Major Depressive Disorder - Psychiatry

Snapshot
A 51-year-old female presents to her PCP with a sore throat. Upon further screening, the patient shares concerns of difficulty with sleep, concerns about making mistakes in her life, and observations of decreased ability to focus at work as an administrative assistant for the past three months. She occasionally feels anxious about repeating past mistakes, which she cannot articulate. She goes on to express guilt about the death of some of her family members. She reports having experienced bouts of intense energy and uncontrollable thinking during which she felt very productive at work without need for sleep just prior to her current state. She denies any suicidal or homicidal thoughts. She denies any family history of depression or bipolar disorder. She denies worsened symptoms with menses. Physical exam is unremarkable, but the patient remarks a low appetite that has led to 3 pounds of weight loss. The PCP diagnoses the woman with major depressive disorder with mixed features and with anxious distress. The patient is started on escitalopram and scheduled for a follow-up appointment in two weeks.
Introduction
Mood state, syndrome, and/or mental disorder characterized by dysphoria (sad/irritable) Most common psychiatric disorder Epidemiology 18% prevalence in the United States females affected twice as often as males not associated with economic status or race incidence decreases with increasing age however, associated with presence of multiple medical comorbidities Classifications (DSM-V) unipolar major depression (major depressive disorder) persistent depressive disorder (previously called dysthymia) no scientifically meaningful distinction between chronic depression and dysthymia symptom persistence for > 2 years disruptive mood dysregulation disorder new diagnosis for children up to 18 years with persistent irritability and behavior dyscontrol created due to concerns of overdiagnosis of bipolar disorder premenstrual dysphoric disorder substance/medication induced depressive disorder depressive disorder due to another medical condition unspecified depressive disorder
Presentation
Symptoms SIG E CAPS Sleep decreased Interest decreased (anhedonia) Guilt increased Energy decreased Concentration decreased Appetite decreased Psychomotor retardation Suicidal ideations

Evaluation

Routine outpatient screening now recommended by USPSTF
- Patient Health Questionnaire-2 (PHQ-2) can be used
  - if positive, follow up with PHQ-9
  - assess for suicidal ideation, plan, and intent

Diagnostic criteria
- core symptom criteria have not changed in DSM-V
- one or more major depressive episodes
  - a depressive episode must contain five or more of the above symptoms
- for episodes > 2 week period separated by 2 month period
- impairment of daily living
- medical causes has been ruled out (e.g., hypothyroidism, adrenal insufficiency, Huntington's disease, hypercortisolism, mononucleosis, Parkinson's disease, stroke, lupus, TBI, vitamin B12 deficiency)
Subtype specifiers
- anxious distress
- atypical features
  - appetite increased
  - reactive to pleasurable stimuli
  - hypersomnia
  - heavy feelings in limbs
  - longstanding pattern of hypersensitivity to rejection
- catatonia
  - symptoms improve with benzodiazepines (i.e., lorazepam)
- mixed features
  - at least three symptom criteria for mania/hypomania

Treatment

Routine outpatient screening now recommended by USPSTF Patient Health Questionnaire-2 (PHQ-2) can be used if positive, follow up with PHQ-9 1st line: psychotherapy + pharmacotherapy psychotherapy cognitive-behavioral therapy or interpersonal psychotherapy pharmacotherapy selective serotonin reuptake inhibitors (SSRI) first line drug fewer side effects overall need > 4 weeks to take effect sudden cessation of therapy can lead to SSRI discontinuation syndrome SNRI, atypical agents (bupropion, mirtazapine) second line drugs first line if also treating neuropathy bupropion preferred for smoking cessation, is weight neutral, and does not have sexual side-effects TCAs and MAO inhibitors third line particularly effective when atypical symptoms present Electroconvulsive therapy for refractory cases, depression with psychotic features, or if immediate symptom resolution is required
Prognosis
Prognosis medical therapy effective in up to 70% of patients though must allow sufficient time for success and treat for minimum of 6 months results observable typically in 2 weeks follow-up usually at 2 weeks because risk of suicide is greatest following initial use of antidepressants if patient has had 1 episode of major depression, pharmacotherapy can be discontinued after 6 months of no symptoms can be monitored using PHQ-9 (not PHQ-2) complications pseudodementia dementia secondary to depression rule out organic causes before making this diagnosis (such as a TSH level)