It's possible.
One diagnosis is from a different theory in psychiatry than the other.
Personality disorders are diagnosed by behaviors.
The behaviors by themselves can be normal- it's when they interfere with "normal function" they become a problem.
Every one has dozens of them, and they are usually "self protection" behaviors.
Example (
avoidance associated with avoidance personality disorder):
- A salesman comes to your front door, and you pretend to be away. OK
- You don't pay your bills, but it's because you don't want to deal with people, not because you don't have money. NOT OK
Example (
splitting associated with borderline personality disorder):
- You drink, smoke, and cuss up a storm, but are an entirely different person in church. OK
- You love your spouse very much when nearby, but either hate or are indifferent to them when around others. NOT OK
So how is SP and AvPD not the same disorder?
That's just not known yet, but there's evidence for both arguments.
Personally, I think they are similar, but different.
One is what we feel, the other is what we do, and there's nothing that forces those to "match".
This is where the confusion comes in, and it's mainly from "social situations" and "interpersonal relationships" being included in the DSM-iv criteria for diagnosis for AvPD.
However, anything can cause avoidant behavior- spiders, heights, driving, etc...
Most phobics avoid those situations.
I don't think someone scared of spiders will have problems paying their bills (especially the bug man), so there's little dysfunction.
This isn't the case with a social phobia- almost everything we do requires some human contact.
Bills don't get paid on time, jobs are lost, and so on.
That's a serious problem, and meets the "stress and impairment" requirements of a personality disorder.
If society required contact with spiders, then you would see AvPD "attached" to arachnophobia.
There are other anxiety disorders that are "people based"-like agoraphobia and performance anxiety.
AvPD is often found in those persons, as well.
Conversely, social phobia can ignite other personality disorders besides AvPD.
Finally, there's still the "tortoise and squirrel" effect.
Social phobia and AvPD come from different theories, and are classified as such (axis I vs. axis II).
A squirrel (axis I) is going to have a different view of a tree than a turtle (axis II).
That makes things confusing, even before other trees are added to the forest.
Sometimes the squirrel will have a better view, sometimes the turtle will.
You have to go by what they
both tell you, instead of one or the other.