Is gluten linked to disorders of the nervous system?
In 1999 researchers Davies-Jones, Gibson, Hadjivassiliou, Lobo, Milford-Ward and Stephenson found indications that there was a positive correlation between sensitivity to ingested gluten and undiagnosed neurological illnesses. Gluten sensitivity can be detected by measuring the markers ( IgG and IgA – Antigliadin antibodies )of the autoimmune functions the body generates to respond to bowel irritation caused by gluten. For gluten sensitive/ celiac sufferers, the bowel is irritated by gluten and therefore the body causes a response that increases fluid and blood flow to the bowel in order to protect and heal.
57% of the un-diagnosed neurological disorder group in this study were found to be gluten sensitive and of those tested positive for antigliadin antibody acitivity, 35% were found to have undiagnosed celiac disorder, 37% were found to have undiagnosed duodenitis and only 26% had no significant evidence of severe gluten sensitivity. Interestingly, when compared to a control group of those with diagnosed illnesses of the nervous system i.e. stroke, parkinsons, multiple sclerosis etc, only 5% were found to have traces of IgG and IgA. Combined with a third control of 50 healthy-blood participants there was a 95% difference in results. Accounting for a 5% P value, this study found that there is significant evidence to link non-specific neurological disorders with gluten sensitivity.
It should not however be concluded that one is the proponent of the other. There was no suggestion made by Davies-Jones et al (1999) that gluten/ non-specific neurological disease is the cause or the effect of the other. There just happens to be a relationship in this group.
The researchers here used a total participating population of 197 participants. This is a relatively large number for a pilot study and under statistical analysis would show that there may be some significance of results in a larger population. These results could potentially be used as an indication that there may be undiagnosed neurological condition in celiac/ gluten-sensitivity sufferers and vice versa.
Green and Jabri (2003) suggest that celiac (or coeliac) disease is as common as 1 in 250 meaning that up to 280,000 people in the UK have been diagnosed. In the context of neurological disease, extrapolating the evidence found by Davies-Jones et al (1999), up to 57% of these sufferers could have non-specific or undiagnosed neurological illnesses; 159600 people in real terms.
Further studies in to neurological illness in adult celiac sufferers were noted in an editorial review by Davies-Jones, Grunewald and Hadjivassiliou (Journal of Neurology, Neurosurgery and Psychiatry with Practical Neurology, 2002). In the first instance, 41% of idiopathic sporadic ataxia, a disease that causes atrophy (destructive shrinking) of the cerebellum and has incidence in those with no family history of ataxia, had gluten sensitivity. In idiopathic Sporadic Ataxia symptoms of Parkinsons disease are often developed in addition to autonomic failure and further multi-system atrophy. In other words this shows a potential link (however insignificant 59 out of 143) between gluten celiac disease or some form gluten sensitivity and degenerative neurological disorders in later life.
In the second instance reported by Davies-Jones et al (2002) shows a 40% positive correlation between peripheral neuropathy and gluten sensitivity. Peripheral neuropathy is a chronic disease that inhibits signal transfer between sensory axonal nerves to the skin and outer limits of the body and the spinal cord affecting touch and feel senses. In the worst case peripheral neuropathy can also affect other sensory nerves in the nasal passage, eyes, mouth and ears.
The results here by these researchers are far from conclusive; in two-thirds of cases there is less than a 50% link between gluten sensitivity and neurological conditions. Despite this there is some argument as to the relationship between the number studies that have similar findings and something conclusive.
It is the opinion of this researcher that it is not a fair conclusion to state that gluten causes or is a direct effect of serious neurological disorders in celiac or non-celiac sufferers. However the regularity of findings should pose some indication and beg some consideration to the possibility that those with one may have or may develop the other in later life, further compounding the argument for long-term adherence to a gluten-free diet.
References
Davies-Jones, G., Gibson, A., Hadjivassiliou, M., Lobo, A., Milford-Ward, A., Stephenson, T. (1996). Does cryptic gluten sensitivity play a part in neurological illness? The Lancet, 347; 8998: 369-371.
Davies-Jones, G., Grunewald, R., Hadjivassiliou, M., (2002). Gluten sensitivity as a neurological illness. Journal of Neurology, Neurosurgery and Psychiatry with Practical Neurology, 72: 560-563.
Green, P., Jabri, B. (2003) Coeliac Disease. The Lancet, 362; 9381: 383-391.
