[1] Oulu Univ Hosp, Med Res Ctr Oulu, Dept Dermatol, Res Unit Clin Med, Aapistie 5 A, FIN-90220 Oulu, Finland
[2] Univ Oulu, Aapistie 5 A, Oulu 90220, Finland
[3] Univ Helsinki, Dept Dermatol & Allergol, Helsinki, Finland
[4] Helsinki Univ Hosp, Helsinki, Finland
[5] Univ Oulu, Infrastruct Populat Studies, Oulu, Finland