title: Cortical excitability changes correlate with fluctuations in glucose levels in patients with epilepsy.
abstract: OBJECTIVE
  We used transcranial magnetic stimulation (TMS) to investigate motor cortical excitability changes in relation to blood glucose levels.
  
  
  METHODS
  Twenty-two drug-naïve patients with epilepsy [11 generalized and 11 focal] and 10 controls were studied twice on the same day; first after 12h of fasting and then 2h postprandial. Motor threshold and paired-pulse TMS at a number of short and long interstimulus intervals were measured. Serum glucose levels were measured each time.
  
  
  RESULTS
  Decreased long intracortical inhibition was seen in patients and controls during fasting compared to postprandial studies. This effect was much more prominent in patients with generalized epilepsy (with effect sizes of up to 0.8) in whom there was also evidence of increased intracortical facilitation (effect size: 0.3).
  
  
  CONCLUSIONS
  Cortical excitability varies with fluctuations in blood glucose levels. This variation is more prominent in patients with epilepsy. Decreased glucose levels may be an important physiological seizure trigger.
authors.affiliation: Department of Clinical Neurosciences, St Vincent's Hospital, Fitzroy, Australia. badawyr@unimelb.edu.au
authors.forename: Radwa A B
authors.initials: RA
authors.lastname: Badawy
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Vogrin
authors.forename: Alan
authors.initials: A
authors.lastname: Lai
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Cook
mesh_terms: D000293:Adolescent; D000328:Adult; D001786:Blood Glucose; D002540:Cerebral Cortex / Q000503:physiopathology*; D004569:Electroencephalography; D004576:Electromyography; D004827:Epilepsy / Q000097:blood* / Q000473:pathology*; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D013223:Statistics as Topic; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult
chemical_list: D001786:Blood Glucose