Major Depressive Disorder
major depressive disorder (MDD)
- Major depressive disorder (MDD) has the highest prevalence of any psychiatric illness: ~ 7% of adults in the US have had a depressive episode.
- According to the DSM-5, the diagnosis requires at least 2 weeks of at least 5 of "D'SIG E CAPS" symptoms generally being present most of the day, nearly every day (if applicable).
- Make note that 1 of the symptoms must be either be the "D" for depressed mood or the "I" for loss of interest in activities (anhedonia).
The full symptoms are as follows:
- D for depressed mood (feelings of sadness, emptiness, hopelessness)
- S for increased or decreased sleep
- I for loss of interest in activities (anhedonia)
- G for excessive guilt or feelings of worthlessness
- E for loss of energy
- C for loss of concentration (or indecisiveness)
- A for increased or decreased appetite (or > 5% change in weight (gain or loss) in one month)
- P for psychomotor retardation or agitation (this is observable by others; it's not just an internal feeling of being "run down").
- S for suicidal ideations (either active or recurrent passive thoughts of death)
Medical/Iatrogenic Causes
- Remind ourselves to rule-out medical or iatrogenic causes (eg, hypothyroidism or any slew of commonly prescribed medications can cause symptoms of depression and suicidality).
Differential Diagnosis
Persistent Depressive Disorder
- Persistent depressive disorder (better known as dysthymia).
- Involves at least 2 depressive symptoms that last at least 2 years in duration. It's generally considered to be milder but more refractory than major depressive disorder.
Major Depressive Disorder with Seasonal Pattern
- Major depressive disorder with seasonal pattern (better known as seasonal affective disorder).
- The MDD is restricted to a season (typically winter) and that it must occur in at least 2 consecutive years (and will typically occur consistently over a lifetime). Light therapy (in addition to buproprion and other MDD treatments) is helpful in the management of this disorder.
Peripartum Onset Depression
- This mood disorder begins within 4 weeks of giving birth.
- There is often a pre-existing mood disorder.
- Symptoms range from severe depression to psychosis, called postpartum psychosis.
- A milder form, called postpartum blues, is common, which may affect up to 85% of women for the first couple of weeks post-delivery.
Bereavement
- Importantly (and contentiously) the DSM-IV established that a diagnosis of major depressive disorder couldn't be made in the setting of bereavement but the updated, DSM-5 does not include this exclusionary criteria.
- Grief-related depression can be categorized as normal bereavement or a major depressive episode depending on whether the symptoms are considered consistent with normal grief or if they extend beyond that.
Board Review
USMLE & COMLEX-USA
USMLE Step 1 / COMLEX-USA Level 1
USMLE Step 2 / COMLEX-USA Level 2
USMLE Step 3 / COMLEX-USA Level 3
Nurse Practitioner (NP)
Nurse Practitioner Licensing Exam
Physician Assistant (PA)
Physician Assistant Licensing Exam
Neurology (ABPN)
American Board of Psychiatry & Neurology (ABPN) Exam
Internal Medicine (ABIM)
American Board of Internal Medicine (ABIM) Exam