at a vulnerable stage of development (foetal, neonatal or at significant points in brain development) the toxins may cause damage to key areas of the brain.
"People with autism have a diverse set of physiological impairments such as hormone imbalances, gut problems and immune system deficiencies in addition to their psychological and cognitive difficulties," says Lathe. Practitioners have often chosen to ignore these, he adds, preferring to see the physical and psychological as separate. But "recent evidence contradicts this", he says.
It is well established that exposure to certain toxins can cause brain damage and that brain damage (particularly in the limbic system) can lead to autistic symptoms. What is more, the limbic brain is known not only to affect emotions and behaviour, but also to play a major role in regulating the body's physiology. So the initial brain damage may go on to cause further physical problems, which, in a vicious cycle, could in turn cause yet more damage to the brain.
Can biomedical intervention break this cycle and ameliorate or even reverse the damage? Unlike most of the brain, the limbic area has some ability to repair itself, Lathe says. "So there are prospects of some degree of recovery if the specific problem can be identified and treated . . . as early as possible."
While noting that there is currently no conclusive evidence in favour of biomedical intervention in autism, Professor Rutter says such treatments do work in other conditions. Phenylketonuria (PKU), for instance, is an inherited enzyme deficiency which if left untreated causes brain damage
(sometimes producing autistic symptoms). "PKU has a purely genetic cause but is almost entirely remedied by a change of diet," he says.
There is a close neurological connection between the gut and the brain and a study by Research Autism found that 60 per cent of families with an autistic child were using casein and/or gluten-free diets.
"I know a lot of children on these diets who have been dramatically improved," says Richard Mills, director of Research Autism. "I also know plenty for whom they made no difference."
This may be because autism is not a single disorder. It is defined only by a collection of behaviours that could have multiple causes. This would also explain why autism research often produces contradictory results. Experts agree that finding ways to distinguish between autistic subgroups is crucial so that research and treatment can be better targeted.
Lathe is in little doubt that individually tailored biomedical intervention can help children like James. What is more, he says, if we could reduce toxins in our environment we might bring down the number of cases not only of autism, but also of Alzheimer's (in which there is increasing evidence of a link with heavy metals), schizophrenia, ADHD and perhaps even the much reported bad behaviour in schools.
Autism, Brain and Environment by Richard Lathe (Jessica Kingsley, £15.99)
What parents of autistic children can do:
# Reduce as much as possible your child's exposure to pollution and toxic chemicals. Levels that may not affect the child next door may still affect and autistic child.
# Filter tap water through activated charcoal to remove pollutants.
# Eat organic.
# Try to avoid heavy metal intake. Limit seafood, which can be high in heavy metals - particularly swordfish and tuna (but be aware of the impact on nutrition.
# Keep a close eye on your child's physical wellbeing, especially if he or she cannot effectively communicate. Unrecognised pain can lead to extreme problems that may be connected to autism.
# Be aware that your child may have gastrointestinal problems
(diarrhoea, constipation, pain). If so, get the child treated. GI abnormalities may play a causal role (through neurological and biochemical connections with the brain).
# Try to limit social and psychological stress; stress chemicals can also induce limbic brain damage.
# Gluten and/or casein free diets may help (again be careful that good overall nutrition is maintained).
# Consider nutritional supplements - folic acid, selenium, B vitamins, vitamin C etc.
# Encourage proper recycling. Dumping of electrical goods and other rubbish helps to poison groundwater.
# If your child is shown to have excess levels of heavy metals consider chelation (the removal of metals from the body by binding to other chemicals) but do this with only reliable evidence that it is necessary and under proper supervision.
Further information: National Autistic Society
http://www.nas.org.uk
0207 8332299
Autism research Institute
http://www.autismwebsite.com/ari
Informant: Teresa Binstock
