CASC Knowledge Essentials04 · Personality difficulties, self-harm and suicide
04 · Personality difficulties, self-harm and suicide
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Written by Resident Doctor Committee · Published
4.1 Personality disorder: an enduring pattern
Personality disorder involves persistent difficulty in self-functioning, relationships or both, across situations, with distress or impairment. One crisis, disagreement or difficult interaction with staff is insufficient.
ICD-11 grades severity first: mild, moderate or severe. It then adds trait qualifiers and, where appropriate, a borderline-pattern qualifier. The pattern is usually established over at least two years, interpreted in developmental and cultural context.
Trait | Central feature |
|---|---|
Negative affectivity | Intense/frequent negative emotions and difficulty recovering |
Detachment | Emotional and interpersonal distance; reduced interest in closeness |
Dissociality | Disregard for others' rights/feelings; strong self-centredness |
Disinhibition | Impulsive action without enough consideration of consequences |
Anankastia | Rigid perfectionism, control and rule-bound behaviour |
Traits describe the pattern, not its cause or inevitable outcome. Older terms such as emotionally unstable personality disorder may appear in records and treatment guidance; current ICD-11 diagnoses use severity, traits and the optional borderline pattern.
4.2 The borderline pattern
Unstable relationships, self-image and affect, with impulsivity. ICD-11's borderline-pattern specifier describes five or more of nine features.
Domain | Features |
|---|---|
Relationships | Desperate avoidance of real/perceived abandonment; intense relationships shifting between idealisation and devaluation |
Self | Unstable identity; chronic emptiness |
Emotion | Marked mood reactivity; intense or poorly controlled anger |
Behaviour | Rash self-damaging behaviour; recurrent self-harm |
Stress response | Transient dissociation or psychotic-like experiences during intense arousal |
Self-harm is not compulsory for diagnosis. Mood reactivity can last hours and sometimes days. Establish the longitudinal pattern and revisit uncertain diagnoses outside the crisis.
Dissociation may feel like bodily detachment, numbing or unreality. Voices and suspiciousness still need proper characterisation: a personality diagnosis does not exclude persistent psychosis, mania, substance effects or trauma-related illness.
Adversity, temperament and later experience can contribute. Childhood trauma is neither necessary nor sufficient; the diagnosis does not prove abuse occurred.
4.3 Distinguishing bipolar disorder and complex PTSD
Alternative | Useful distinction | Remember |
|---|---|---|
Bipolar disorder | Sustained mood/energy change with characteristic sleep/activity changes; borderline shifts often follow interpersonal events | Both can coexist; trigger and duration alone do not settle it. |
Complex PTSD | Requires PTSD plus problems with regulation, self-concept and relationships | Substantial overlap with borderline patterns is possible. |
Depression | An episode or persistent mood syndrome rather than enduring cross-situational dysfunction | Depression may amplify personality difficulties and needs treatment. |
ADHD | Requires a developmental history of attention and/or hyperactive-impulsive symptoms | Adult impulsivity alone is insufficient. |
A few distressed hours after an argument is not rapid-cycling bipolar disorder. A borderline diagnosis equally does not rule out a later manic or hypomanic episode.
4.4 What treatment is intended to change
Structured therapy improves regulation, relationships, self-understanding and functioning while reducing dangerous coping. Self-harm may improve before loneliness or occupational difficulties. Enduring does not mean untreatable.
NICE recommends considering comprehensive DBT for women with borderline personality disorder when recurrent self-harm is a priority. This reflects the evidence reviewed, not an intrinsic restriction by gender. MBT, CAT and schema-informed programmes are other approaches, with differing evidence and availability.
DBT: acceptance and change
A response can be understandable and still need changing. DBT combines validation with safer ways of responding.
Part of DBT | What to know |
|---|---|
Programme | Individual therapy, skills group, between-session coaching, therapist consultation team |
Four skills | Mindfulness, distress tolerance, emotion regulation, interpersonal effectiveness |
Target hierarchy | Life-threatening behaviour → therapy-interfering behaviour → quality-of-life problems |
Tools | Diary cards and chain analysis linking vulnerabilities, triggers, emotions, urges and consequences |
Coaching helps skills transfer into daily life within agreed boundaries; it is not unrestricted emergency cover. A skills group alone is not the full programme.
Mentalisation and other approaches
Mentalisation means understanding behaviour through mental states while accepting uncertainty about other minds. Under attachment stress, “They have not replied” may become “They are rejecting me”. MBT restores curiosity and alternative interpretations before action.
CAT maps recurring relational patterns and exits from them. Schema therapy addresses enduring patterns of meaning and coping shaped by developmental experience.
Medication and hospital care
Do not prescribe specifically for borderline personality disorder or its core behaviours, including recurrent self-harm or transient psychotic symptoms. Treat a separately established comorbid disorder. Polypharmacy can add sedation, dependence, metabolic harm and overdose access without changing the underlying pattern.
An occasional crisis sedative should have a defined target and usually last no more than one week. Admission is appropriate when significant risk cannot be managed elsewhere, with a clear purpose and expected duration. Neither automatic admission nor blanket exclusion by diagnosis is appropriate.
4.5 What self-harm means
NICE defines self-harm as intentional poisoning or injury irrespective of apparent purpose. Functions include reducing emotional overload, countering numbness, self-punishment, communicating distress and attempting death. Functions can coexist or change.
Non-suicidal self-injury is not a suicide attempt, but one episode without suicidal intent does not exclude future suicide. “Attention seeking” is not a sufficient explanation; wanting a response and being in danger can coexist.
Keep three questions separate: intent to die, expected lethality and actual medical severity. A person can intend death but misunderstand a method, or sustain serious injury with ambivalent intent. Rescue does not erase the original intent.
4.6 Understanding suicidal intent and the current state
Planning, preparation, avoiding discovery and arrangements anticipating death can indicate stronger intent. Impulsive does not mean safe, particularly with intoxication, available means or rapidly changing emotion.
Information | Meaning |
|---|---|
Intent during the act | Desired and expected outcome at that time |
Help-seeking/rescue | Possible ambivalence or changed intent; context matters |
Response to survival | Relief, uncertainty or regret describes the present state, not a standalone prediction |
Current syndrome | Depression, psychosis, agitation, intoxication or withdrawal may drive danger |
Changed pattern | Escalation, new stressors or a different method may outweigh familiarity with past contacts |
Means/upcoming events | Access, losses and transitions affect the near future |
A passive death wish may express severe hopelessness despite no plan. Children or other named protective factors only help if meaningful, available and likely to influence current behaviour.
Formulate needs and mechanisms; do not calculate a predicted suicide. NICE advises against risk scales or global low/medium/high ratings for predicting repetition or determining treatment/discharge. Risk changes with the clinical state.
4.7 Conditions to identify after self-harm
Consider depression, including psychotic guilt/nihilism; bipolar mixed symptoms combining despair and activation; alcohol-related disinhibition or withdrawal; trauma, abuse, pain, loss and practical adversity.
The act does not itself diagnose depression, personality disorder or adjustment disorder. An obvious precipitant does not exclude severe mental illness, and an existing psychiatric diagnosis does not explain away an acute medical problem.
Psychosocial assessment begins alongside physical care. Do not wait solely for medical treatment to finish or a specified alcohol concentration. If impairment prevents meaningful participation, provide support and repeat review until assessment becomes possible.
4.8 Treatment after self-harm: what is evidence-based?
For adults, offer a CBT-informed intervention tailored to self-harm, including problem solving, typically 4–10 sessions, adjusted to need. Treatment should not require a particular diagnostic label.
No medicine is prescribed solely to prevent self-harm. Treat underlying disorders and consider overdose toxicity, interactions, quantities supplied and other household medicines. Relative SSRI safety does not make overdose harmless.
A safety plan links warning signs, coping responses, useful contacts and reduced access to lethal means. It must fit the person's circumstances and cognitive state. It is neither a guarantee nor a “no-suicide contract”.
With ongoing safety concerns, arrange initial aftercare within 48 hours of psychosocial assessment. Urgent treatment should not wait for that deadline. Discharge and other transitions may remove support before the underlying difficulty improves.
Capacity and compulsory powers require their own decision-specific legal assessment. Neither self-harm, diagnosis nor a wish to leave settles them.