4.2.2 Mood Disorders: DMDD, PDD & PMDD

Context & Framing

  • Unit focuses on mood-related disorders that are less frequently discussed in popular media than MDD or Bipolar I/II.
  • Lack of visibility ≠ rarity; prevalence can still be significant.

Disruptive Mood Dysregulation Disorder (DMDD)

  • Population: Children and adolescents.
  • Core Feature: Chronic, severe, developmentally inappropriate irritability and tantrums.

DSM-5 Criteria (A–K)

  • A. Temper outbursts
    • Severe, recurrent (verbal OR behavioral).
    • Out of proportion to provocation in intensity and/or duration.
  • B. Developmental mismatch
    • Response inconsistent with age-appropriate emotional control (e.g., 9-y-o behaving like a 3-y-o).
  • C. Frequency
    • \ge 3 outbursts per week (average).
  • D. Baseline mood
    • Persistently irritable/angry most of the day, nearly every day, observable by parents, teachers, peers.
  • E. Chronicity
    • Criteria A–D present \ge 12 months with no symptom-free interval > 3 consecutive months.
  • F. Cross-situational
    • Occurs in at least 2 of 3 settings: home, school, peers (must be severe in ≥1).
  • G. Age window for 1st diagnosis
    • Not before 6, not after 18.
  • H. Onset
    • Symptoms present before age 10.
  • I. No manic/hypomanic episodes
    • Never a period >1 day meeting full (except duration) criteria for mania/hypomania.
    • Normal, developmentally appropriate excitement ≠ mania.
  • J. Exclusions
    • Not exclusively during MDD; not better explained by Autism Spectrum Disorder (ASD), PTSD, Separation Anxiety, Persistent Depressive Disorder, etc.
    • Cannot coexist with Oppositional Defiant Disorder (ODD), Intermittent Explosive Disorder, or Bipolar Disorder.
    • May coexist with ADHD, MDD, Conduct Disorder, Substance Use Disorder.
    • If both DMDD & ODD criteria met ➔ diagnose DMDD only.
    • If any manic/hypomanic episode ➔ do NOT diagnose DMDD.
  • K. Substance/Medical rule-out
    • Not attributable to drugs, medication (e.g., corticosteroids), or neurological conditions.

Developmental Neuro-tie-in

  • Prefrontal cortex matures until ~25–30 → natural child impulsivity. DMDD reflects extreme deviation.

Practical / Ethical Points

  • Mislabeling normal pediatric mood swings as DMDD risks unnecessary medication.
  • Importance of multi-informant assessment (parents + teachers + peers).

Persistent Depressive Disorder (PDD; a.k.a. Dysthymia)

  • DSM-5 merged chronic MDD + dysthymic disorder into PDD.
  • Characterized by long-standing, low-grade depression.

DSM-5 Criteria

  • A. Duration of depressed (or irritable in youth) mood
    • Most of the day, more days than not.
    • Adults: \ge 2 years; Children/Adolescents: \ge 1 year.
  • B. Additional Symptoms (need ≥2)
    1. Poor appetite OR overeating.
    2. Insomnia OR hypersomnia.
    3. Low energy/fatigue.
    4. Low self-esteem.
    5. Poor concentration/indecisiveness.
    6. Feelings of hopelessness.
  • C. Symptom persistence
    • No break > 2 months during required period.
  • D. May have superimposed MDD episodes
    • “Double depression.”
  • **E. No mania/hypomania or cyclothymia.
  • F. Rule-outs: Schizoaffective, schizophrenia, delusional disorder, etc.
  • G. Substance/Medical exclusion (e.g., hypothyroidism, medications).
  • **H. Clinically significant distress/impairment.

Specifiers

  • With anxious distress, atypical features, partial/full remission, early (<21) vs. late onset (≥21).
  • Course: persistent major depressive episode, pure dysthymic syndrome, intermittent MDD (with/without current episode).
  • Severity: mild, moderate, severe.

Prevalence

  • 12-mo U.S. estimate:
    • Dysthymia \approx 0.5\%.
    • Chronic MDD \approx 1.5\%.
  • Female : male ratio ≈ 1.5–2:1.

Premenstrual Dysphoric Disorder (PMDD)

  • Affects individuals with menstrual cycles.
  • Timing: final week before menses → improves within days of onset → minimal 1 week post-menses.

DSM-5 Criteria

  • A. Cyclical symptom pattern: ≥5 symptoms in most cycles during previous year.
  • B. At least 1 (often several) affective symptoms
    1. Marked affective lability (mood swings, tearfulness, sensitivity to rejection).
    2. Marked irritability/anger; ↑ interpersonal conflict.
    3. Marked depressed mood, hopelessness, self-deprecation.
    4. Marked anxiety/tension, keyed-up/on-edge.
  • C. Additional symptoms (to reach total of 5 with B items)
    • Decreased interest in usual activities.
    • Difficulty concentrating.
    • Lethargy, easy fatigability, low energy.
    • Marked change in appetite; specific cravings or overeating.
    • Hypersomnia or insomnia.
    • Sense of being overwhelmed/out of control.
    • Physical symptoms: breast tenderness/swelling, joint/muscle pain, bloating, weight gain.
  • D. Clinically significant distress or impairment in work, school, social life, relationships, productivity.
  • E. Not merely an exacerbation of another disorder (though can co-occur).
  • **F. Prospective daily ratings for ≥2 symptomatic cycles recommended for confirmation (provisional dx before).
  • G. Substance/medical exclusion (e.g., hyperthyroidism, medications).

Illustrative Example

  • A college student tracks symptoms daily: notes 6 symptoms (irritability, mood swings, cravings, hypersomnia, breast tenderness, lethargy) appearing 5 days pre-menses, resolving 3 days after. Prospective charting over 3 cycles → meets PMDD.

Substance/Medication-Induced Depressive Disorder

  • Catch-all for depressive presentations directly caused by substances/meds or medical conditions.
  • Ensures patients like “4-y-o on steroids with ‘roid rage’ ” are coded accurately, avoiding mislabeling as DMDD/PDD/MDD.

Clinical / Ethical Notes

  • Reminds clinicians to screen for thyroid, steroid use, illicit drugs, chemotherapy agents, etc.
  • Treatment approach targets underlying cause (taper steroid, treat thyroid), not primary antidepressant by default.

Cross-Disorder Themes & Connections

  • Rule-Out Logic
    • Always exclude: substance effects, medical conditions, psychotic disorders, manic/hypomanic episodes when diagnosing unipolar disorders.
  • Developmental Considerations
    • Irritability in children may signal DMDD, PDD (irritable subtype), or normal dev’mt. Context crucial.
  • Gender & Hormonal Factors
    • Women’s higher prevalence in PDD and presence of PMDD highlight hormonal, social, and diagnostic biases.
  • Functional Impairment as a diagnostic linchpin across all disorders.

Real-World Relevance

  • School psychologists must differentiate DMDD from ODD for appropriate IEP interventions.
  • Primary-care physicians should monitor mood when prescribing long-term corticosteroids.
  • Workplace accommodations may be warranted for individuals with PDD (e.g., flexible scheduling, light therapy).
  • Awareness of PMDD supports destigmatizing conversations about menstrual mental health.

Key Numbers & Formulas Recap

  • DMDD frequency: \ge 3 outbursts/week.
  • DMDD chronicity: \ge 12 months, no >3-mo gap.
  • PDD duration: Adults \ge 2 yrs; Youth \ge 1 yr; symptom-free gap <2 mo.
  • PMDD symptom count: \ge 5 total, incl. \ge 1 affective (B).

Study Tips

  • Make a timeline chart contrasting duration criteria: DMDD (12 mo), PDD (24 mo), MDD (2 weeks), PMDD (cyclical).
  • Use mnemonic “T-FIT” for DMDD core: Tantrums (≥3/wk), Frequency (≥12 mo), Irritable baseline, Two settings.
  • For PDD, remember “HEALS” for symptom cluster: Hopeless, Energy low, Appetite change, sLeep change, Self-esteem low.
  • Track prospective symptom diaries for PMDD case vignettes.