What is the approach to assessing personality disorders, including definition, differential diagnosis, history, physical examination, investigations, empiric treatment, and indications for referral?

Approach to Assessment of Personality Disorders

Definition

Personality disorders are characterized by pervasive problems in functioning of aspects of the self and/or interpersonal dysfunction that cause significant impairment in social and occupational functioning, with the ICD-11 now using a dimensional model that assesses severity (mild, moderate, severe) and specifies maladaptive personality traits rather than discrete categorical diagnoses. 1, 2

• The DSM-5 alternative model uses a dimensional-categorical hybrid approach assessing impairments in personality functioning and pathological personality traits across five domains: Negative Affectivity, Detachment, Antagonism, Disinhibition, and Psychoticism 1, 2
• The ICD-11 allows specification of traits including negative affectivity, detachment, dissociality, disinhibition, anankastia, and borderline pattern 1, 2
• These disorders involve inflexible maladaptive traits that result in inability to cope with environmental pressure 3

Differential Diagnosis

Primary Psychiatric Disorders to Exclude

• Major depressive disorder, bipolar disorder, anxiety disorders, and psychotic disorders must be ruled out first, as these may present with personality changes but represent distinct conditions requiring different treatment approaches 4
• Borderline personality disorder's dissociative symptoms (derealization, depersonalization) should not be mistaken for primary psychotic disorder, as BPD lacks formal thought disorder, disorganized thought, and disorganized speech 5
• Substance use disorders can mimic personality pathology and should be assessed 2

Distinguishing Between Personality Disorder Types

• Borderline personality disorder is distinguished by repeated self-injury and suicidality (11-44% attempt suicide), unstable self-concept, dissociative symptoms, and chaotic relationships with fear of abandonment, whereas histrionic personality disorder centers on attention-seeking without self-destructive behaviors 5
• Borderline patients exhibit idealization-devaluation patterns where they rapidly alternate between viewing others as entirely "good" or entirely "bad" 5
• The presence of suicidality and self-harm definitively points toward borderline personality disorder, not histrionic 5

Medical Conditions

• Personality change in older patients suggests organic disease and requires neurological workup 3
• Traumatic brain injury, dementia, and other neurological conditions can present with personality changes 3

History

Character of Presentation

• Assess who initiated the consultation—patients with personality disorders often present at others' insistence rather than self-referral, and whether the patient is over- or under-emphasizing disability provides diagnostic information independent of patient insight 2
• Lack of insight is a core feature of personality disorders, not an exclusionary criterion 2
• Onset typically occurs in early adulthood with pervasive patterns across multiple contexts 2
• Inflexible nature results in inability to develop alternative behavioral repertoires 3

Red Flags

• Repeated suicide attempts and non-lethal self-injury (hallmark of borderline personality disorder) 2, 5
• Pervasive pattern of impulsivity strongly associated with suicidality 2
• Unstable mood and interpersonal relationships 2
• Varying self-concept that oscillates between grandiosity and worthlessness 2, 5
• Chaotic relationships with alternating idealization and devaluation 5
• Self-damaging behaviors (substance abuse, reckless driving, binge eating, unsafe sex) 2
• Treatment ruptures, discontinuation, reversals, and failures are common 6

Risk Factors

• Complex interaction of genetic predisposition and environmental factors, particularly adverse childhood experiences 2
• Family psychopathology including history of suicidal behavior, bipolar illness, physical/sexual abuse, or substance abuse 2
• Premature mortality is associated with personality disorders 2

Essential Historical Elements

• Gather information from multiple sources using varied developmentally sensitive techniques, as self-reporting is unreliable due to impaired insight 2, 4
• Confirmation from multiple informants is necessary due to discrepancies 2, 5
• Detailed and carefully taken history focusing on longitudinal patterns, not isolated incidents 4, 7
• Specific inquiry about suicide attempts, self-injury, identity confusion, and dissociative experiences 5
• Systematic history revealing recurring patterns across time and contexts 7
• Assessment of functioning in work, relationships, and self-concept 1, 2

Physical Examination (Focused)

• Examine for evidence of self-injury including cutting scars, burns, or other self-inflicted wounds, particularly on forearms, thighs, and abdomen 2
• Assess for signs of substance abuse (track marks, nasal septum damage, hepatomegaly) 2
• Neurological examination to exclude organic causes, especially in older patients or those with acute personality changes 3
• Mental status examination documenting affect stability, thought process, and presence of dissociative symptoms 5

Investigations

Structured Assessment Tools

• Use structured interviews rather than self-report questionnaires, as self-report psychiatric scales have minimal usefulness in personality disorders due to impaired insight 2, 7
• Structured interviews yield higher diagnostic concordance than self-report questionnaires (median kappa = 0.25 for agreement between methods) 7
• Behavioral scales capturing lack of insight improve early differentiation 2

Laboratory and Imaging

• No specific laboratory tests diagnose personality disorders, but investigations should exclude medical mimics 3
• Thyroid function tests, complete blood count, comprehensive metabolic panel to exclude metabolic causes 3
• Urine drug screen to assess substance use 2
• Brain imaging (CT or MRI) if organic etiology suspected, particularly in older patients or acute changes 3

Expected Findings

• Laboratory and imaging studies are typically normal in primary personality disorders 3
• Abnormal findings suggest alternative diagnosis requiring further workup 3

Empiric Treatment

Psychotherapy (First-Line)

• Evidence-based psychotherapeutic approaches are the primary treatment: Dialectical Behavior Therapy (DBT), Cognitive Behavioral Therapy (CBT), Mentalization-Based Treatment, Schema Therapy, and Transference-Focused Psychotherapy 2
• Initial psychotherapeutic case formulation is essential to enhance alliance and adherence 4
• Treatment focuses on developing healthier behavioral responses to stress 3

Pharmacotherapy (Adjunctive)

• Pharmacotherapy targets specific symptoms rather than the personality disorder itself and should not be first-line monotherapy 2
• Mood stabilizers for emotional dysregulation 2
• Antipsychotics for cognitive-perceptual symptoms 2
• Antidepressants for comorbid depression or anxiety 2
• Anxiolytics (use cautiously given impulsivity and substance abuse risk) 2

Treatment of Comorbidities

• Psychiatric comorbidities should be treated first if severe, as they may complicate personality disorder management 4

Indications to Refer

Immediate Psychiatric Referral

• Active suicidality or recent suicide attempt requires immediate psychiatric evaluation 2, 5
• Acute self-harm behavior 2, 5
• Severe functional impairment preventing self-care 2
• Psychotic symptoms requiring differentiation from primary psychotic disorder 5

Routine Specialty Referral

• All confirmed personality disorder diagnoses benefit from specialized psychotherapy by trained mental health professionals 2, 4
• Treatment ruptures or failures in primary care setting 6
• Need for structured psychotherapy (DBT, mentalization-based treatment, etc.) 2
• Complex comorbidities requiring integrated psychiatric care 4
• Diagnostic uncertainty requiring structured assessment 4, 7

Critical Pitfalls

Assessment Pitfalls

• Do not dismiss the diagnosis because the patient lacks insight—lack of insight is a core feature of personality disorders, not evidence against the diagnosis 2
• Do not rely solely on patient self-report; always obtain collateral information from multiple sources 2, 5, 7
• Do not assess during acute psychiatric episodes; personality assessment requires evaluation after symptom stabilization to distinguish state from trait 8, 7
• Do not mistake borderline personality disorder's dissociative symptoms for primary psychosis 5
• Do not use self-report questionnaires as primary diagnostic tools; structured interviews are superior 7
• Do not diagnose based on isolated incidents; personality disorders require pervasive, longstanding patterns across contexts 7

Treatment Pitfalls

• Do not use pharmacotherapy as monotherapy; psychotherapy is the primary evidence-based treatment 2
• Do not prescribe anxiolytics liberally given high risk of substance abuse and impulsivity 2
• Do not treat personality disorder before addressing severe comorbid psychiatric conditions 4
• Do not expect rapid improvement; treatment ruptures and discontinuation are common and should be anticipated 6
• Do not fail to establish initial psychotherapeutic case formulation, as this enhances alliance and adherence 4

Diagnostic Pitfalls

• Do not overlook organic causes in older patients or those with acute personality changes 3
• Do not confuse histrionic and borderline personality disorders; suicidality and self-harm definitively indicate borderline 5
• Do not interpret informant discrepancies as invalidating the diagnosis; expect and evaluate these systematically 9