Self-harm refers to an intentional act of self-poisoning or self-injury, irrespective of the motivation or apparent purpose of the act (NICE, 2004). It is now widely accepted that people who self-harm are expressing their emotional turmoil by committing the act.
Self-injury usually involves cutting, but can also include burning, hanging, stabbing, shooting, swallowing or inserting objects, and jumping in a way that can cause injury.
Common methods of self-poisoning include abusing prescribed or over-the-counter medications, or less commonly illicit drugs, other household substances or plant material.
There are two NICE guidelines concerned with the management of self-harm (NICE, 2004; NICE 2011), both of which were mostly developed from the expert opinion of the guideline development group, following narrative reviews of the evidence, where such were available.
The evidence is pretty thin on the ground in this field, so it’s good to see an updated systematic review from the Cochrane Depression, Anxiety and Neurosis Group, which was published on Monday of this week. This is a refresh of a review last updated in 1999, which covered pharmacological and psychosocial treatments for deliberate self-harm. The reviewers have split the pharmacological and psychosocial interventions this time around and will publish a separate review on the psychosocial treatments soon.
The main objective of this new review was to find all randomised controlled trials (RCTs) of drugs or dietary supplements for self-harm in adults, and to conduct a meta-analyses that compared the effects of specific treatments with comparison types of treatment (e.g. placebo/alternative drug treatments).
Comorbidity with other mental health conditions
There is a high prevalence of other mental health conditions (such as depression, anxiety disorders and borderline personality disorder) in people who engage in self-harm.
So, it’s reasonable to consider what impact some existing treatments (like the ones listed below) may have on the recurrence of self-harm:
- antidepressants(used in the same dose range as they are for depression) are often considered, and SSRIs are preferred for their lower case fatality indices (Hawton et al, 2010);
- low dose antipsychotics may be used to reduce heightened arousal, which is one risk factor for self-harm may be (Battaglia 1999);
- mood stabilisers have specific benefits for patients with bipolar disorder or unipolar depression, and might be anticipated to reduce suicidal behaviour;
- natural products (especially dietary supplementation of omega-3 fatty acids) might also be anticipated to have a reducing effect on suicidal behaviour.
The reviewers carried out a very comprehensive and systematic search and (after imposing their stringent selection criteria) ended up with 7 trials including a total of 546 patients. The trials were independently selected and appraised for quality using the GRADE approach.
A meta-analysis was only possible for one of the treatments covered by the review: newer antidepressants (Nomifensine, Mianserin and Paroxetine) on repetition of self-harm at the last follow-up. This analysis pooled the trial data from 3 studies (243 patients in total) and used a random-effects model.
The authors found no significant treatment effect on repetition of self-harm for:
- newer generation antidepressants (Odds ratio (OR) 0.76, 95% Confidence interval (CI) 0.42 to 1.36)
- low-dose fluphenazine (OR 1.51, 95% CI 0.50 to 4.58)
- mood stabilisers (OR 0.99, 95% CI 0.33 to 2.95)
- natural products (OR 1.33, 95% CI 0.38 to 4.62)
A significant reduction in self-harm repetition was found in a single trial of the antipsychotic flupenthixol (OR 0.09, 95% CI 0.02 to 0.50).
The quality of all the trials included in the review, according to the GRADE criteria, was low to very low.
The authors concluded:
Given the low or very low quality of the available evidence, and the small number of trials identified, it is not possible to make firm conclusions regarding pharmacological interventions in SH patients. More and larger trials of pharmacotherapy are required.
This well conducted systematic review shows that there is little evidence to support the use of either pharmacological or natural products for the treatment of self-harm. However, as the authors note, very few trials that have been conducted, and those that have are small and low quality, which means that possible beneficial effects of some therapies cannot be ruled out. Furthermore, in view of an indicated positive benefit for flupenthixol in an early small trial of low quality, future studies might include evaluation of newer atypical antipsychotics. Other research could include evaluation of combined pharmacotherapy and psychological treatment.
It’s worth noting that a separate Cochrane review on psychosocial interventions is also planned, so we can only hope that clearer evidence is produced by that piece of work, to support this group of patients.
Hawton K, Witt KG, Taylor Salisbury TL, Arensman E, Gunnell D, Hazell P, Townsend E, van Heeringen K. Pharmacological interventions for self-harm in adults. Cochrane Database of Systematic Reviews 2015, Issue 7. Art. No.: CD011777. DOI: 10.1002/14651858.CD011777.
Battaglia J, Wolff TK, Wagner-Johnson DS, Rush AJ, Carmody TJ, Basco MR. Structured diagnostic assessment and depot fluphenazine treatment of multiple suicide attempters in the emergency department. International Clinical Psychopharmacology 1999;14:361–72. [Abstract]
Hawton K, Bergen H, Simkin H, Cooper K, Waters K, Gunnell D, et al. (2010) Toxicity of antidepressants: Rates of suicide relative to prescribing and non-fatal overdose. British Journal of Psychiatry 2010;196:354-8.
National Collaborating Centre for Mental Health (2004) Self-harm. The short-term physical and psychological management and secondary prevention of self-harm in primary and secondary care (full NICE guideline). Clinical guideline 16. The British Psychological Society and the Royal College of Psychiatrists. [Free Full-text]
National Collaborating Centre for Mental Health (2011) Self harm. The NICE guideline on longer-term management (full NICE guideline). Clinical guideline 133. National Institute for Health and Care Excellence. [Free Full-text]