[1] Univ Uppsala Hosp, Dept Neurosci, SE-75185 Uppsala, Sweden
[2] Karolinska Univ Hosp Huddinge, Dept Neurol, Stockholm, Sweden
[3] Linkoping Univ Hosp, Dept Neurol, S-58185 Linkoping, Sweden
[4] Sahlgrenska Univ Hosp, Dept Clin Neurosci & Neurol, Gothenburg, Sweden
[5] Sundsvall Hosp, Dept Geriatr Med & Rehabil, Sundsvall, Sweden