Borderline Personality Disorder (BPD) Misdiagnosis

Learn Why BPD Misdiagnosis Happens So Often

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Borderline personality disorder (BPD) misdiagnosis appears to be common. You may be surprised to learn, however, that even though BPD occurs as often as schizophrenia and bipolar disorder, affecting about 14 million Americans, many people who actually have BPD are misdiagnosed at first. 

In one study, researchers found that nearly 40% of people with BPD in their study sample had previously received a misdiagnosis of bipolar disorder.

What's the Biggest Reason Why BPD Is Misdiagnosed So Often?

Probably the main reason is that BPD is seldom a person's only mental health problem. Instead, it often occurs together with other mental health problems such as depression, bipolar disorder, anxiety disorders, substance abuse, and other types of personality disorders.

For example, more than 50% of people diagnosed with BPD also have major depressive disorder.

As a result, the symptoms of BPD may not be recognized at the time a person is diagnosed with another mental health problem, such as an anxiety disorder.

What Other Factors Can Cause BPD Misdiagnosis?

Additional reasons why BPD misdiagnosis occurs include the following.

The Symptoms Do Not Appear. BPD is unusual in that many people who have it don't "show" their symptoms, such as anger, instability, and impulsiveness, in the early stages of relationships with others, including mental health professionals. So the symptoms of BPD don't appear and can't be diagnosed.

Why does this happen? The person isn't "hiding" the BPD symptoms. They don't emerge early in therapy because they typically appear only in close or intimate relationships, which take time to develop. 

The Person Drops Out of Treatment, Perhaps Repeatedly. People with BPD tend to drop out of treatment at fairly high rates. If a person with BPD is not showing symptoms early in therapy for another mental health disorder and then chooses not to continue treatment, the therapist has no opportunity to make a BPD diagnosis. This may happen over and over if a person with undiagnosed BPD repeatedly goes from one therapist to another without staying long enough for the BPD symptoms to appear.

BPD Symptoms Are Vague and Overlap With Other Diagnoses. BPD symptoms such as anger, shame, a feeling of emptiness, and suicidal thoughts are common in other mental health disorders. So a person may be correctly diagnosed with one mental health disorder (for example, major depression) that has some of the symptoms of BPD, but the co-diagnosis of BPD may be missed. 

Preventing BPD Misdiagnosis and Getting the Treatment You Need

As you can see, correctly diagnosing BPD can be unusually difficult. If you think you or a loved one may have BPD, it's important to ask the right questions and find a mental health professional with a lot of experience recognizing and treating it.

Borderline Personality Disorder Discussion Guide

Get our printable guide to help you ask the right questions at your next doctor's appointment.

Mind Doc Guide

If you're not receiving treatment for your mental health symptoms, look for a therapist who's experienced in diagnosing BPD as well as other mental health disorders. This Find a BPD Therapist website can help.

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Article Sources
  • Ruggero CJ, Zimmerman M, Chelminski I, Young D. "Borderline Personality Disorder and the Misdiagnosis of Bipolar Disorder." Journal of Psychiatric Research, 44(6):405-408, 2010.
  • Zanarini MC, Frankenburg FR, Dubo ED, Sickel AE, Trikha A, Levin A, Reynolds V. “Axis I Comorbidity of Borderline Personality Disorder.” American Journal of Psychiatry;155(12):1733-1739, 1998.
  • National Education Alliance for Borderline Personality Disorder (2016). About BPD.