Self-harm

Overview

Self-harm is an intentional act of self-injury or self-poisoning, irrespective of motivation. It does not necessarily carry suicidal intent, but is one of the strongest predictors of completed suicide.

Investigations

•Paracetamol and salicylate levels - mandatory in any self-poisoning, even if not declared; paracetamol toxicity may be clinically silent in first 24 hours

•FBC, U&Es, LFTs, clotting, blood glucose - baseline in overdose or significant injury

•12-lead ECG - especially in tricyclic antidepressant or cardiotoxic overdose (QRS widening, prolonged QTc)

•Wound assessment - depth, tendon, nerve, or vascular involvement

•Psychosocial assessment by mental health professional - risk of recurrence, strengths, vulnerabilities

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Always check paracetamol and salicylate levels in any self-poisoning, regardless of what the patient reports. Co-ingestion is common and paracetamol toxicity is treatable if caught early - missing it can be fatal.

Management

•Treat underlying psychiatric conditions (e.g. depression, anxiety) appropriately

•Dialectical behaviour therapy (DBT) - strongest evidence base, particularly for emotionally unstable personality disorder

•Collaborative safety plan, clear follow-up with named contact, and written crisis information before discharge

•Notify GP; refer to community mental health team where indicated

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Employment is a protective factor against suicide - being in work reduces risk. Being married or in a stable relationship is also protective. These are common exam distractors presented as risk factors.

Key epidemiology

•Self-harm more common in women (1 in 4 women vs 1 in 10 men aged 16-24); peak age women 16-24, men 25-34

•Completed suicide ~3x more common in men (17 vs 5.4 per 100,000); highest rates in 45-49 age group

•Men use more lethal methods (hanging, firearms); women more commonly use cutting or self-poisoning - explains the paradox of more self-harm in women but more deaths in men

Risk factors for suicide

•Previous self-harm or suicide attempts - the strongest single predictor

•Escalating frequency or severity of self-harm episodes

•Expressed suicidal intent or hopelessness

•Making plans - writing a note, giving away possessions, researching methods

•Impulsivity and poor distress tolerance

•Feelings of being a burden to others

•Male sex, older age, physical health comorbidities

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Self-harm is sometimes dismissed as 'attention-seeking' and perceived as low risk. Any history of deliberate self-harm - including 'superficial' cutting - significantly increases the risk of completed suicide. Never minimise it.

Protective factors

Protective factors (reduce suicide risk)

Strong social support

Being married or in a stable relationship

Employment - being in work is protective

Sense of responsibility to others (e.g. dependent children)

Engagement with mental health services

Resilience and coping strategies