Depression and Anxiety – Lecture 4 Notes

Core Concepts: Mood, Affect & Depression

Mood vs. Affect
- Mood = sustained emotional climate; Affect = moment-to-moment emotional "weather"
- Helpful analogy: Mood is to affect as climate is to Melbournian weather
DSM-5-TR Mood-Disorder umbrella
- Primary disturbance = abnormal elevation or depression of mood
- Secondary disturbances may include psychosis, anxiety, etc.

### Unipolar vs. Bipolar Disorders

- Continuum of mood states

- \text{Mania} \; \rightarrow \; \text{Hypomania} \; \rightarrow \; \text{Euthymia ("normal")} \; \rightarrow \; \text{"Dysthymia"} \; \rightarrow \; \text{Major Depression}*

- Unipolar: oscillation occurs on one side (depressive pole)

- Bipolar: oscillation spans both poles (mania/hypomania & depression)

DSM-5-TR: Major Depressive Episode (MDE)

Diagnostic threshold: \ge 5 $symptoms for$ \ge 2\,\text{weeks} $, representing change from prior functioning</li><li>Symptom list (need at least one of first two)<ol><li>Depressed mood</li><li>Anhedonia (loss of interest/pleasure)</li><li>Appetite/weight change (loss or gain)</li><li>Sleep change (insomnia or hypersomnia)</li><li>Psychomotor agitation or retardation</li><li>Fatigue / low energy</li><li>Feelings of worthlessness or inappropriate guilt</li><li>Diminished concentration / indecisiveness</li><li>Recurrent thoughts of death or suicidality</li></ol></li><li>Specifiers add clinical nuance<ul><li>Psychotic features (mood-congruent vs. incongruent)</li><li>Melancholic, catatonic, postpartum onset, anxious distress, seasonal pattern (SAD)</li></ul></li></ul><h5 id="e44d8bcf-4fa7-4ba3-aa8b-d5be02afaf2f" data-toc-id="e44d8bcf-4fa7-4ba3-aa8b-d5be02afaf2f" collapsed="false" seolevelmigrated="true">DSM-5-TR: Major Depressive Disorder (MDD)</h5><ul><li>Criteria = presence of$ \ge 1 $MDE</li><li>Exclusions<ul><li>Episode not better explained by other dx</li><li>No history of mania/hypomania/mixed episode unless substance/medical-induced</li></ul></li></ul><h5 id="fc26d04f-d3fb-4d3d-9a3c-58e71a248b96" data-toc-id="fc26d04f-d3fb-4d3d-9a3c-58e71a248b96" collapsed="false" seolevelmigrated="true">Biopsychosocial Case Formulation (Example "S",$ 33 $-year-old male)</h5><ul><li>Predisposing factors (increase lifelong vulnerability)<ul><li>Family psychiatric hx, childhood divorce, invalidating parenting, depressogenic cognitions</li></ul></li><li>Precipitating factors (proximal triggers)<ul><li>DUI with license loss, job loss, relationship strain, substance escalation, exercise cessation</li></ul></li><li>Perpetuating factors (maintain disorder)<ul><li>Ongoing substance use, malnutrition, behavioural depression, social network reinforcing maladaptive habits</li></ul></li><li>Model illustrates integrative lens linking biology, psychology, and environment</li></ul><h5 id="24535085-368d-4847-9d3b-3ddf9acdfafd" data-toc-id="24535085-368d-4847-9d3b-3ddf9acdfafd" collapsed="false" seolevelmigrated="true">Epidemiology of Depression</h5><ul><li>Family history multiplies risk$ 1.5\text{–}3\times $</li><li>Up to$ \$20\%\text{–}25\% $of individuals with major medical comorbidity (CVA, diabetes, cancer) develop MDD</li><li>High co-occurrence with anxiety disorders</li><li>Age/Sex trends (AUS$ 2020\text{–}21 $): Affective-disorder prevalence peaks in females$ 16\text{–}44; male curve flatter

Anxiety & Anxiety-Related Disorders (DSM-5-TR categories)

Panic Disorder (PD)
Specific Phobia
Social Anxiety Disorder (SAD)
Generalised Anxiety Disorder (GAD)
OCD, PTSD, Acute Stress Disorder, Medical/Substance-induced, NOS

Epidemiology (AUS 2020\text{–}21)

Female > Male across all anxiety subtypes
Highest 12\text{-month} $prevalence in$ 16\text{–}24 $age band</li></ul><h5 id="e88c8630-af6f-4f42-be13-6c14417f1fbb" data-toc-id="e88c8630-af6f-4f42-be13-6c14417f1fbb" collapsed="false" seolevelmigrated="true">DSM-5-TR: Panic Disorder</h5><ul><li>A. Recurrent unexpected panic attacks—abrupt surge of intense fear/discomfort peaking within minutes<ul><li>Need$ \ge 4 $of$ 13 $listed somatic/cognitive symptoms (palpitations, sweating, choking, etc.)</li><li>Culture-specific symptoms not counted toward threshold</li></ul></li><li>B. At least$ 1 $attack followed for$ \ge 1\text{ month} $by<ul><li>Persistent worry about future attacks/consequences</li><li>OR maladaptive behaviour change (avoidance, exercise restriction, etc.)</li></ul></li><li>C. Not due to substance/medical condition</li><li>D. Not better explained by other mental disorder</li><li>Epidemiology add-ons<ul><li>$ 30\text{–}50\% $develop agoraphobia</li><li>$ 50\text{–}60\% $lifetime MDD (~(\sim\frac{1}{3}) current)</li><li>$ 20\text{–}25\% substance-dependence history

DSM-5-TR: Generalised Anxiety Disorder (GAD)

A. Excessive anxiety & worry more days than not for \ge 6\text{ months} $about multiple domains</li><li>B. Difficult to control worry</li><li>C.$ \ge 3 $/$ 6 $physiological-cognitive symptoms (children need$ 1 $)<ol><li>Restlessness/on edge</li><li>Easily fatigued</li><li>Difficulty concentrating / blank mind</li><li>Irritability</li><li>Muscle tension</li><li>Sleep disturbance</li></ol></li><li>Comorbidity<ul><li>$ 90\% $lifetime with another disorder;$ 66\% $current</li><li>Worse$ 5-year prognosis than PD

Understanding Comorbidity

Tripartite Model (Clark & Watson 1991):
- Shared Negative Affect dimension explains overlap of anxiety & depression
- Low Positive Affect (\rightarrow) depression-specific; Physiological Hyperarousal (\rightarrow) anxiety-specific
HiTOP (Hierarchical Taxonomy of Psychopathology)
- Organises symptoms (\rightarrow) components (\rightarrow) syndromes (\rightarrow) spectra (\rightarrow) super-spectra
- MDD & GAD cluster within Distress subfactor of Internalising spectrum
- Emphasises dimensional, transdiagnostic traits over categorical disorders
Clinical implication: Focus on core emotional dysregulation may streamline treatment (Unified Protocol)

Case Illustration: James

DSM-5-TR: Two comorbid disorders (MDD + GAD) (\rightarrow) treat separately
HiTOP: Single internalising profile (\rightarrow) one transdiagnostic intervention

Behavioural & Cognitive Models of Depression

Behavioural Model (Lewinsohn)
- Environmental scarcity of positive reinforcement (\downarrow) operant behaviour (\rightarrow) further loss of reinforcement (\rightarrow) Depression spiral
Beck’s Cognitive Model
- Early negative experiences craft dysfunctional schemas
- Critical incident triggers schema (\rightarrow) Negative Automatic Thoughts (NATs)
- Negative Cognitive Triad: self, world, future
ABC Model (Ellis)
- A = Activating Event (e.g., failing exam)
- B = Belief ("I will never succeed")
- C = Consequence (sadness, withdrawal)
- Interventions target B to change C

Integrated Clinical Takeaways

Diagnostic clarity: recognise full DSM criteria, specifiers & rule-outs
Epidemiological awareness guides screening in high-risk groups (young females, medical comorbidity)
Case formulation should blend predisposing, precipitating, perpetuating factors across bio-psycho-social axes
Categorical (DSM) vs. dimensional (HiTOP) lenses offer complementary insights
- DSM beneficial for reliability, insurance, research inclusion
- HiTOP elucidates shared etiology & informs transdiagnostic treatments (e.g., Unified Protocol)
Tripartite & cognitive-behavioural theories explain mechanisms (negative affect, reinforcement loss, maladaptive cognitions)
Understanding comorbidity crucial: common co-occurrence (e.g., \gt 50\% $PD+MDD,$ 90\%$$ GAD with another disorder) affects prognosis & treatment planning

### Learning Objectives—Self-Check

- Can you list DSM diagnostic features for MDD, PD, GAD?

- Explain difference between specifiers & subtypes?

- Contrast DSM vs. HiTOP conceptualisations?

- Describe Tripartite Model & treatment implications?

- Apply behavioural/cognitive frameworks to a case?

- Use epidemiological data to inform assessment?