Individuals with borderline personality disorder (BPD) frequently suffer from other psychiatric disorders as well. When this occurs, they have a “co-occurring” or “comorbid” disorder. The reason borderlines are particularly vulnerable to co-occurring disorders may be partially due to their particular genetic makeup.
In many instances, the comorbid disorder is diagnosed accurately, but the clinician misses the borderline diagnosis. This is unfortunate, because it is very difficult to effectively treat the other disorder if the BPD is not treated appropriately. Also, in order to effectively treat the BPD, any comorbid disorders must be treated as well. Treating the comorbid disorder properly can help speed up the treatment of BPD as well.
The disorders that most commonly co-occur with borderline personality disorder include mood disorders (depression and bipolar disorder), substance abuse, posttraumatic stress disorder (PTSD), eating disorders (particularly bulimia), attention deficit hyperactivity disorder, and anxiety disorders. Let’s look at each of these more closely:
Major Depressive Disorder
One of the characteristics of many people with BPD is mood swings. They can rapidly go back and forth between an upbeat, “euphoric” mood, to a dark, angry, irritable “dysphoric” mood. But some individuals with BPD meet the criteria for major depressive disorder (MDD) as well. The symptoms of MDD include feeling sad or empty most of the time, apathy, low energy, difficulties concentrating or making decisions, thoughts of suicide, sleep and appetite disturbance, agitation or restlessness, and feelings of hopelessness, guilt, and worthlessness.
Borderline individuals already struggle with a sense of being inherently bad. Agitation and irritability are also very common. Suicidal ideation is a frequent problem, with around 10% of individuals with BPD committing suicide.
A significant percentage of individuals with BPD have a comorbid substance abuse disorder. Their particular vulnerability may be due to several different factors:
• A family history of substance abuse or addiction (not uncommon in the chaotic childhoods of many borderlines) – which could mean there is a genetic predisposition and / or it is a learned coping mechanism.
• Their tendency to be impulsive and engage in reckless or self-destructive behaviors.
• A desire to self-medicate and numb the frequent pain and distress that they feel.
Alcohol and drugs can be especially dangerous in the hands of someone with BPD. They may cause any combination of the following:
• Intensify feelings of rage and other negative emotions
• Increase the risk of self-mutilation and suicidal thoughts and behaviors
• Increase impulsivity
• Worsen judgment that is already impaired in stressful situations
• Cause further damage to relationships that are already unstable
• Intensify mood swings
• Trigger or increase paranoid ideation and transient psychotic symptoms
A high percentage of individuals with BPD also have PTSD (posttraumatic stress disorder). Many borderline individuals have backgrounds that include childhood sexual abuse and / or physical abuse. PTSD is triggered by traumatic experiences, and can develop at any stage of life. Since BPD typically begins to develop in childhood, the frequent comorbidity of these two disorders is not surprising. The maladaptive coping skills typical of BPD often develop as a way of coping in an unpredictable, chaotic environment.
Individuals with both disorders often experience trauma much earlier in life than those who have PTSD only. However, the rocky relationships, impulsivity, and recklessness that are typical of BPD can also increase the risk of traumatic events (e.g. car accidents and sexual or physical assaults) that may cause PTSD to develop.
Eating disorders are not uncommon in individuals with BPD. Anorexia nervosa and bulimia nervosa are the two primary eating disorders found in the DSM, but bulimia is the one that is most often co-occurs with BPD. Childhood trauma is frequently found in the histories of people with eating disorders as well as people with BPD. The impulsive, self-destructive tendencies of borderlines may also make them particularly vulnerable to developing an eating disorder.
Attention deficit hyperactivity disorder frequently co-occurs in borderline individuals, affecting nearly 1 out of every 4. Like BPD, people with ADHD often struggle with impulsivity. One of the dilemmas with treating someone with BPD and ADHD is that ADHD medications can make borderline symptoms worse.
Typical ADHD medications (e.g. Ritalin) are stimulants. The effects of these medications on a person with BPD may lead to more impulsive, aggressive behaviors and heightened emotional reactivity. If the ADHD symptoms are mild, behavioral treatment without medication may be sufficient. If medication is required for the ADHD symptoms, adding an antipsychotic medication at a low dose may help offset the negative stimulant effects.
Anxiety and Panic Disorders
Many borderline individuals also have an anxiety disorder, including panic disorder. They may be particularly vulnerable due a childhood background of trauma, chaos, and / or conflict. Children raised in such environments are more prone to developing an anxiety disorder. Also, the maladaptive coping skills typical of BPD may be utilized to help manage the underlying anxiety that they often feel.
Since substance abuse is rampant amongst the borderline population, the use of benzodiazepines to treat anxiety should be done with great caution. This is because benzodiazepines (e.g. Xanax and Valium) are highly addictive medications. Since they have a strong sedative effect, these medications could be easily abused by someone with BPD who is attempting to self-medicate and numb their intense, emotional pain.
Other Personality Disorders
Many people with BPD also meet the criteria for a second personality disorder. Personality disorders that often co-occur with BPD are narcissistic personality disorder and schizotypal personality disorder. Individuals with antisocial personality disorder also frequently display traits that meet the criteria for a comorbid diagnosis of BPD.
Narcissistic personality disorder, antisocial personality disorder, BPD, and another personality disorder known as histrionic personality disorder are all part of the “Cluster B” group of personality disorders. Overlapping traits include manipulative behaviors and impulsivity. Histrionics and borderlines both tend to engage in attention-seeking behavior and emotional displays that can quickly shift.
People who have both BPD and NPD are typically very destructive when it comes to relationships. Extreme fear of rejection, intense emotional displays, lack of empathy for others, and manipulative behavior make living with these individuals very difficult.
Schizotypal personality disorder traits that overlap with BPD include ideas of reference and paranoid ideation. Odd or eccentric behaviors and beliefs, and excessive social anxiety are characteristic of schizotypal individuals.
A fair number of individuals with BPD are also diagnosed with bipolar disorder. Both disorders involve mood swings and erratic behaviors, although the mood patterns are very different. While many people do meet the criteria for both disorders, inexperienced clinicians may misdiagnose bipolar disorder in someone with BPD, and vice versa. Having both disorders is particularly challenging.
Borderline personality disorder by itself can wreak significant havoc in a person’s life. Frequent crises, intense emotions that are difficult to manage, job losses, and a long history of unstable relationships can make life very difficult. To have an additional disorder only compounds the challenge many times over.
If you or someone you love have both BPD and another psychiatric disorder, it is more crucial than ever to get the appropriate treatment for both disorders. That being said, treatment providers must be particularly cautious to make sure that the treatment for one disorder does not negatively impact the other disorder. Finding the right balance is really important in order for treatment to be effective. Also, finding ways to manage stress and minimize it as much as possible will help keep symptoms of both disorders from spiraling out of control.