2 Neuroscience2.11 Integrated neurobiology of syndromes and states
2.11.11 Self harm and suicidality
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Written by Resident Doctor Committee · Published
Four outcomes
Behaviour | Definition |
|---|---|
Non-suicidal self-harm | Deliberate injury without intent to die |
Suicidal ideation | Passive death wishes through to active plans |
Suicide attempt | Self-injury with some intent to die |
Death by suicide | Fatal suicidal act |
Epidemiology and diagnosis
UK suicide rates per 100,000 now peak in men aged roughly 45 to 54.
Men die by suicide at about three times the female rate.
Adjustment disorder is the diagnosis most often made at routine psychiatric assessment after self-harm in the emergency department.
Depression is commoner only on structured research interview.
Stress-diathesis model
Mann's stress-diathesis model combines acute stressors with pre-existing vulnerability.
Component | Examples |
|---|---|
Acute precipitant | Loss, humiliation, entrapment, financial crisis |
Psychiatric state | Depression, psychosis, intoxication, insomnia |
Developmental adversity | Maltreatment, neglect, bullying |
Trait vulnerability | Impulsivity, aggression, rigidity, pessimism |
Serotonin
Low cerebrospinal fluid (CSF) 5-HIAA, the main serotonin metabolite, marks reduced central serotonin turnover.
It is associated with suicide attempts, especially violent or lethal ones.
It also occurs with impulsive aggression, so it is neither specific to suicide nor a measure of intent.
Risk prediction
Suicide is rare, so any test has a low positive predictive value and produces many false positives.
No biological test or scale determines or excludes individual risk.
The National Institute for Health and Care Excellence (NICE) advises against prediction scales or low, medium and high categories to decide treatment or discharge.
Clinicians instead build a collaborative formulation and safety plan, including access to means.