[1] Univ Cologne, Dept Neurol, Cologne City Hosp, D-51109 Cologne, Germany
[2] Univ Essen Gesamthsch, Dept Neurol, Essen, Germany
[3] Paul Ehrlich Inst, D-6070 Langen, Germany
[4] Univ Essen Gesamthsch, Inst Med Informat Biometry & Epidemiol, Essen, Germany
[5] Univ Essen Gesamthsch, Inst Transfus Med, Essen, Germany