This document discusses obsessive compulsive disorder (OCD). It provides a brief history of OCD and how it was previously understood. It then discusses prevalence, characteristics, DSM-5 classification, symptoms including obsessions and compulsions. The neurobiology of OCD is explored including genetics, neuroanatomy, the role of serotonin and dopamine, and neural correlates of OCD symptom factors. Associated symptoms, spectrum disorders, comorbidities, differential diagnosis, and treatment are also summarized.

2. Obsessive Compulsive
Disorder Biology and
Management
Prof. Hani Hamed Dessoki, M.D.PsychiatryProf. Hani Hamed Dessoki, M.D.Psychiatry
Prof. PsychiatryProf. Psychiatry
Chairman of Psychiatry DepartmentChairman of Psychiatry Department
Beni Suef UniversityBeni Suef University
Supervisor of Psychiatry DepartmentSupervisor of Psychiatry Department
El-Fayoum UniversityEl-Fayoum University
APA memberAPA member

4. History
• Since the fourth century BC, obsessional behaviour
was explained as “melancholia”, a distinct disease
with particular mental and physical symptoms.
• Melancholia (Greek for black bile) was supposedly
caused by an imbalance the four bodily fluids or
humours.
• Hippocrates, in his Aphorisms, characterized “all
fears and despondencies, if they last a long time" as
being symptomatic of melancholia.

5. History
• In 17th century England, the concept of
"religious melancholy" became established as
the cause of a many mental disorders
including those with OCD-like symptoms.

6. Facts and Figures
• Prevalence
– Originally believed to be rare
• >0.1%
– Recent evidence suggests 1-3% Onset
/ Characteristics:
– Males:, high prevalence of checking
– Females:, high prevalence of washing

7. OCD in DSM 5
APA 2013
CHANGE
Removes obsessive-compulsive disorder from
category of Anxiety Disorders and places it in
new category of Obsessive-Compulsive and
Related Disorders
Obsessive-Compulsive Disorder
Body dysmorphic disorder
Hoarding disorder
Hair-pulling disorder (trichotillomania)
Excoriation (Skin-Picking) disorder
Substance/Medication –induced OCD
Others
Obsessive-Compulsive and related
Disorders

8. OCD
 undesired, Irrational, Intrusive, Repetitive
compulsions or obsessions, (Ego- Dystonic,
alien), unwanted thought, urges or actions,
unsuccessful ability to resist, unacceptable
(Patient realizes its absurdity) + anxiety and
impaired functioning

9. What is an Obsession?
• Involuntary intrusive cognition
• Types
• Doubts (74%)
• Thinking (34%)
• Fears (26%)
• Impulses (17%)
• Images (7%)
• Other (2%)

10. Themes in Obsessions
• Obsessions often have common themes
– Contamination, dirt, disease, illness (46%)
– Violence and aggression (29%)
– Moral and religious topics (11%)
– Symmetry and sequence (27%)
– Sex (10%)
– Other (22%)
• The themes often reflect contemporary
concerns (the devil, germs, AIDS)

11. Linking Obsessions and
Compulsions

12. OCD and “Normal” Experience
• Obsessional thoughts found in 90% of
people
– It is well replicated that 80%+ of normal people
have intrusive thoughts
– There thoughts are similar in content and form
to OCD patients
• Compulsions
– Many people have compulsions such as
stereotyped or superstitious behaviors
– 66% of normal people report some form of
checking behavior
• Is OCD qualitatively distinct?

13. NEUROBIOLOGY OF OCD
A.Genetics
1. Twin Studies - high concordance in
monozygotic twins.
2. Family Studies - frequency of OCD
higher among 1st degree relatives.
3. Link between TS and OCD
a. 50% of TS have OCB
b. Sex-specific phenotype (females who
inherit TS gene may only have OCB)

14. NEUROBIOLOGY OF OCD
B. Neuroanatomy
1. Basal ganglia dysfunction
a. OCB is observed in movement
disorders (PD, HD, TS)
b. High conc. 5-HT in BG
2. “Frontal Lobe” Dysfunction
a. Abnormalities on imaging
b. Hypermetabolism on PET
c. Similar patterns of cognitive test
performance

17.  (5HT) exaggerated sensitivity of post-synaptic 5HT1A &
2A , as well as abnormal reg. of pre-synaptic 5HT1A
 Stimulation of 5HT1B, 1C, 1D exacerbate OCD
 Stimulation of 5HT3 exacerbate anxiety, OCD?
The role of serotonin
Pytliak M et al. Physiol. Res. 2011, 60:15-25
Camarena B et al., International Journal of Neuropsychopharmacology (2004), 7, 49–53.

18. Family of 5HT receptors
Mood
Exacerbate OCD
Anxiety, agitation, appetite
Exacerbate OCD
Sleep-sex-anxiety
Anxiety, GIT
Anxiety, appetite, ↓ learning
Sleep
Anxiety, cognition
Anxiety, memory
Pytliak M et al. Physiol. Res. 2011, 60:15-25
Camarena B et al., International Journal of Neuropsychopharmacology (2004), 7, 49–53.

19. Treatment of moderate to severe
depression - SSRIs

20. 5HT in Vesicles5HT in VesiclesPre synapsePre synapse
5HT 1a
Anti.
DEP.
5HT2
Sleep
Sex
5HT 3
G.I.T.
Disturbances
Post Synaptic
Rs
Post Synaptic
Rs
Reuptake.

21. Proves of 5HT Dysfunction in OCD
1. Efficacy of SSRIs and clomipramine
2. Serotonin receptor dysfunction
3. Hypersensitivity of postsynaptic 5-HT receptors
4. Treatment response correlated with decreased CSF serotonin
metabolite 5-HIAA in OCD patients
5. Administration of m-chlorophenylpiperazine (mCPP), which
decreases seroternergic activity, increases obsessional symptoms
6. Correlations of platelet 5-HT transporter dysfunction, 5-HT
concentrations and monoamine oxidase activity with symptom
severity and response to SSRIs
7. Challenge tests suggest 5-HT1 receptors altered in OCD
8. Polymorphisms of 5-HT transporter linked to OCD

22.  OCD responds to dopamine antagonists
 Exacerbation with stimulants (increases DA activity) i.e.
Dextroamphetamine, methylphenidiate
 The dopamine metabolite HVA is low in CSF
 Related to early onset OCD
 Related to hoarding disorder
 Dopamine in PFC may have its role in control of
emotions?
Neurochemical Aspect
The role of dopamine

23. » 5HT1A is dopamine accelerator. However,
5HT2A is dopamine brake (opposite
effect is on glutamate).

24. Neurochemical Changes

25. Neural correlates of OCD Symptom factors
Aggression / Harm
Contamination
Symmetry / Order
Saving / Collection
Increased activity of striatum
Increased activity of Orbito frontal
cortex & Anterior Cingulate Gyrus.
Decreased activity of striatum
Decreased activity of Cingulate
gyrus.
Ranch et al 1998; Saxena et al 2003.

26. Associated Symptoms
• Amygdla  different structures in the
brain stem.
• Hypothalamus – Cortisol.
• Locus Ceruleus – Tachycardia.
• Parabrachial Nuclei – Tachypnea.
• Periaqueductal gray – Fight, Flight or Flee.

27. Neuroimmunological Aspect
 Paediatric Autoimmune Neuropsychiatric Disease Associated
with Streptococcal Infection – PANDAS

28. Neurocognitive Model
 Executive dysfunction in organizational strategies
 Set shifting problems
 Perseveration of responses
 Deficits in planning, problem solving
 Problems in decision making tasks
 Failure to predict and suppress the sensory
consequences of their actions
 Flexibility problem

29. Site Function
DLPFC Obsession
OFPFC Compulsion
VMPFC Affective

30. OCD
Neurologic
Tourettes
Sydenhams ch.
Torticolis
Autism
Preoccupation with bodily
sensation or appearance
Impulsive disorders
Sexual Compulsions
Trichotillomania
Pathological gambling
Kleptomania
Self injurious behaviors
BDD
Depersonalization
Anorexia Nervosa
Hypochondriasis
OCD Spectrum disorders

31. OCD Spectrum
OCD BDD A.N. DEP HYPO. T.S.
Trich
Binge Eating
Comp. Buy
Klep
PG
Sexual Comp.
BPD.
Anti Social PD
Compulsive Impulsive
Risk Aversive Risk Seeking

32. Psychiatric co-morbidities
Personality disorders
MDD
Simple phobia
Social phobia
Eating disorders
Bipolar disorder
Alcohol abuse
Comorbidities Estimated prevalence
63 %
28 to 31%
7 to 48%
11 to 16%
15%
8 to 13%
8%
Panic disorder 6 to 12 %

33. Differential Diagnosis
 Anxiety disorder Due to a
General Medical
Conditions
 Substance induced
Anxiety Disorder
 Body Dysmorphic
Disorder
 Obsessive compulsive
personality
 Pathological gambling
 Paraphillias
 Major Depressive
Episode
 Generalized Anxiety Dis.
 Hypochondriasis
 Specific Phobia
 Delusional Disorder
 Psychotic Disorder Not
Otherwise Specified
 Schizophrenia
 Tic/stereotypic behavior
Math SB and Janardhan RYC, Int J Clin Pract, July 2007, 61, 7, 1188-1197

34. ConclusionConclusion
• OCD is a disabling disorder which needs
integrative evidence-based approach