Risk assessment in OCD

This is a set of recommendations for how to think about assessing risk in OCD. It combines what is known (from the published literature) about whether people with OCD act on their obsessions, and tries to provide a framework for assessment that can help answer some of the important questions that clinicians might face. Various differential diagnoses are considered along the way. The ultimate message(s) are:

1. Don't assume anything.
2. Nothing replaces good and experienced clinical assessment.

Introduction

Clinicians are commonly asked a simple question: "This person has intrusive and recurrent thoughts about harming people they know/ inappropriate sexual thoughts. Should we be worried and do we need additional safeguarding?" Another common situation is when mothers with OCD have intrusive and unpleasant thoughts about harming their child. Healthcare services often become anxious in such situations and there are often occasions when safeguarding is implemented even when the risk from such obsessions is not present.

In a study looking at how psychiatrists approached the management of descriptions of filicidal obsessions, Booth et al (2014) reported that only two thirds (62%) considered OCD among the differential diagnosis, and about the same proportion were prepared to consider involuntary admission (60%) and reports to child welfare authorities (68%).

A good place to start is a review of such issues by David Veale and colleagues from 2009. They said: "...there are no recorded cases of a person with OCD carrying out their obsession." (Veale, 2009)

Is there evidence that people with OCD act on their thoughts?

Essentially, no. There is no published report of someone with diagnosed OCD acting on their feared thought. This doesn't, of course, include people with OCD who act out for other reasons (for example, aggression due to ASD), or because they are drunk, but in such cases the actual behaviour is not clearly linked to underlying obsessions.

So far, we have only found one published case where it is suggested that someone with OCD acted on obsessions (Finkenbine, 2000), but the case is rather bizarre and involved attacking someone whose eyes reminding him of a tree frog's that he had been 'obsessing' about. All his other presumed OCD-related symptoms were about contamination. This case was reported in a letter to a journal and descriptions of the diagnosis and other symptoms make it hard to conclude that OCD was the primary mental disorder associated with the individual's violent acts.

Although there are descriptions of patients with comorbid ASD and OCD being aggressive, the primary driver for the aggression is invariably the ASD and other experiences (such as a history of bullying), and the violence is often employed as a strategy to overcome unpleasant thoughts (Edwards & Higham, 2020).

Harm obsessions towards children

In a small case series of mothers with OCD who had aggressive obsessions involving their children (N=7), none of them acted on their obsessions to harm their children. Worryingly, these thoughts interfered with normal mother-child relationships (Arnold, 1999), probably because mothers were avoidant of situations that may trigger such thoughts.

A review of mothers who kill their children did not identify true obsessions (or OCD) as being associated with 'maternal filicide'. Instead, the kinds of thoughts associated with harm to children were related to other factors such as: psychotic symptoms; delirium; severe depression; and mania (Hatters Friedman, 2007).

Differentiating sexual obsessions from paedophilia

Another important area where obsessions can be difficult to untangle from other types of thoughts is intrusive sexual thoughts.

References

Booth, B. D., Friedman, S. H., Curry, S., et al (2014) Obsessions of Child Murder: Underrecognized Manifestations of Obsessive-Compulsive Disorder. Journal of the American Academy of Psychiatry and the Law, 42, 66-74. http://www.jaapl.org/content/42/1/66

Veale, D., Freeston, M., Krebs, G., et al (2009) Risk assessment and management in obsessive-compulsive disorder. Advances in Psychiatric Treatment, 15, 332-343. http://doi.org/10.1192/apt.bp.107.004705

Finkenbine, R. (2000) Comment on 'Assaultive Eye Injury and Enucleation'. Journal of the American Academy of Psychiatry and the Law, 28, 250-251. http://www.jaapl.org/content/28/2/250.2.short

Edwards, H. & Higham, L. (2020) ASD, OCD and violence - a forensic case study. Journal of Intellectual Disabilities and Offending Behaviour, 11, 1-8. https://doi.org/10.1108/JIDOB-07-2019-0015

Arnold, L. M. (1999) A Case Series of Women With Postpartum-Onset Obsessive-Compulsive Disorder. Primary Care Companion to the Journal of Clinical Psychiatry, 1, 103-108. https://doi.org/10.4088/pcc.v01n0402

Hatters Friedman, S. & Resnick, P. J. (2007) Child murder by mothers: patterns and prevention. World Psychiatry, 6, 137-141. https://www.ncbi.nlm.nih.gov/pubmed/18188430