Something that is not often freely discussed in connection with celiac disease is the neurological symptoms can affect up to 10% of celiacs. The most common of these neurological manifestations are ataxia, which is characterized by lack of coordination of muscle movements, and peripheral neuropathy which is caused by damage to the nerves of the peripheral nervous system. Rarely, epilepsy can result from gluten sensitivity.
About 20 million Americans suffer from peripheral neuropathy. About a third of these are diabetics, but about a quarter of patients with established celiac disease on a gluten-free diet also show evidence of peripheral neuropathy. Neuropathy is caused by damage to the nerves and can manifest as tingling, numbness, pain or weakness in the hands and feet. Gluten neuropathy is a slow-onset disease with a mean age of onset of 55 years, but can commence at any age. Adopting a gluten-free diet significantly improves symptoms, but it can take some time for the peripheral nerves to recover from the damage.
Ataxia is one of the most common manifestations of gluten sensitivity. Gluten ataxia is characterized by balance disturbances. Ataxia primarily affects gait, but can also affect the arms and can be accompanied by tremors. In a small study carried out in England on gluten-sensitive people suffering from ataxia, they found that ataxia improved markedly on adopting a gluten-free diet. However, since some celiacs also experience episodes of dizziness and other disorders affecting balance, these are also likely to be contributing factors to walking problems in some people.
A specific type of focal epilepsy has been reported in gluten sensitive people, especially in Italy. Reports of the prevalence of epilepsy among celiac patients varies from 1% to 5%, and these are mainly temporal lobe epilepsy which causes fits or seizures.
In order to study blood flow to the brain, otherwise known as perfusion, a group of people with untreated celiac disease and another group of people who had been treated for celiac disease were analyzed, together with a control group of healthy people. Using an imaging technique called single photon emission computed tomography (SPECT) to examine various regions of the brain, the researchers carried out a study to assess the perfusion of the brain.
Of the 15 untreated CD patients, 11 had at least one under-perfused brain region, compared with only one of the 15 patients on a gluten free diet. This was not observed in any of the healthy controls. Cerebral perfusion in celiacs on a gluten-free diet and healthy volunteers was found to be identical. Blood flow to the brain of the untreated patients was significantly lower in 7 of the 26 regions studied. Defects were mainly in the anterior and superior regions of the frontal cortex. They noted that depression and anxiety were common in the untreated patients. Treated patients had less anxiety but not depression. They concluded that reduced blood flow to areas of the brain may be related to excessive blood flow to the intestines, malabsorption or iron-deficiency anemia.
Interestingly, neurological symptoms can be present in gluten-sensitive people who do not experience any intestinal symptoms at all. Many theories abound as to what exactly causes these neurological symptoms. The authors of the above study concluded that these symptoms could be immune-mediated. Others postulate that they are of inflammatory origin, which is essentially the same thing. However, the gut-brain connection (more fully explained in my article on sleep disorders) whereby messages are sent from the gut to the brain, could well be at the root of these neurological symptoms.