Trigger factors for familial hemiplegic migraine.

OBJECTIVE: The aim was to identify and describe migraine trigger factors in patients with familial hemiplegic migraine (FHM) from a population-based sample.

METHODS: 127 FHM patients were sent a questionnaire listing 16 trigger factors. Distinction was made between attacks of hemiplegic migraine (HM) and migraine with aura (MA) or without aura (MO) within each patient.

RESULTS: The response rate was 59% (75/127) of whom 57 (76%) had current HM attacks. Sixty-three per cent (47/75) reported at least one factor triggering HM, and 36% (27/75) reported at least one factor that often or always caused HM. Twenty per cent (15/75) reported only HM, whereas FHM in combinations with MA and MO were reported by 80% (60/75). Stress (with attacks either following or during the stress), bright light, intense emotional influences and sleeping too much or too little were the trigger factors mentioned by most.

CONCLUSION: Many FHM patients report trigger factors and one-third reported at least one trigger factor often or always triggering FHM. The typical triggers are the same as for MA. Patients should be educated to avoid these factors. The role of trigger factors in the onset of new or first attacks of FHM remains unknown.