Different types of (unipolar) depression

The two most common types

MAJOR DEPRESSIVE DISORDER (Single Episode or Recurrent Episode)
It is possible to have an episode only once in a lifetime, but more commonly, there will be several episodes.

Onset: MDD may first appear at any age, but the likelihood increases in adolescence, with the peak being in the 20s. It is not uncommon to experience MDD for the first time in late life, often due to failing health and many changes.

If you have been experiencing some of the following symptoms nearly every day for at least 2 weeks, you may be suffering from Major Depressive Disorder (MDD):

  1. Persistent depressed mood, such as sadness, emptiness, hopelessness, or “down in the dumps”
    1. Some individuals may also present with complaints about bodily aches or pains, headaches, cramps, or digestive problems without a clear physical cause and/or that do not diminish even with treatment 
    2. Some individuals may also present with persistent anger (exaggerated frustration over minor matters, angry outbursts, assigning blame…)
  2. Loss of interest or pleasure in activities and hobbies; social withdrawal
  3. Significant weight changes or decreased/increased appetite
  4. Insomnia or hypersomnia
  5. Observable by others: agitation (can’t sit still; pacing; handwringing; pulling or rubbing of the skin, clothing, or other objects) or being “slowed down” (slowed speech and body movements; pausing too much before answering; speech that is decreased in volume, inflection, amount, or variety of content, or even muteness)
  6. Decreased energy, tiredness, and fatigue
  7. Feelings of worthlessness or excessive/inappropriate guilt
  8. Difficulty concentrating, remembering, making decisions
  9. Thoughts of death or suicide, suicide attempts

Keep in mind that (a) most people do not experience every symptom and that (b) it is not necessary to experience all of them in order to meet the threshold for the diagnosis of MDD. The severity, frequency, and duration of symptoms depend on the stage of the illness and vary from person to person. 

PERSISTENT DEPRESSIVE DISORDER (aka Dysthymia)
This disorder looks similar to MDD, but the duration is significantly longer. It usually presents as a chronic, low-grade depression. It is possible to have this disorder and MDD simultaneously. 

Early onset: If the disorder is first experienced before 21 years of age.
Late onset: If the disorder is first experienced at 21 years of age or older.

  • Depressed mood (sad or “down in the dumps”) for most of the day, for more days than not, for at least 2 years (and the symptoms have never been absent for more than 2 months at a time)
  • Poor appetite or overeating
  • Insomnia or hypersomnia
  • Decreased energy, tiredness, and fatigue
  • Low self-esteem
  • Poor concentration or difficulty making decisions
  • Feelings of hopelessness

Keep in mind that (a) most people do not experience every symptom and that (b) it is not necessary to experience all of them in order to meet the threshold for the diagnosis. 

It is not uncommon to have the symptoms of dysthymia for many, many years. Therefore, individuals often experience the symptoms as part of their personality (“I’ve always been this way”), rather than realizing that they may be suffering from a mood disorder. This is especially true in the case of early onset.

Additional forms of depression

  • With seasonal pattern—Popularly referred to as “seasonal affective disorder” (but is not a codable diagnosis on its own), this specifier applies when the symptoms typically begin in the fall or winter and go away during the spring and summer
  • With peripartum onset—Popularly referred to as “postpartum depression” (but is not a codable diagnosis on its own), this specifier applies when the symptoms of MDD begin during pregnancy or in the 4 weeks following delivery. Fifty percent of “postpartum depression” cases actually begin prior to delivery. Women with these episodes often have severe anxiety and even panic attacks. This is not the same as the condition commonly referred to as “baby blues,” which affects up to 80% of new mothers and is used to describe feelings of worry, unhappiness, and fatigue
  • Premenstrual Dysphoric Disorder—Popularly known as PMS, this diagnosis consists of the following symptoms (not all of them have to be present, but at least five must be present in the final week before the onset of menses, start to improve within a few days after the onset of menses, and become minimal or absent in the week postmenses):
    • Affective lability (e.g., mood swings, feeling suddenly sad or tearful, or increased sensitivity to rejection [real or perceived])
    • Irritability, anger, or increased interpersonal conflicts
    • Depressed mood, feelings of hopelessness, or self-deprecating thoughts
    • Anxiety, tension, and/or feelings of being keyed up or on edge
    • Decreased interest in usual activities
    • Subjective difficulty in concentration
    • Lethargy, easy fatigability, or marked lack of energy
    • Change in appetite, overeating, or specific food cravings
    • Hypersomnia or insomnia
    • A sense of being overwhelmed or out of control
    • Physical symptoms such as breast tenderness or swelling, joint or muscle pain, a sensation of “bloating,” or weight gain