[1] Univ Copenhagen, Herlev & Gentofte Hosp, Dept Dermatol, Copenhagen, Denmark
[2] Univ Copenhagen, Herlev & Gentofte Hosp, Dept Allergy, Copenhagen, Denmark
[3] Univ Copenhagen, Herlev & Gentofte Hosp, Dept Cardiol, Copenhagen, Denmark
[4] Univ Copenhagen, Rigshosp Glostrup, Fac Hlth & Med Sci, Danish Headache Ctr, Copenhagen, Denmark
[5] Univ Copenhagen, Rigshosp Glostrup, Fac Hlth & Med Sci, Dept Neurol, Copenhagen, Denmark
[6] Odense Univ Hosp, Dept Neurol, Odense, Denmark
[7] Univ Southern Denmark, Fac Hlth Sci, Dept Clin Res, Odense, Denmark