Abstract text (incl. figure legends and references)

Background: There are few data about patients whose migraine headaches predominantly affect the head's back.

Methods: Retrospective analysis of patients with the diagnosis of episodic or chronic migraine (according to the ICHD-3 classification) with posterior (occipital and back of neck) onset and predominant location from 2013 to 2020.

Results: We identified 60 patients (mean age of headache onset: 27 years old; 81.6% were female) with episodic (78.3%) or chronic migraine (21.7%) with the posterior onset and predominant location. We identified 3 patterns of pain: patients with only posterior localized migraine (25; 41.7%); posterior and temporal or parietal migraine (posterior plus migraine; 16; 26.7%); and posterior onset with holocranial irradiation of pain (19; 31.6%). Regarding the headache characteristics, the most frequent pattern was bilateral or alternating pain (40% each); 63,4% described photophobia or phonophobia plus nausea or vomiting; 28.3% reported aura. The duration of each attack was mostly <48hours (61.8%). Most patients had <5 episodes of migraine attacks/month (51.8%). Only 10 patients (16.7%) reported modification of pain pattern since the onset of migraine. Regarding the treatment, 53.3% of the patients reported failure of at least one drug for the acute phase and 20% had a failure with at least one prophylactic drug. We identified that 18.4% of the patients also had a medication-overuse headache. Forty-three patients (71.7%) started a prophylactic drug. During follow-up, only 14 patients had treatment response (defined as a reduction in ≥50% of monthly headaches).

Conclusions: In our cohort, patients with posterior predominant migraine have a young-onset headache, mostly localized pain, a short duration of each attack, and a low frequency of monthly headaches. In the future, it would be important to understand if there are clinical and therapeutic differences between patients with posterior versus anterior predominant migraine.