When we were planning this issue, several friends and readers were a bit surprised. "A whole issue on OCD? Is there anything new to say about it?"

There's plenty to say that's both new and old. The purpose of this issue is to remind you of some "old" things you may have forgotten, and to provide you with a "State of the Union" address for one of the more fascinating syndromes in psychiatry.

As clinicians, we risk becoming a little blasé about diagnosing OCD. We're quite good at asking the right diagnostic questions (like, "Do you find that you have silly thoughts or worries that pop into your head a lot, that cause you to check things or wash yourself excessively?"). But sometimes we don't appreciate what a complex cognitive process obsessions actually are.

Many patients describe obsessions as having two stages. Stage 1 is the intrusive thought that pops into the mind uninvited. "Did I lock the door? Did I wash well enough?" Normal people and well-treated patients are able to answer Stage 1 questions appropriately with "Yes I did," and move on with life. Patients with active OCD progress to Stage 2, in which they latch onto the worry and ponder it, well, obsessively. This leads to mounting anxiety, which can only be resolved by a behavior designed to quell the worry. Teaching patients this two-stage process of obsessions can be the key to helping them get some control over them.

DSM-IV field trials of hundreds of OCD patients revealed some findings that you'll probably find useful in your practice. For example, the vast majority (91%) of these patients reported both obsessions and compulsions, whereas practicing clinicians tend to believe that many of their patients are more or less "pure" obsessives or "pure" compulsives. If you find yourself diagnosing large numbers of OCD patients as predominantly obsessive or compulsive, chances are good you're not digging deeply enough during the interview.

Quick Facts on OCD

• Prevalence: About 2% worldwide


• Age of Onset: 20 years


• Female to Male Ratio: 1.5: 1.0


• Heritability: Unclear; evidence mixed so far


• Comorbidity: Depression, 30%; Panic Disorder and Social Phobia, 15-25%; Tics, 10-20%; Personality Disorders common (mainly Avoidant, Dependent, and Obsessive Compulsive)

It sometimes seems that there are infinite variations on a theme when it comes to OCD, which can make categorizing a given patient's symptoms overwhelming. Factor analytic studies have found that four categories of symptoms account for most the variation:

1. fears of potential harm, leading to checking behavior;


2. need for symmetry, leading to ordering;


3. contamination fears and subsequent washing; and


4. difficulty discarding things with hoarding (Am J Psychiatry 1997; 154:911-917).

What about PANDAS? Not the endangered bears, but "Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococci." This putative syndrome consisting of abruptly-appearing OCD symptoms, tics, and neurological problems in association with a recent strep infection is thought to be caused by anti-strep antibodies attacking the basal ganglia. Fascinating stuff, but does PANDAS really exist? It was first described in a case series of 50 children in 1998 (Am J Psychiatry 1998;155:264-271), and controversy has raged ever since.

This is hardly an academic exercise. As psychiatrists, we diagnose plenty of pre-pubertal kids with OCD and tics. Should we be referring all of them to their pediatricians for a throat culture and a trial of penicillin? Currently, the answer appears to be "no." As argued in a recent review in a pediatric journal (Pediatrics 2004; 113:883-6), PANDAS remains an unproven hypothesis. One reason is that strep infections are incredibly common in kids, so that finding strep antibodies in a child with OCD may well be coincidental. On a more practical level, the only trial of prophylactic penicillin in such children showed no benefit, and a more recent positive report of antibiotic treatment was not placebo-controlled. However, if your little OCD patient has a bad sore throat, you'd do well to send them to be swabbed, just in case.

Roll up your sleeves when dealing with your OCD patients, because they frequently suffer comorbid major depression, panic disorder, and social anxiety disorder. And don’t forget to dig for personality disorders, especially avoidant PD, dependent PD, and of course, obsessive compulsive PD, all of which are common in OCD.

Regarding treatment, the bottom line is that all the SSRIs work equally well for OCD. Most psychiatrists would agree that you have to push SSRI doses up to 2 or 3 times the unit dose for best effect. While this may be true, you should probably know that this is based on hard data from only two agents--Prozac (fluoxetine) and Paxil (paroxetine)--in which fixed dose studies have documented the superiority of 60 mg over 20 mg doses (for citations, see Zohar and Fineberg, Practical Pharmacotherapy, in Obsessive Compulsive Disorder: A Practical Guide, 2001, Martin Dunitz). A study of Zoloft reported the odd result that both 50 mg and 200 mg doses were effective in OCD but that 100 mg was not (Arch Gen Psych 1995; 52:289-295).

Of course, there's a lot more to OCD treatment than this. See this month's interview with Dr. Lorrin Koran for a beautiful outline of practical psychopharmacology tips for OCD, including augmentation strategies. Another article in this issue reviews psychotherapy strategies that you can fold into your psychopharmacology practice.

TCR VERDICT
OCD: Common, fascinating, and treatable.