Mood disorders include schizoaffective, dysthymia, rapid cycling, unipolar and bipolar disorders. People with mood disorders have a 30 times higher risk of suicide than the general population.

Recent Mental Elf blogs have summarised the data on suicide risk and bipolar disorder, and shown that one key treatment is lithium which appears to have a robust evidence base in the long term treatment of bipolar disorder.

A previous systematic review published in 2005 concluded that lithium was effective in reducing suicide (Cipriani et al, 2005). This review has now been updated and published in the BMJ.

Methods

The authors conducted a systematic review and meta-analysis attempting to find all studies published up to January 2013 via a number of databases (Medline, PreMedline, Embase, Cinahl, PsycINFO, LILACS & Cochrane).

The review included all randomised controlled trials (RCTs) of long-term treatment of mood disorders. Long term treatment was defined as more than 12 weeks.

Data on three outcome measures were extracted:

• Suicide events
• Deliberate self harm
• All cause mortality

Results

• 48 trials were identified from the initial 1,491 hits; 16 more trials than the previous review
  • This included 6,674 participants; a 70% increase from the previous review

• Lithium was more effective than placebo in reducing:
  • Suicide (OR 0.13, 95% CI 0.03 to 0.66)
  • All cause mortality (OR 0.38, CI 0.15 to 0.95)
• The effect on deliberate self-harm was less clear
• When lithium was compared with other active drugs, there were no significant differences for either suicide rates, all cause mortality or deliberate self-harm
• In further analysis, lithium was significantly better than anticonvulsants for deliberate self-harm

Conclusions

The authors conclude:

Lithium was associated with a reduced risk of suicide when compared with placebo, and also a reduced risk deliberate self harm when compared with carbamazepine.

A new finding is that lithium reduces the risk of suicide and total deaths in people with unipolar and bipolar depressive disorder.

Discussion

The authors reported a number of limitations of their review. Most importantly were the small sample sizes of the studies included; the nature of low frequency events such as suicide and death; those at most risk are often excluded from drug trials, all of which can influence the treatment effects identified.

Whilst there is evidence supporting the use of lithium, the exact mechanism of action is still unknown.  A number of theories have been suggested which include the reduction of relapse rates, specific anti-suicidal properties, but also reduced impulsivity association with taking lithium.

Whilst lithium appears to remain an effective treatment option there are known concerns about the long-term use of the drug and it’s impact on an individual’s physical health (see the NPSA website for further details of safer lithium therapy).

If you need help

If you need help and support now and you live in the UK or the Republic of Ireland, please call the Samaritans on 116 123.

If you live elsewhere, we recommend finding a local Crisis Centre on the IASP website.

We also highly recommend that you visit the Connecting with People: Staying Safe resource.

Links

Cipriani A, Hawton K, Stockton S, Geddes JR. Lithium in the prevention of suicide in mood disorders: updated systematic review and meta-analysis. BMJ 2013;346:f3646

Cipriani A, Pretty H, Hawton K, Geddes JR. Lithium in the prevention of suicidal behavior and all-cause mortality in patients with mood disorders: a systematic review of randomized trials. Am J Psychiatry. 2005 Oct;162(10):1805-19. [PubMed abstract]

Bipolar disorder: the management of bipolar disorder in adults, children and adolescents, in primary and secondary care (PDF). NICE clinical guideline 38, Jul 2006.

NPSA (National Patient Safety Agency) web page on Safer Lithium Therapy. Last accessed on 1 Oct 2013.