A Ketogenic Diet Acts on Cortical But Not Subcortical Responsivity in Migraineurs

A short ketogenic diet (KD) treatment can prevent migraine attacks and correct excessive cortical response. Here, investigators aim to prove if the KD-related changes of cortical excitability are primarily due to cerebral cortex activity or are modulated by the brainstem. Through the stimulation of the right supraorbital division of the trigeminal nerve, there will be concurrently interictally recorded the nociceptive blink reflex (nBR) and the pain-related evoked potentials (PREP) in 18 migraineurs patients without aura before and after 1-month on KD, while in metabolic ketosis. nBR and PREP reflect distinct brain structures activation: the brainstem and the cerebral cortex respectively. It will be estimated nBR R2 component area-under-the-curve as well as PREP amplitude habituation as the slope of the linear regression between the 1st and the 2nd block of 5 averaged responses.

Comparison before and during ketogenic diet of trigeminal neurophysiological features in a population of patients with migraine. In particular, the nociceptive blink reflex (nBR) and the trigeminal pain-related evoked potentials (PREPs) changes of amplitude between the baseline (pre-diet) and during the diet will be used as markers of ketones activity on neural modulation. The unit of measure of the amplitude of neurophysiological evoked responses are the micronVolts (1 volt X 10^-6).

Comparison before and during ketogenic diet of latencies of trigeminal neurophysiological evoked responses in a population of patients with migraine. In particular, the latency of evoked nociceptive blink reflex (nBR) and the trigeminal pain-related evoked potentials (PREPs) changes between the baseline (pre-diet) and during the diet. The unit of measure of the latency of the neurophysiological features are the milliseconds (1 sec X 10^-3).

Comparison before and during ketogenic diet of the habituation slope of amplitudes of repeated responses to repetitive trigeminal painful electrical stimuli in a population of patients with migraine. A repetitive stimulus induces repetitive responses from the brainstem and cerebral cortex that physiologically have a decremental trend of amplitudes, also called habituation. On the contrary, in migraineurs, there is a deficit of habituation, i.e. a lack of decremental responses, both in nociceptive blink reflex (nBR) and the trigeminal pain-related evoked potentials (PREPs). The changes induced by ketogenic diet in habituation slope will be measured. The unit of measure of the slope is the radiant degree.

Inclusion Criteria: Diagnosis of migraine Kept a headache diary for at least 1 month Headache onset before the age of 50 Exclusion Criteria: over consumption of acute pain-killers (triptan, analgesic, or ergotamine) pregnancy or lactation type I diabetes serious organic or psychiatric disorders that the investigators judged as having the potential to influence the trial evaluation.

Di Lorenzo C, Coppola G, Bracaglia M, Di Lenola D, Evangelista M, Sirianni G, Rossi P, Di Lorenzo G, Serrao M, Parisi V, Pierelli F. Cortical functional correlates of responsiveness to short-lasting preventive intervention with ketogenic diet in migraine: a multimodal evoked potentials study. J Headache Pain. 2016;17:58. doi: 10.1186/s10194-016-0650-9. Epub 2016 May 31.

Di Lorenzo C, Coppola G, Bracaglia M, Di Lenola D, Sirianni G, Rossi P, Di Lorenzo G, Parisi V, Serrao M, Cervenka MC, Pierelli F. A ketogenic diet normalizes interictal cortical but not subcortical responsivity in migraineurs. BMC Neurol. 2019 Jun 22;19(1):136. doi: 10.1186/s12883-019-1351-1.