Chapter 15: Obsessive-Compulsive and Related Disorders

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Okay, let's unpack this.

We are jumping into a deep dive on a really crucial area of modern psychiatry, obsessive, compulsive, and related disorders,

OCRDs.

That's right.

And our guide today is Chapter 15 of Kaplan and Sadok's Comprehensive Textbook of Psychiatry.

Yeah, exactly.

And our mission really is to give you a clear, structured understanding of this specific group of conditions.

And the big picture takeaway, sort of right out of the gate, is that creating this OCRD chapter in the newer diagnostic manuals, like DSM -5TR, that signals a pretty major shift.

Okay, so what's the significance of that shift?

Why group them together?

Well, it means we're finally properly acknowledging that these conditions share some fundamental common ground.

How they look immune.

Yeah, in how they look in a patient, how they present, but also, importantly,

how their brain circuitry seems to work.

There are overlaps.

And the ultimate goal here is to improve the recognition and the management of disorders that are actually incredibly common, but have historically been, well, underdiagnosed and definitely undertreated.

So we're talking about a family of disorders.

And for the DSM -5TR, who's in this family?

So the core group, the five main ones we'll cover,

are obsessive -compulsive disorder itself,

body dysmorphic disorder, hoarding disorder, trichotillomania, that's the hair -pulling one,

and excoriation disorder, which is skin picking.

Got it.

Okay, let's start with the one that kind of started it all research -wise.

OCD.

Can you just give us the quick definitions, those two core components?

Absolutely.

So think of it like a loop, often a relentless one.

Obsessions are where it starts.

These are those intrusive, unwanted, recurrent thoughts, or sometimes urges, or even images that just pop into your head.

Uninvited.

Totally uninvited.

And they cause immediate marked anxiety or distress, big time.

Okay, and the compulsions?

Compulsions are the behaviors that follow.

They're the repetitive physical acts, like, you know, checking the door 50 times.

Or they can be mental acts, too, like silently counting, praying, repeating words.

Things you do to try and make the anxiety go away.

Exactly.

The person feels driven, compelled to perform them.

And here's the key bit, right?

The compulsion is an attempt to neutralize the obsession or the anxiety it causes.

But it's either not connected in a realistic way, or it's just clearly excessive.

That's perfectly put.

The connection is illogical or way over the top.

Like the brain safety brick is just broken.

That's a great way to think about it.

And you know, it's also fascinating how our understanding of OCD has shifted academically.

How so?

Well, once upon a time, maybe early 20th century, it was really tied up in psychodynamic ideas, Freud and so on.

Right.

But now, it's really seen as a clear example of a neuropsychiatric disorder.

We understand it as being driven by specific malfunctions in brain circuits.

Which we'll get into.

And crucially, this isn't some rare, obscure condition.

Can you talk a bit about the real world impact?

Yeah, definitely not rare.

Data from the big NCSR study shows a lifetime prevalence of about 2 .3%.

Which is still significant.

It is.

And that's just meeting full criteria.

Subclinical OCD is way more common.

But the key thing the sources emphasize is how disabling it is.

It's associated with major comorbidity, very high rates of mood disorders, anxiety disorders, suicidal thoughts even.

And it often ranks globally among the most debilitating medical conditions.

It really impacts quality of life.

That's serious.

And it often starts quite early, doesn't it?

Yes.

The median age of onset is around 19.

But there's a key difference.

Early onset.

So we're talking by age 10, that's much more common in males.

Interesting.

And those individuals, the early onset males, are also more likely to have comorbid ticks.

Oh, okay.

So that foreshadows some connections we might talk about later.

Exactly.

It points towards some shared neurobiology.

Okay.

So moving to the official diagnosis, this is where it gets really interesting with the criteria.

To meet DSM -5 -TR criteria, the symptoms have to be time consuming.

What does that actually mean in practice?

It's a practical threshold.

It means the obsessions or compulsions have to take up a significant chunk of your day.

The guideline is typically more than one hour per day.

Wow.

Or, alternatively, they have to cause clinically significant distress or impairment, you know, messing up work, school relationships.

It has to be dominating your life in some way.

It can't just be an occasional quirky habit.

No, definitely not.

It's impairing.

And there's this critical specifier about insight.

How much the person recognizes their beliefs are.

Well, odd.

How does that affect things?

Right.

The insight specifier is crucial.

It runs on a spectrum from good or fair insight, where the person recognizes their OCD beliefs are probably not true, all the way down to absent insight or delusional beliefs.

Delusional.

Yeah.

About 4 % of people with OCD fall into that absent insight category.

They're completely convinced their obsessive beliefs are true.

So wouldn't that be diagnosis psychosis then?

Ah, this is the vital point.

The DSM says no.

Even with absent insight, if the core symptoms fit OCD,

you diagnose OCD, not a primary psychotic disorder like schizophrenia.

Why is that distinction so important?

Because it guides treatment.

It prevents the inappropriate use of anti -psychotic medications as a first line approach when What they likely need is OCD -specific treatment, like SSRIs or ERP.

That makes a huge difference to the patient getting the right treatment path from the start.

Absolutely.

It can save months, even years, of ineffective care.

Okay, before we leave the OCD diagnosis, let's circle back to those early onset cases you mentioned, the ones often linked with PICS.

The DSM have a Tourette -related specifier.

What does that tell us?

It basically signals a close familial and potentially neurobiological relationship.

Even though Tourette syndrome is classified separately, the fact that we specifically look for a history of tetics when diagnosing OCD reinforces this idea.

Suggests shared genetics or overlapping brain pathways.

Precisely.

Shared vulnerability in the brain's control systems, you could say.

Okay, so let's pivot from diagnosis to the mechanics.

If OCD is characterized by this rigid, repetitive behavior, what's going wrong in the wiring?

What's the underlying issue?

So the core idea, the main hypothesis, is that OCD represents a deficit in something called cognitive control.

Cognitive control.

Yeah, basically the brain gets stuck.

It shifts away from flexible, what we call goal -directed behavior, where you consciously decide, I want to do X to achieve Y, and shifts towards rigid, automatic, habit -driven behavior.

They get caught in these behavioral loops that can't easily stop.

And is there specific circuitry involved?

Can you give us the quick version of the corticothreadothalamic cortical loop?

The CSTC circuitry.

Yeah.

The CSTC loops, think of them as the brain's major decision -making, filtering, and action selection circuits.

They connect the thinking parts of the brain, the frontal cortex, down to the deeper action and habit centers, like the striatum, and then loop back up via the thalamus.

In OCD, brain imaging studies consistently show hyperactivity in certain parts of these loops, particularly areas like the anterior cingulate cortex, the orbitofrontal cortex, and parts of the striatum.

So it's like the brain's worry alarm or error signal gets stuck on.

That's a really good analogy.

It's like it's constantly firing, sending distress signals back through the loop, driving those compulsions.

Fascinating.

And presumably the treatments try to target this neurobiology, starting with the chemical side.

Exactly.

I mean, the initial serotonin hypothesis came about because the first effective drug was clomopriming, which is a potent serotonin reuptake inhibitor, an SRI.

And today, SSRIs, the selective serotonin reuptake inhibitors, are still the first -line medications.

But they're caveats for clinicians, right?

It's not quite like treating depression with SSRI.

Correct.

Two really important things to remember.

First, you often need higher doses for OCD than you typically use for depression.

Higher doses.

Got it.

And second, you need patience.

You need a longer duration of treatment, often at least 12 weeks at a good dose, before you can really judge if the medication is working or not.

Don't give up too early.

Twelve weeks.

But medication isn't the only starting point.

The chapter that stresses the foundation is psychoeducation.

Why is just talking about the diagnosis so critical?

It's absolutely foundational.

Because there's often so much shame and embarrassment associated with OCD symptoms.

People feel like they're going crazy.

Exactly.

The thoughts can feel alien, bizarre, even morally repugnant to the person experiencing them.

So providing clear, factual information.

Look, this is common.

It's treatable.

It's based in brain circuitry.

It's not a character flaw that's crucial.

Builds trust.

It builds trust.

It reduces self -blame.

And it really sets the stage for them to engage in what can be quite difficult therapy.

It fosters collaboration.

Speaking of difficult therapy, the main evidence -based psychological treatment is exposure and response prevention,

or ERP.

What does that actually involve for the patient?

It sounds tough.

It is challenging, no doubt, but it's incredibly powerful when done right.

So the E is for exposure.

The patient is systematically, gradually exposed in real life, or sometimes, imaginably, to their feared situation or trigger.

Then comes the RP, response prevention.

They actively, deliberately refrain from carrying out the usual compulsive ritual.

So if you fear contamination from door handles...

You touch the door handle, that's the exposure, and then you'd resist washing your hands for an agreed -upon period.

That's the response prevention.

And the idea is the anxiety eventually comes down on its own.

Exactly.

You learn through direct experience that the feared consequence doesn't happen, or that you can tolerate the anxiety without the ritual, and the anxiety naturally fades.

It breaks that fear -compulsion link.

Powerful stuff.

And for those cases that just don't respond well, even to combined medication and ERP, there are other options now, right?

More invasive ones.

Yes.

For highly treatment refractory cases, where people have failed multiple adequate trials, we now have options that directly target that CSTC circuitry.

Things like deep brain stimulation, or DBS.

Where they implant electrodes?

Precisely.

Targeting key nodes in the circuit, often the ventral striatum or ventral capsule area.

And there's also transcranial magnetic stimulation, TMS, which is non -invasive and uses magnetic pulses.

It's FDA approved for resistant OCD, typically used alongside behavioral therapy.

Okay, so that's a deep dive into OCD itself, the sort of engine of this OCRD category.

Now what about the other members of the family?

How does body dysmorphic disorder, BDD,

fit in?

Right, so BDD shares that core feature of preoccupation and repetitive behaviors.

But here, the preoccupation is with one or more perceived flaws in physical appearance.

Perceived flaws, meaning they aren't really there.

Or they're very slight, not really noticeable to other people.

But to the person with BDD, they seem huge, grotesque even.

And the repetitive behaviors.

Very similar structure to OCD compulsions.

Things like constant mirror checking, excessive grooming, skin picking related to the perceived flaw, reassurance seeking, comparing their appearance to others,

camouflaging.

And the impact.

Is it as severe as OCD?

Oh, absolutely.

The morbidity here is startlingly high.

Our sources point out that BDD has lifetime rates of suicidal ideation reaching, well, a terrifying 80%.

80 % what?

Yeah.

It causes immense suffering and impairment.

And a key diagnostic note here is the specifier for muscle dysmorphia.

What's that?

That's a specific form, more common in males, where the preoccupation isn't with a flaw, but with their body build being too small or not muscular enough.

They think they look puny when they might actually be quite muscular.

Right.

Okay.

And treatment.

Similar to OCD.

Broadly, yes.

SSRIs are again, first line pharmacotherapy.

CBT is the key psychotherapy, but it's often modified for BDD.

How so?

Well, it needs to address the typically very high levels of social avoidance and shame seen in BDD and sometimes incorporates things like perceptual retraining to help them challenge their distorted visual processing of the flaw.

Okay.

Let's move on to hoarding disorder, HD.

That was a relatively new addition as a distinct disorder, right?

What makes it different from just, you know, being a collector or having hoarding as part of OCD?

That's the crucial distinction.

Hoarding disorder involves persistent difficulty discarding possessions, regardless of their actual value.

This leads to clutter that basically compromises the intended use of their living spaces.

You can't use the kitchen, the bedroom.

Right.

But the why is different from OCD hoarding.

Exactly.

In hoarding disorder, the difficulty discarding stems from a perceived need to save the items, an intense distress associated with getting rid of them.

They might feel the item is useful, beautiful, or has sentimental value, even if it's objectively junk.

Whereas in OCD, hoarding might be driven by a fear.

Precisely.

Like someone hoarding newspapers because they fear they might accidentally throw away some crucial piece of information, the reason for the hoarding behavior is different.

Got it.

And does hoarding disorder follow the same pattern as OCD in terms of onset?

Actually no.

This is quite unique.

Unlike most other OCRDs, which tend to start earlier in life, the prevalence and severity of hoarding disorder seem to increase with age.

Interesting.

And treatment.

Is it the same approach?

It's trickier.

Specific CBT protocols have been developed for hoarding, focusing on skills like organizing, decision making about possessions, and resisting acquiring new things.

These are more effective than just waiting.

What about meds?

SSRIs?

They're used, but the evidence isn't as strong as for OCD or BDD.

In fact, the presence of hoarding symptoms often predicts a less favorable response to standard OCD treatments.

And because insight is often quite limited, people don't see the hoarding as a problem.

Techniques like motivational interviewing are really crucial to even get them engaged in treatment.

Right.

You have to build that motivation first.

Okay.

That brings us to the last pair.

The body focused repetitive behaviors,

or BFRBDs, trachotillomania and excoriation disorder.

Let's start with trachotillomania, TTM hair pulling.

Right.

TTM is characterized by recurrent pulling out of one's own hair, leading to hair loss.

Most commonly from the scalp, eyebrows, or eyelashes, but it can be anywhere.

And you mentioned earlier it's much more common in women.

Yes.

Highly skewed.

About a 9 .1 female to male ratio reported in clinical settings.

And interestingly, there seem to be two main styles of pulling.

Yeah, what they call focused pulling, where the person is quite aware of the urge building up and pulls intentionally, maybe to relieve tension.

And automatic pulling, which happens almost unconsciously, often when they're bored reading or watching TV.

Less awareness.

Okay.

And the other BFRBD, excoriation disorder, SPD,

skin picking.

Very similar structure.

SPD involves recurrent picking at one's own skin, leading to skin lesions and tissue damage.

Does it usually start randomly?

Often it begins somewhat innocuously.

Maybe after a minor skin condition like acne, a scab, or a bite.

But then the picking behavior takes on a life of its own and persists long after the initial trigger is gone, becoming the prime inner problem.

Right.

Now for treatment, you hinted earlier that these BFRBDs are a bit different from OCD and BDD.

SSRIs aren't the go -to.

They're often tried, but the results are much less consistent.

Standard SSRIs just don't seem to be as reliably effective for TTM and SPD compared to OCD or BDD.

So what does work pharmacologically?

You mentioned something cutting edge.

Well, what's gained significant traction, based on clinical trials, is the nutraceutical N -acetylcysteine, or NAC.

NAC.

What's that?

It's an amino acid derivative, available over the counter, actually.

It seems to act on the brain's glutamate system rather than serotonin.

Ah, so a different neurotransmitter pathway.

Exactly.

And trials, particularly in adults, have shown promising results for both TTM and SPD.

It highlights that these disorders might involve different neurochemical imbalances compared to classic OCD.

Very interesting.

And what about the psychotherapy?

Is it ERP?

No.

The gold standard psychotherapy for these BFRBDs is different.

It's called habit reversal therapy, or HRT.

Habit reversal.

How does that work?

HRT is quite structured and focuses on two core components.

First is awareness training.

Helping the person become much more aware of exactly when, where, and why the urges to pull or pick arise,

identifying the triggers and precursors.

Okay, becoming aware.

Then what?

Then comes competing response training.

This involves teaching the person to engage in a behavior that is physically incompatible with the pulling or picking whenever they feel the urge or notice they've started.

Like what?

Like making a tight fist, sitting on their hands, playing with a fidget toy, something that occupies the hands and makes the unwanted behavior impossible for a short period until the urge subsides.

So replace the habit with a harmless one.

Essentially, yes.

You practice this competing response repeatedly.

Okay, that makes sense.

Before we wrap this all up, the chapter also talks about differentiating these OCRDs from other things they might look like.

This is important for diagnosis, right?

How do we tell OCRD apart from, say,

just general worrying, like in generalized anxiety disorder?

That's a common question.

A good rule of thumb is to look at the content of the worry.

In GED, the worries are typically about real -life concerns, finances, job security, health, relationships.

They might be excessive, but they're grounded in reality.

OCRD obsessions, on the other hand, tend to be more bizarre, irrational, intrusive, and often feel very alien or against the person's values, what we call ego -dystonic.

The content feels different.

Got it.

And what about distinguishing OCRD compulsions from behaviors in impulse control disorders like pathological gambling or kleptomania?

They're also repetitive.

Key difference there is the motivation and the feeling associated with the behavior.

In impulse control disorders, the repetitive behavior is typically experienced as pleasurable, gratifying, or tension -releasing in the moment.

There's often an urge for pleasure.

Right.

OCRD compulsions are almost never described as pleasurable.

They're performed purely to reduce anxiety, distress, or prevent some dreaded outcome caused by the obsession.

They feel like a chore, a burden, not fun.

That's a clear distinction.

And briefly, the source material also mentions OCRDs that can be caused by medical conditions or substances.

Yes, it's important to be aware of those categories.

OCRD due to another medical condition, things like brain injuries affecting the striatum, or perhaps PANDAS, the pediatric autoimmune disorder linked to strep infections.

Right.

And also substance medication -induced OCRD.

For example, repetitive skin picking is sometimes seen with stimulant use, like cocaine.

These are theoretically interesting because they offer clues about the neurochemistry involved,

like dopamine's role, perhaps.

Okay, wow.

We have covered a huge amount of ground today.

Really run the gamut from the details of CSTC neurocircuitry and OCD, all the way to specific behavioral techniques for hair pulling.

We have.

And I think the big message from creating this OCRD chapter, as you said at the start, is that these conditions, which are really prevalent and can be incredibly impairing, are definitely related.

Absolutely.

They share underlying pathways, common features, and often respond, at least partially, to similar treatments like SRIs.

That's the spectrum idea.

But, and this seems like the crucial point for you, the learner, listening to this, the deep dive, really shows that understanding the shared biology, that common CSTC involvement, have to go hand in hand with respecting the critical differences.

Exactly.

Because the optimal treatment approach still varies quite dramatically.

You might need ERP for one person, HRT for another,

maybe NAC or specialized CBT for hoarding.

It's not one size fits all.

So the final provocative thought might be,

how do we best balance that?

How do we leverage the understanding of the shared neurobiology while still delivering that nuanced personalized care that respects the unique features of each disorder?

That's the ongoing challenge, isn't it?

Balancing the common threads with the individual clinical picture, a really compelling tension in the field.

Absolutely is.

Well, thank you so much for guiding us through that complex chapter.

It's been incredibly informative.

My pleasure.

And thank you for listening from the Last Minute Lecture Team.