Background: Cranial autonomic symptoms (CAS) are distinguishing features of trigeminal autonomic cephalalgias (TAC), of which cluster headache (CH) is the most common, but they can occur in migraine patients. For migraine with strictly unilateral headache, the presence of CAS might cause diagnostic confusion with CH. Characteristics of CAS in migraine and comparisons with those in CH have rarely been reported.
Methods: This study prospectively recruited consecutive migraine and CH patients treated at a headache clinic. We surveyed six CAS items including: conjunctival injection, lacrimation, nasal congestion, rhinorrhea, eyelid edema and forehead/facial sweating. The CAS characteristics recorded included laterality, intensity, time sequence and consistency with headache attacks.
Results: We recruited 786 migraine patients (625F/161M, mean age 40±13 years) and 98 (11F/87M, mean age 36±11 years) CH patients. The prevalence of ≥1 CAS in migraine patients was 56% and did not differ among migraine subtypes. Except for forehead/facial sweating, the features of the other CAS differed between patients with migraine and CH: CAS in migraine tended to be bilateral (odds ratio (OR): 5.8-23.8 among different CAS), be unrestricted to the headache sides (OR: 5.0-20.4), appear with mild-to-moderate intensity (OR: 1.7-7.7) and be inconsistent with headache attacks (OR: 2.8-6.7).
Conclusions: CAS were present in half of our migraine patients and the clinical features may help differentiate migraine from CH.