How Common is Borderline Personality Disorder?

The American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders is the standard reference text for all forms of mental illness. It has defined borderline personality disorder as “a pervasive pattern of instability of interpersonal relationships, self-image, and affects, and marked by impulsivity beginning by early adulthood and present in a variety of contexts.”

Individuals with borderline personality disorder (BPD) suffer from emotional imbalances that impact their perceptions, thinking patterns, and behavior on a daily basis. BPD inhibits a person’s ability to maintain interpersonal relationships, be effective as parents, function in the workplace, and follow through on their hopes and dreams. The earliest symptoms of borderline personality disorder generally appear sometime during adolescence, and most BPD sufferers are diagnosed as young adults.

Until a few years ago, it was believed that somewhere between one and two percent of the adult population in the United States would suffer from borderline personality disorder during their lifetimes.

But recent evidence proves this appraisal was far too low.

In 2004-2005, researchers hired by the National Institute on Alcohol Abuse and Alcoholism interviewed more than 34,000 American adults to gather information about their encounters with mental illness and substance abuse. Participants in the Wave 2 National Epidemiological Survey on Alcohol and Related Conditions (NESARC) were questioned about their history of mental health symptoms, to determine what types of diagnosable conditions they had suffered from over the course of their lives.

Much to the surprise of the researchers, the number of people who met the diagnostic criteria for borderline personality disorder was three-to-four times greater than previous estimates.

In total, 5.9 percent of those surveyed had suffered symptoms consistent with a diagnosis of BPD. Broken down by gender, the lifetime incidence rate was 5.6 percent for men and 6.2 percent for women. Assuming these numbers are correct, it means 18 million American adults are destined to suffer from borderline personality disorder at some point during their lives, if they haven’t done so already.

While the raw numbers are significant, the discrepancy between men and women was also notable because it was far lower than expected. Historically, women have comprised about 75 percent of all diagnosed cases of borderline personality disorder, and that percentage hasn’t shown much variation over the years. The discovery that men actually developed the condition nearly as frequently as women proves that diagnostic rates are not synonymous with incidence rates, and that alternate explanations are needed to explain the huge gender gap in BPD diagnoses.

Another misconception about borderline personality disorder is that it is strictly an adult condition. However, the latest research has proven this assumption to be incorrect.

A 2008 study published in the Scandinavian peer-reviewed journal Acta Psychiatrica Scandinavica analyzed the existing evidence on adolescent BPD. According to the calculations of the study authors, about 1.4 percent of teens involved in past studies met the criteria for a borderline personality disorder by age 16, with the number rising to 3.2 percent by age 22.

Overall, there could be as many as a half-million teens suffering from early-stage borderline personality disorder, and that does not include adolescents experiencing BPD symptoms in lower numbers than required to receive a diagnosis.

The exact rates of BPD among children are not known, but few mental health professionals doubt that pre-teens can and do experience borderline personality disorder symptoms, either in response to trauma or because of a genetic predisposition (or both). Self-harming behaviors, which are a distinctive sign of BPD, are often observed in children in the 10-12 age range, and other symptoms consistent with a BPD diagnosis have been reported in even younger children.

Only some of these kids will develop full-blown borderline personality disorder when they mature, but rapid medical attention will be vital for those that do.

Here are some factors that can prevent mental health professionals from making a correct diagnosis of BPD in at least some cases where the disorder is present:

1. Lack of accuracy in patient reporting. Mental health professionals rely on in-depth interviews and questionnaires to detect the presence of mental health disorders. This approach generally produces accurate results, but the effects of a pervasive, all-encompassing disorder like BPD aren’t always easy to recognize, and many patients undoubtedly leave important details out in their self-descriptions.Overlapping symptoms between various conditions can cause confusion, which explains why BPD is frequently misdiagnosed as bipolar disorder, post-traumatic stress disorder (PTSD), adult ADHD, and other similar mental health conditions. But full, accurate reports of symptom experiences likely reduces the incidence of misdiagnosis to a significant degree, and mental health experts always face a challenge when trying to determine if the information they’ve been given is complete.
2. The arbitrariness of the diagnostic requirements. To be diagnosed with borderline personality disorder, a person must demonstrate a number of core traits or symptoms, as identified in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5).But there is an inevitable degree of randomness or arbitrariness built into such standards. If an individual experiences just a few of these symptoms intensely or in a broad range of situations, their lives might be disrupted even more than someone experiencing even more symptoms at a manageable level. Nevertheless, they would not pass the diagnostic threshold for BPD, and if they had a BPD diagnosis in the past they might now be considered “in recovery.” If borderline personality disorder exists on a continuum with varying levels of severity, its rate of incidence may still be underestimated, given the requirement that a certain set of symptoms be detected before a diagnosis can be given. Should standards ever change to include those seriously impacted by fewer symptoms, the rates of diagnosis for borderline personality disorder could rise once again.
3. A tendency on the part of mental health professionals to misidentify BPD as other conditions. In the past, when awareness of the true incidence of borderline personality disorder was lacking, many psychiatrists and psychologists were undoubtedly overlooking many legitimate cases of BPD. Based on gender discrepancy statistics, it appears men in particular were being misdiagnosed far more frequently than women. Misdiagnosis is still an issue at times, especially among men. But recent research has revealed enough details about borderline personality disorder to make it far easier for mental health experts to diagnose. Professionals are also aware that BPD is often accompanied by co-occurring mental health conditions, and they can detect the presence of multiple disorders by making subtle distinctions between symptoms. Despite progress, the problem of misdiagnosis has not been completely solved. Mental health professionals are not perfect, and there is no way to eliminate the human element from the diagnostic equation.But if patients (and their family members) provide clinicians with thorough and accurate reports about the symptoms experienced, people suffering from BPD have a good chance of receiving a correct diagnosis the first time they seek help. Accurate diagnoses are quite important, since treatment regimens appropriate for other disorders usually won’t eliminate the symptoms of BPD.

Treatment programs for borderline personality disorder are psychotherapy-centered, with medications, education, life skills training, and holistic healing techniques frequently added to the mix.

Fortunately for BPD sufferers, their chances for recovery are among the highest for all mental health disorders. Studies show that most individuals with BPD (70-90 percent) can expect significant and lasting improvements after a few years of steady involvement in ongoing treatment regimens.

While the lifetime incidence of borderline personality disorder is significantly higher than previously believed, the outlook for those who suffer from it is excellent, if they seek treatment and remain dedicated to the healing process. It can be especially helpful for BPD sufferers to begin treatment in residential inpatient facilities, where they can spend the vital first few weeks of their recovery immersed in a supportive care environment.

Despite the changing estimates, the real incidence of borderline personality disorder has likely been higher than suspected for a long time. The upward trends are more a reflection of improvements in diagnostic techniques than anything else: mental health professionals now know BPD is quite common, and they are better prepared to offer effective, evidence-based healing services to BPD sufferers who come to them seeking assistance.