Impact of Obsessive-Compulsive Personality Disorder (OCPD) on treatment of OCD

[David Baxter PhD]

The impact of obsessive-compulsive personality disorder on treatment outcomes in exposure and response prevention (EXRP)
by Michael D. Anestis, M.S., Psychotherapy Brown Bag
June 15, 2011

Just about any clinician can tell you that the presence of a personality disorder can derail even treatments with monumental amounts of empirical support. Today, I want to provide some evidence to support that notion through a quick recap of a study in press at Behaviour Research and Therapy, conducted by Anthony Pinto, Michael Liebowitz, Edna Foa, and Blair Simpson. In this study, the authors examined the degree to which the presence of obsessive compulsive personality disorder (OCPD) predicted treatment outcomes for individuals receiving exposure and response prevention (EXRP) for obsessive compulsive disorder (OCD).

Before explaining the study, let me clarify a few points:

1. EXRP is, by far, the treatment with the greatest level of empirical support in the treatment of OCD. Click here to read all articles we've written about this treatment.
2. OCPD and OCD, while similarly named and certainly related to one another, are distinct conditions. Yes, it's frustrating that their names are so similar, but what can you do?

We haven't spent a ton of time discussing OCPD, so I want to give a quick recap of the DSM-IV-TR criteria for the disorder. Like all PDs, it must be a long-standing pattern that leads to functional impairment and/or distress across multiple domains of life. Specifically, the disorder is primarily based upon a preoccupation with orderliness, perfectionism, and cognitive inflexibilty and a diagnosis requires endorsement of four or more of the following symptoms:

• Perfectionism/preoccupation with details, lists, order to the extent that the point of the activity is lost
• Excessive devotion to work at the expense of functional relationships and liesure
• Scrupulocity and inflexibility about morality and ethics
• Inability to discard worn-out or worthless items (hoarding)
• Refusal to delegate tasks to others
• Miserly
• Rigidity and stubborness

In this particular study, the authors used data from a randomized controlled trial in which adults with OCD currently prescribed a therapeutic dose of a seletive serotonin reuptake inhibitor (SSRI) were assigned to also receive either EXRP Or stress management training. That original study (Simpson et al., 2008) found that only EXRP was an effective augmentation for the SSRI, but that's not the focus here.

Of the 54 patients assigned to receive EXRP, 49 had been assessed for personality disorders using a structured diagnostic interview and these individuals were included in the analyses in this study. Additionally, because research has demonstrated that the hoarding symptoms of OCPD does not adhere well to the other symptoms (Nestadt et al., 2006) and will likely be dropped in the DSM-5 description of OCPD, the authors ran their analyses both with and without this symptom included (this did not impact results either way).

The authors found that, at baseline, individuals with and without OCPD did not differ on OCD severity as measured by the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) and OCPD symptoms were not significant correlated with Y-BOCS scores. In other words, any difference in treatment outcomes associated with OCPD could not simply be accounted for by the fact that those folks had more severe OCD symptoms.
Post-treatment, the authors found that both OCPD diagnosis (yes/no does the patient meet criteria for OCPD?) and OCPD symptoms (how many symptoms of OCPD does the patient endorse?) predicted worse EXRP outcomes. Importantly, the authors also examined whether all OCPD symptoms had a similar impact on treatment outcome. As it turns out, only one - perfectionism - predicted poorer response to treatment.

Perfectionism is not a bad thing in and of itself, but when it reaches extreme levels, it becomes highly predictive of a number of highly problematic outcomes. This study is simply one more example of that well-established point.

So, ultimately what was the point the authors were trying to make here? Even when applying the gold standard treatment for OCD, clinicians need to be careful to assess for OCPD, and particularly for perfectionism, as this can predict a poorer treatment response. Although future studies would need to be conducted indicating that treatment of perfectionism results in better EXRP outcomes, this study offers an initial level of support for that notion.

Articles referenced in text:

• Nestadt, G., Hsu, F.C., Samuels, J., Bienvenu, O.J., Reti, I., Costa, P.T. Jr., et al. (2006). Latent structure of the diagnostic and statistical manual of mental disorders, fourth edition personality disorder criteria. Comprehensive Psychiatry, 47, 54-62
• Pinto, A., Liebowitz, M.R., Foa, E.B., & Simpson, H.B. (in press). Obsessive compulsive personality disorder as a predictor of exposure and ritual prevention outome for obsessive compulsive disorder. Behaviour Research and Therapy.
• Simpson, H.B., Foa, E.B., Liebowitz, M.R., Ledley, D.R., Huppert, J.D., Cahil, S., et al., (2008). A randomized, controlled trial of cognitive-behavioral therapy for augmenting pharmacotherapy in obsessive-compulsive disorder. American Journal of Psychiatry, 165, 621-630.