Recently Diagnosed Personality Disorder NOS…What Does That Mean?

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Reader’s Question

I’ve recently been diagnosed with Bipolar l (Mixed) and a Personality Disorder NOS. I’m confused on what the Personality Disorder (NOS) actually means. What is the difference between Borderline Personality Disorder and a Personality Disorder?

Psychologist’s Reply

In current clinical practice, recognized mental health conditions and disorders are grouped by a general category — then by specific clinical diagnosis. Under “Mood Disorders” for example, we have Major Depression, Dysthymia, Bipolar Disorder (several types), Cyclothymia, and even Mood Disorder NOS. The “NOS” means “Not otherwise specified”. Using NOS is the clinician’s way of saying there is a diagnosis in this general category but I don’t have enough information to make a specific diagnosis yet.

“Personality Disorders” is one of the general categories. This category is often given to individuals who have a long history of personality, behavior, emotional, and relationship difficulties. This group is said to have a “personality disorder” — an enduring pattern of inner experience (mood, attitude, beliefs, values, etc.) and behavior (aggressiveness, instability, etc.) that is significantly different from those in their family or culture. These dysfunctional patterns are inflexible and intrusive into almost every aspect of the individual’s life. These patterns create significant problems in personal and emotional functioning and are often so severe that they lead to distress or impairment in all areas of functioning. (Source: DSM-IV.)

In my observation, Personality Disorders often have core personalities of self-preoccupation, insensitivity to others, a refusal to accept personal responsibility (it’s always someone else’s fault), and a tremendous sense of entitlement. Personality Disorders are further grouped into three “clusters”. Cluster A are individuals who might be considered odd and eccentric — Paranoid Personality Disorder is one of these. Cluster B are individuals who are dramatic, emotional, and erratic. Cluster C are those who have a personality characterized by anxiety and fearfulness.

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Borderline Personality Disorder is in the Cluster B group and would suggest a long history of intense/unstable relationships, an unstable self-image, fears of abandonment, severe problems with impulsivity, frequent suicide gestures/threats, self-mutilating behavior, intense mood changes, and other symtoms.

The diagnosis of Personality Disorder NOS is a way of saying that while you are currently being treated for Bipolar Disorder, the clinician suspects you may have long-standing personality features that may complicate your treatment and/or recovery. The NOS suggests that a full pattern of a specific personality disorder may not be present. You may have a few symptoms of one type, a few of another type, etc.

In your treatment, while this sounds like a bunch of labels, it’s very important. Treatment for Bipolar Disorder focuses on emotional and social stability — preventing both depressive and manic episodes. When treating individuals with personality disorder features, medication noncompliance is higher. Cluster B folks are more difficult to treat due to their emphasis on excitement and emotional drama. If you have Borderline Personality Disorder features, there is an additional risk for self-harm.

In summary, you will need a combination of psychiatric treatment for the Bipolar Disorder and counseling/therapy to address the Personality Disorder features. While being labeled a “personality disorder” is uncomfortable, once you recognize the personality pattern you are better equipped to understand how and why situations in your life become so difficult. We have also developed specific types of treatment for many of the personality disorder symptoms. I’d recommend discussing additional treatment for these personality features.

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