8/10/2019 Suicice Can We Realy Prevent

1/17

Can We Really Predict Suicide?

Prof. Gil Zalsman M.D.Deputy Director, Geha Mental Health Center

Psychiatry DepartmentSackler Faculty of Medicine

Tel Aviv University, Israel&

Chair, National Council for Suicide Prevention, Israel&

Associate Research Scientist

Molecular Imaging and Neuropathology DivisionPsychiatry DepartmentColumbia University

New York, NY

ESSSB15 Tall inn A ug 29 16-18:00 Room A002

http://www.google.co.il/imgres?imgurl=http://www.cortechsolutions.com/getattachment/13ac05cb-6704-4e01-948b-6102c80d2cfa/Timing.aspx&imgrefurl=http://www.cortechsolutions.com/Products/Stimulus-delivery/Stimulus-software/Presentation.aspx&usg=__D7KmnwXXt5axmTcGmv2sRqiclQw=&h=333&w=314&sz=62&hl=iw&start=4&zoom=1&itbs=1&tbnid=w7qQS5BNhcFHfM:&tbnh=119&tbnw=112&prev=/images%3Fq%3Dtiming%26hl%3Diw%26sa%3DG%26gbv%3D2%26tbs%3Disch:1http://www.google.co.il/imgres?imgurl=http://www.cortechsolutions.com/getattachment/13ac05cb-6704-4e01-948b-6102c80d2cfa/Timing.aspx&imgrefurl=http://www.cortechsolutions.com/Products/Stimulus-delivery/Stimulus-software/Presentation.aspx&usg=__D7KmnwXXt5axmTcGmv2sRqiclQw=&h=333&w=314&sz=62&hl=iw&start=4&zoom=1&itbs=1&tbnid=w7qQS5BNhcFHfM:&tbnh=119&tbnw=112&prev=/images%3Fq%3Dtiming%26hl%3Diw%26sa%3DG%26gbv%3D2%26tbs%3Disch:1

8/10/2019 Suicice Can We Realy Prevent

2/17

8/10/2019 Suicice Can We Realy Prevent

3/17

Prediction in medicine

Perform benefit/risk assessments of theinterventions and intervene only when benefitsunequivocally exceed the risks .

The scope of prediction (diagnosis) is to limitthe intervention to those affected by thecondition , thus improving the benefit/risk ratio.

If you can predict and you didnt - you areresponsible for the results

8/10/2019 Suicice Can We Realy Prevent

4/17

The Prediction Paradox

We teach risk assessment

We try to control riskfactors

BUT we can not predictbetter than flipping a coin

8/10/2019 Suicice Can We Realy Prevent

5/17

8/10/2019 Suicice Can We Realy Prevent

6/17

Confused?

8/10/2019 Suicice Can We Realy Prevent

7/17

Stadium with 100 K citizens ofTallinn

17 will commit suicide Data from

8/10/2019 Suicice Can We Realy Prevent

8/17

Stadium of 100 K males in Tallinn

32 will commit suicide

8/10/2019 Suicice Can We Realy Prevent

9/17

Stadium of 100 K depressed inTallinn

5000 will commit suicide

8/10/2019 Suicice Can We Realy Prevent

10/17

Stadium of 100 K depressed inTallinn

Is this guy is one of the 5000?

8/10/2019 Suicice Can We Realy Prevent

11/17

1 . Suicide is a high impact, low probabilityevent2. The prediction power of the demographic and

phenomenological variables is very low3. No data exists to support prediction orpreventive intervention at the individual level*(which is what doctors care about)

4 . Therefore the clinician cannot be heldresponsible

Limiting availability of fire arms and gate gatekeeper educationhas had moderate effects at the population level (Mann et al., 2005)

My Message

8/10/2019 Suicice Can We Realy Prevent

12/17

Game Theory

"the study of mathematical models of conflictand cooperation between intelligent rationaldecision- makers(Mayerson 1991)

http://www.google.co.il/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&docid=4K_8T1T2ZgcvEM&tbnid=JxuUbtrk0Nm4SM:&ved=0CAUQjRw&url=http%3A%2F%2Fwww.theatlantic.com%2Fpolitics%2Farchive%2F2013%2F01%2Fhow-game-theory-explains-washingtons-horrible-gridlock%2F267142%2F&ei=-en8U4OMHMHvPIHfgLAN&bvm=bv.74035653,d.bGE&psig=AFQjCNGOfjL89PU8vkeZpiaQJeISXkxd7A&ust=1409170052350031

8/10/2019 Suicice Can We Realy Prevent

13/17

Irrational prediction

Prof. Daniel Kahnman2002 Nobel price winner ineconomics

Prof. Dan ArielyAuthor of

predictably irrational

Behavioral economics

8/10/2019 Suicice Can We Realy Prevent

14/17

Biases and difficulties in risk-benefit assessment

Event available in the recent memory Attributing causality to natural course of disease

or to randomness

Ignoring low base rate Overweight small probabilities and underweight

moderate and large ones.

Statistical illiteracy Loss aversion The tendency to personalize and be influenced by

anecdotes

8/10/2019 Suicice Can We Realy Prevent

15/17

At the individual level, are characteristics (risk factors)for suicide consistent and reliable?

low IQ

high impulsivity active psychosis low socio-economic status unemployment increases risk

Young age

high IQ

low impulsivity remission of psychosis high socio-economic status unemployment decreases risk

Old age

*Depression and previous attempts (common in clinical sample)(Pokorny 1983 Arch Gen Psychiatry; Hunt et al 2007 Psychological Medicine 37; 831-837; Valenstein et al 2008; Bowers et al 2010;Journal of Affective disorders Bolton et al 2012 J Clin Australasian Psychiatry; Peuskens et al 1997;Fenton 2000; Madsen et al2012 J Clin Psychiatry Osborn et al 2007 Schizophrenia research ; Hunt et al 2007; Agerbo 2005).

8/10/2019 Suicice Can We Realy Prevent

16/17

Why is suicide so hard to predict?A rare event (low base rate) is always hard to predict

It is easier to predict how many days it willrain in May of 2015 in London than in Dubai

Buying 10 lottery tickets rather than 1 willincrease the chances of winning the lotteryX10, yet very low chance to win.

It is easy to predict who, out of 100psychiatric patients who are very high-risk forsuicide, will not commit suicide than who

will.

8/10/2019 Suicice Can We Realy Prevent

17/17