title: Specificity of affective instability in patients with borderline personality disorder compared to posttraumatic stress disorder, bulimia nervosa, and healthy controls.
abstract: Affective instability is a core feature of borderline personality disorder (BPD). The use of advanced assessment methodologies and appropriate statistical analyses has led to consistent findings that indicate a heightened instability in patients with BPD compared with healthy controls. However, few studies have investigated the specificity of affective instability among patients with BPD with regard to relevant clinical control groups. In this study, 43 patients with BPD, 28 patients with posttraumatic stress disorder (PTSD), 20 patients with bulimia nervosa (BN), and 28 healthy controls carried e-diaries for 24 hours and were prompted to rate their momentary affective states approximately every 15 minutes while awake. To quantify instability, we used 3 state-of-the-art indices: multilevel models for squared successive differences (SSDs), multilevel models for probability of acute changes (PACs), and aggregated point-by-point changes (APPCs). Patients with BPD displayed heightened affective instability for emotional valence and distress compared with healthy controls, regardless of the specific instability indices. These results directly replicate earlier studies. However, affective instability did not seem to be specific to patients with BPD. With regard to SSDs, PACs, and APPCs, patients with PTSD or BN showed a similar heightened instability of affect (emotional valence and distress) to that of patients with BPD. Our results give raise to the discussion if affective instability is a transdiagnostic or a disorder-specific mechanism. Current evidence cannot answer this question, but investigating psychopathological mechanisms in everyday life across disorders is a promising approach to enhance validity and specificity of mental health diagnoses.
authors.affiliation: Department of Sport and Sport Science, Karlsruhe Institute of Technology.
authors.forename: Philip
authors.initials: P
authors.lastname: Santangelo
authors.affiliation: Department of Biostatistics, Central Institute of Mental Health Mannheim.
authors.forename: Iris
authors.initials: I
authors.lastname: Reinhard
authors.affiliation: Psychosomatic Clinic St. Franziska-Stift.
authors.forename: Lutz
authors.initials: L
authors.lastname: Mussgay
authors.affiliation: Department of Psychology and Sports Sciences, Johann Wolfgang Goethe University.
authors.forename: Regina
authors.initials: R
authors.lastname: Steil
authors.affiliation: Statlab, Institute for Applied Mathematics, University of Heidelberg.
authors.forename: Günther
authors.initials: G
authors.lastname: Sawitzki
authors.affiliation: Klein, Department of Child and Adolescent Psychiatry and Psychotherapy, Freiburg University.
authors.forename: Christoph
authors.initials: C
authors.lastname: Klein
authors.affiliation: Department of Psychological Sciences, University of Missouri-Columbia.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Trull
authors.affiliation: Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University.
authors.forename: Martin
authors.initials: M
authors.lastname: Bohus
authors.affiliation: Department of Sport and Sport Science, Karlsruhe Institute of Technology.
authors.forename: Ulrich W
authors.initials: UW
authors.lastname: Ebner-Priemer
mesh_terms: D000293:Adolescent; D000328:Adult; D000339:Affect; D001883:Borderline Personality Disorder / Q000523:psychology*; D052018:Bulimia Nervosa / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D013313:Stress Disorders, Post-Traumatic / Q000523:psychology*; D055815:Young Adult