Mood Swings – What Causes Them?

2014-05-09_9-17-09What causes mood swings? What do we think about when someone says their mood has been “up and down?”Among the most common causes of mood shifts are the following:

  1. A mood disorder such as bipolar, or an atypical depression.
    1. Bipolar as a cause is obvious, but an atypical depression can also be associated with mood swings. In the case of bipolar the swing may be from an energized state (called hypomania, or a little mania) into depression or vice versa. In the case of an atypical depression, the swing is most often from slightly depressed to severely depressed.
    2. Atypical depression is a kind of depression associated with marked sensitivity to criticism, sleeping too much when depressed and often gaining weight when depressed.
  2. Normal ups and downs in mood that all of us experience.
    1. See below for a brief discussion about “what is normal” – which could take up an entire post.
  3. A personality disorder such as borderline personality disorder.
    1. “Personality disorders” refer to a group of psychiatric conditions that begin in childhood (usually) and tend to be fairly persistent.
    2. Borderline personality disorder is usually linked to mood instability, feeling uncertain about one’s identity (who am I?), severe reactions to threatened or actual relationship losses (abandonment), and a pattern of difficulty generally dealing with distress.
  4. A disorder related to trauma, such as post-traumatic stress disorder (PTSD).
    1. PTSD is a chronic condition that can develop after experiencing an event in which there was a serious threat of violence or actual violence.
    2. The “mood swing” with PTSD is a swing into a state of sympathetic nervous system activation (the “fight or flight” state).
    3. Irritability and anxiety are the predominant mood symptoms.

Often teasing apart the causes of mood swings is difficult and requires a careful history.  In many cases the causes may only become clear with experience and perhaps careful mood charting.As if that wasn’t complicated enough, it is quite possible for a person to have more than one type of mood swing.  Someone with bipolar can also have a borderline personality disorder.  

We recently gave a presentation on the relationship between borderline personality and bipolar at the University  of California, San Francisco’s Mood Disorder Clinic.  In essence, there is an increased incidence of bipolar in people with borderline, and an increased incidence of borderline in people with bipolar.  

In our experience many people with bipolar who also have borderline personality had traumatic experiences in childhood. The most common scenario is that the person had a bipolar parent whose mood swings were associated with violence towards the child. We know that childhood violence can lead to borderline personality. At the same time, they inherited the genes from their bipolar parent and so have bipolar disorder as well as borderline personality. 

How can one distinguish between bipolar and borderline mood shifts?

  • Bipolar mood swings tend to be less clearly linked to stressful interpersonal events, tend to be somewhat more gradual, often happening overnight or over the course of several hours.  And also follow a characteristic pattern in terms of duration of an episode and how those episodes tend to end.
  • Borderline mood swings are usually associated with some interpersonal stress or conflict, the mood shifts suddenly around the time of that event, and in an extreme fashion.  And the mood shift is almost always down into depression and anger or anxiety.

Post-traumatic stress disorder can also be associated with sudden, triggered mood symptoms.  Here the pattern is usually of anxiety, irritability and activation symptoms such as racing heart and shaky hands or shortness of breath.  Again there is an event, but in this case the event is somehow linked to a traumatic experience in the past.  Perhaps a reminder of that experience, or a similar kind of event (seeing a film about a rape when one experienced a rape in the past).  A PTSD triggered anxiety / mood state can last for quite a while.

Normal mood variation is similar in some ways to borderline or bipolar mood variation, but much less extreme. It should not be associated with significant impairment in function. And people who know you shouldn’t feel that your reactions are surprising or extreme.