Migraine Does Not Affect Pain Intensity Perception: A Cross-Sectional Study

Objective. To explore perceived pain intensity (PPI) in three drug-naive patient groups characterized by homogeneous migraine phenotypes-migraine without aura without cutaneous allodynia (MwoA CA-), MwoA with ictal CA (MwoA CA+), and migraine with aura without cutaneous allodynia (MwA CA-)-compared with age-and sex-matched healthy controls (HCs). Methods. Using trigeminal heat stimulation (THS) at three different predefined intensities (41 degrees C, 51 degrees C, and 53 degrees C) performed by the contact heat-evoked potential stimulator (CHEPS), PPI was investigated in 34 patients with MwoA CA-, 30 patients with MwoA CA+, and 30 patients with MwA CA-compared with 30 age-and sex-matched HCs. The patients had never taken migraine-preventive drugs, and they were investigated during an interictal period to avoid confounds associated with migraine attack. Secondary analyses evaluated associations between PPI and clinical features of migraine in patients. Results. No significant differences were observed between the four groups for each experimentally induced stimulus. Moreover, no significant correlations were found between clinical variables and the PPI of the THS at any level of experimental stimulus. Conclusions. Despite the converging evidence of pain threshold abnormalities in migraine patients, our findings suggest that migraine patients did not exhibit differences in the PPI of THS when compared with HCs, independent of phenotype and migraine severity, as well as somatic, psychiatric, or pharmacological interferences. This may depend on both the nature of the pain stimulus experienced and the involvement of selective regions or specific pain processing pathways.