20 percent of all psychiatric inpatients have BPD, as do 10 percent of all mental health outpatients according to the American Psychiatric Association. Their characteristics of low functioning borderlines include:
1. They acknowledge they have some behavior problems (not necessarily BPD, however)
2. They cope with pain through self-destructive behavior, such as self-injury and actions that put them in harm’s way. The term for this is “acting in”
3. They (often desperately) seek help from the mental health system. Some are hospitalized for their own safety. They may often become very attached to their professional caregivers
4. They have a difficult time with daily functioning and may even be disabled. This is called “low functioning”
5. If they have overlapping (“comorbid) other disorders, they tend to be the kind that require intensive professional treatment, such as Bipolar, Clinical Depression, or an Eating Disorder
6. Family members’ greatest challenges are keeping their loved one alive and functioning. Other concerns might be their inability to, earn their own living and adequately parent their child.
In a discussion on BPDFamily.com, Randi Kreger, co-author of Stop Walking on Eggshells, says the situation with high functioning borderlines will look more like this:
"1. Denial is their primary characteristic. They disavow having any problems and see no need to change. Relationship difficulties, they say, are everyone else’s fault. If family members suggests they may have BPD, they almost always accuse the other person of having it instead. (This is why I strongly advise non-BPs to leave this disclosure to a trained professional)
2. They cope with their pain by raging outward, blaming and accusing family members for real or imagined problems (“acting out”)
3. They refuse to seek help from the mental health system unless someone threatens to end the relationship. If they do go, they usually don’t intend to work on their own issues. In couples therapy, their goal is often to convince the therapist that they are being victimized
4. They may hide their low self-esteem behind a brash, confident pose that hides their inner turmoil. They usually function quite well at work and only display aggressive behavior toward those close to them (high functioning). But the black hole in the gut and their intense self-loathing are still there. It’s just buried deeper
5. If they also have other mental disorders, they’re ones that also allow for high functioning such as Narcissistic Personality Disorder (NPD) or Antisocial Personality Disorder (APD). (These mostly appear concurrently in men—especially APD)
6. Family members’ greatest challenges include coping with verbal abuse, protecting children, trying to get their family member to seel treatment, and maintaining their self-esteem and sense of reality. Partners, especially, are in relationships with Cluster Two BPs. "