[1] Cent Inst Mental Hlth, Dept Addict Behav & Addict Med, D-68159 Mannheim, Germany
[2] Heidelberg Univ, Dept Visceral & Gen Surg, D-6900 Heidelberg, Germany
[3] Heidelberg Univ, Dept Gen Psychiat, D-6900 Heidelberg, Germany
[4] Heidelberg Univ, Dept Psychosomat & Clin Med, D-6900 Heidelberg, Germany