Individuals who show nervous or risky behavior are at least 50 percent more likely to commit suicide if they fall into a state of depression, according to a new study. The findings may lead to changes in clinical practice in the care of patients affected with depression, as they reveal factors which confer major risk of suicide attempts.

The BRIDGE-II-MIX study is a major international study looking at depression and suicide. The researchers evaluated 2811 patients suffering from depression, of whom 628 had already attempted suicide.

Each patient was interviewed by a psychiatrist as if it were a standard evaluation of a mentally-ill patient. The parameters studied included previous suicide attempts, family history, current and previous treatment, patients' clinical presentation, how they scored on the standard Global Assessment of Functioning scale, and other parameters.

The study looked especially at the characteristics and behaviours of those who had attempted suicide, and compared these to depressed patients who had not attempted suicide. They found that certain patterns recur before suicide attempts.

Study author Dr. Dina Popovic said:

“We found that “depressive mixed states” often preceded suicide attempts. A depressive mixed state is where a patient is depressed, but also has symptoms of “excitation”, or mania. We found this significantly more in patients who had previously attempted suicide, than those who had not. In fact 40% of all the depressed patients who attempted suicide had a “mixed episode” rather than just depression. All the patients who suffer from mixed depression are at much higher risk of suicide.

We also found that the standard DSM criteria identified 12% of patients at showing mixed states, whereas our methods showed 40% of at-risk patients. This means that the standard methods are missing a lot of patients at risk of suicide."

Statistics for suicide are alarming

According to the WHO, more than 800,000 people commit suicide every year, with perhaps 20 times that number attempting suicide. Suicide is one of the leading causes of death in the young. For example, in the UK it is the leading cause of death in men under 35.

Effective means of suicide prevention are urgently needed.

The researchers also found that if a depressed patient presents any of the following symptoms:

  • risky behaviour (e.g. reckless driving, promiscuous behaviour)

  • psychomotor agitation (pacing around a room, wringing one’s hands, pulling off clothing and putting it back on and other similar actions)

  • impulsivity (acting on a whim, displaying behaviour characterized by little or no forethought, reflection, or consideration of the consequences),

then their risk of attempting suicide is at least 50% higher.

Dr Popovic says:

“In our opinion, assessing these symptoms in every depressed patient we see is extremely important, and has immense therapeutical implications. Most of these symptoms will not be spontaneously referred by the patient, the clinician needs to inquire directly, and many clinicians may not be aware of the importance of looking at these symptoms before deciding to treat depressed patients.

This is an important message for all clinicians, from the GPs who see depressed patients and may not pay enough attention to these symptoms, which are not always reported spontaneously by the patients, through to secondary and tertiary level clinicians. In highly specialized tertiary centres, clinicians working with bipolar patients are usually more aware of this, but that practice needs to extent to all levels.

The strength of this study is that it’s not a clinical trial, with ideal patients - it’s a big study, from the real world”.

Popovic D, Vieta E, Azorin J, Bowden C, Young A, Perugi G. Suicidal behaviour in major depressive episode: evidence from the BRIDGE-II-MIX study. European College of Neuropsychopharmacology (ECNP) Conference

Illustration: Nanette Hoogslag, Wellcome Images

For future updates, subscribe via Newsletter here or Twitter