Toshiko Matsudaira: Child & Adolescent Psychiatry, Institute of Psychiatry, King's College London – is currently setting up a study on Attention Deficit and Hyperactivity Disorders (ADHD), which includes impulsivity and poor coordination, leading to behaviour problems and conduct disorders. 3-10% of children suffer ADHD, 5% of school-age children. The male to female ratio is 4:1. 70-80% of children with ADHD continue as adolescents to have social, academic, and emotional difficulties, and some lifelong.
Genetic factors are still unknown. They are the subject of: twin studies; molecular genetic research; adoption studies; and family studies. Indications are that ADHD is 70% hereditary. Environmental factors include child abuse. Treatment is multimodal: medication; parent training; cognitive/behavioral approach; also social skills training including anger management. Nutritional supplements are being tried including carnitine (an amino acid responsible for transport of fatty acids into a cell's mitochondria); zinc; iron; vitamin E; omega3 fatty acids etc.
Stimulants have been used since the 1950s, particularly Ritalin (methylphenidate) and Dexedrine (dextroamphetamine), with some 75% response rate. Recently, non-stimulant medication – Atomoxetine or Strattera (atmoxetine hydrochloride), whose structure is similar to an antidepressant, has been used. But medicines have the problem of possible side effects such as growth retardation; appetite loss; headache; stomach ache; insomnia; and in patients with a history of seizures they can lower the seizure threshold. Their use can be followed by addiction or suicide (Atomoxetine for instance). Because of short or long term side effects, ADHD patients often choose alternative treatment such as supplementation.
The way omega3s benefit ADHD is uncertain. They may be important in remodelling dendrites and synapses, and/or sustaining several features: blood brain barrier, neuronal membrane, neurotransmitter channel, receptors and ion channels.
Innis in 1994 and in 2003 found that omega-3 deficient rats showed hyperactivity. Burgess in 2000 showed that the reason for ADHD cases’ lower levels of omega-3 was not lower intake or absorption. Whether it could be enhanced metabolism or inefficient conversion of EFAs to LCPUFAs might be determined by carbon-dated traces or by scans.
Boys need more omega3s than girls, and this may be connected with boys’ prevalence of ADHD. Aggression increased in rats deprived of DHA but normalized as DHA was restored.
Richardson5 found PUFA were effective for cognitive problems and behaviour problems in ADHD/dyslexia. Stevens (2003) found them effective for oppositional defiant disorder, whereas EPA specifically was helpful with disruptive behaviour. DHA is important during gestation and early infancy, particularly for neurodevelopment. It may improve aggression. EPA is crucial throughout life, particularly for optimum cognitive function.
In the Durham Trial5, 120 school children aged 6-12yrs with developmental coordination disorder, were tested with omega3s with 6s. After 3 months without, they had 3 months on the EPA. ADHD scores on co-ordination and short-term memory were improved when taking fatty acids. However, this trial was not only for ADHD-diagnosed children, nor did it involve EPA alone. Most needed now are: test of pure EPA vs. pure DHA; metabolic study; non-
invasive methods to find essential fatty acid deficiencies; brain function assessment; genetic; gender difference; and EFA deficiency questionnaires.
There have been several attempts to see if omega 3 fatty acids will benefit and some like the Durham school trials in the UK have given promising results.
In discussion Joe Hibbeln said that the Seychelles study found a correlation between hyperactivity generally with mothers deficient in omega 3s during pregnancy, and that the ALSPAC study indicated some correlation.
Gillian West of the Hyperactive Children’s Support Group (HACSG) said they had found for decades that, as well as omega3s, the omega6 gamma-linoleic acid (GLA) had been most beneficial: despite the general excess of omega6 observed. This was because, in contrast to the evening primrose oil they use, dietary GLA was often not easily assailable. Also many of these mothers had previously received evening primrose oil for pre-menstrual tension, indicating they had a pre-existing EFA deficiency. Reasons for poor conversion included: deficiencies in zinc, chromium, magnesium and B vitamins; toxins; disease; and ageing. HACSG had had enormous success, turning round thousands if not millions of ADHD subjects. There were calls for specific studies on GLA in ADHD.
Another puzzle raised was the effect of eicosapentaenoic acid (EPA). The suggestion was that whereas DHA may primarily be benefiting brain structure directly, EPA may primarily be benefiting blood-vessel structure and so blood-
flow to the brain.
To the question of how fully the Japanese diet appears to minimise ADHD, Matsudaira replied that it is hard to say, since the Japanese would be reluctant for knowledge of such a disorder to reach awareness beyond the home.