Borderline Personality Disorder (BPD) and Dependent Personality Disorder are other conditions that often co-occur with depression. In BPD, a person experiences mood swings that are caused by a fragile, developmentally-delayed self-concept and identity. People with borderline personality disorder have a tendency to view relationships, people, and situations in a very simplistic and high contrast fashion- as all good or all bad, but not a mixture of the two (much as young children do). Their self-concept is fragile in part because they have difficulty tolerating a complex representation of people, places or things as capable of being both good and bad simultaneously. Instead, they gravitate towards developing more pure, simple (and unrealistic) judgments about people, places or things (e.g., as either all good or all bad). In addition, they try to discount or ignore evidence that would "contaminate" their simple and singular vision. When contradictory evidence of "badness" about something or someone who is seen as "good" becomes overwhelming, a person with borderline personality disorder may suddenly reverse their judgment and proclaim that the thing or the person is now all bad. By shifting their perception from good to bad or vice versa in this manner, people with Borderline Personality Disorder people maintain their pure, idealistic vision of the world and its contents. Borderline polarization of judgments is thus a sort of self-protective measure.
Depression in the context of BPD seems to be brought on when people's perception of themselves change in response to changing social circumstances. For example, a person with BPD might shift her views about her place within a new family after marriage based on her interactions with various family members. If she perceives all of her interactions with family members to be completely negative, she may come to view herself as "all bad." Feelings of worthlessness and hopelessness can create other symptoms of depression (being depressive symptoms themselves). Of course, it could just as easily go the other direction, with the woman in our example determining that all of the family members themselves are "all bad." The point is that people with borderline personality disorder are prone to make exaggerated judgments concerning themselves and others, which can set them up for depression, or anger, or both.
Individuals with Dependent Personality Disorder demonstrate a strong emotional need to be cared for which results in their acting in an overly passive, submissive, and clinging manner. Individuals with this disorder may have difficulty making everyday decisions such as deciding what clothes to wear to work, disagreeing with others (especially with those on whom they are dependent), initiating projects, or taking initiative in other situations (e.g., interpersonal). In addition, people with Dependent Personality Disorder are often so fearful of losing their source of nurturing and support, that they may tolerate harmful relationships (e.g., those characterized by emotional and physical abuse). Thus, the tendency of a person with Dependent Personality Disorder towards low self-confidence and self-esteem, combined with their sense that they would be devastated about losing a relationship upon which they are dependent, can set these individuals up to experience depressive symptoms. (For more information on Personality Disorders, click here to read our article).
Premenstrual Dysphoric Disorder
Premenstrual Dysphoric Disorder, or PMDD (formerly known as "late luteal phase dysphoric disorder") is another disorder that can be confused with a Major Depressive Episode. PMDD is characterized by a depressed or labile (changeable) mood, anxiety, irritability, and anger coinciding with (occurring approximately one week before) the menstrual cycle. Symptoms are often severe enough that they interfere with work and social functioning. For example, women who routinely must take a few days off from school or work during this period may have PMDD. PMDD is a distressing and disabling condition that requires medical treatment, and is more severe than the more common and milder premenstrual syndrome (PMS). Typically, PMDD symptoms subside a few days after the onset of menses.
Although Major Depression and PMDD symptoms are similar, their causes are different. In particular, the timing of Major Depressive Disorder is not related to reproductive cycles. PMDD is clearly linked to a woman's menstrual cycle and is caused either by a hormonal imbalance or the brain's inability to correctly interpret hormonal signals.
As the name implies, Schizoaffective disorder is characterized by a combination of the psychotic symptoms characteristic of schizophrenia and an affective or mood disorder. Historically, there was a debate about whether this disorder was a subtype of schizophrenia or a type of mood disorder. Now, the DSM places this disorder in the same diagnostic group as Schizophrenia.
People with Schizoaffective Disorder have delusions, hallucinations, and/or odd speech and behavior (the psychotic symptoms) as well as a period of time where they also show symptoms characteristic of Major Depression or Bipolar Disorder (e.g., major depressive, manic or mixed mood episodes). People with Schizoaffective disorder also have significant impairment in daily life (including work, interpersonal relationships, and the ability to take care of themselves).
Determining whether someone has Major Depression with psychotic features or Schizoaffective disorder can sometimes be challenging. The main difference is that the delusions or hallucinations accompanying Schizoaffective Disorder must occur for at least two weeks in the absence of any mood symptoms. If psychotic symptoms are tightly linked to mood symptoms and always co-occur, then the Major Depression diagnosis is likely more fitting.
As we have suggested, the overlap of physiological issues and illnesses, substance abuse, and other mental disorders makes diagnosing Major Depressive Disorder complicated. The assessment and diagnosis process is often painfully slow, and the wait can seem interminable to people who are suffering from depressive symptoms and want fast answers. Coming up with a proper diagnosis takes time, however. To be as accurate as possible, a clinician needs to be certain that no other medical conditions are causing symptoms, that the patient is sober for a specified length of time, and that other mental illnesses have been ruled out as potential causes of depressed mood.
We mentioned this before, but it is worth reiterating that even though the diagnosis period may seem to take forever, getting the diagnosis right is important, even vital. Diagnoses point directly to treatment selection, and different diagnoses require specific types of therapy. If the diagnosis is incorrect, a person may receive an inappropriate treatment that can cause additional suffering (either because they experience a longer period of time where they are not getting better, or because they are actually worse due to treatment).