So I think it’s pretty easy to see how Borderline Personality Disorder and Bipolar disorder can look similar on the surface. Once you look a little deeper though those similarities start to look a lot less alike though. I’ve been debating how to handle the differences. Since I just did the similarities should I now look at those and show how they’re not actually so similar? And then talk about the real heart main differences that we don’t share in common? But I think it’s more important to understand that these two disorders are really two very different things. So I’ll debate the details later. Let’s cut to the chase and get to the heart of the matter now.
Here’s the thing. While both BPD and Bipolar revolve around the expression of fluctuating moods, Bipolar Disorder is a neurological disorder. It’s hardwired. Environmental factors do absolutely influence the initiation and expression of bipolar disorder and bipolar episodes, but not in the same ways that they do with Borderline PD. With BPD our environment or something relating to it, and the people within our environment (if not ourselves) are what trigger us nearly 100% of the time. It can happen randomly and at any given moment depending on the stimuli we face. With Bipolar manic-depressive cycles are not random though that doesn’t mean they’re predictable. With Bipolar there does tend to be a cycle or pattern to the periods of mania and depression that are experienced (unless a person experiences rapid-cycling phases, then it’s a little more difficult to distinguish and more dependent on stress response). This is dependent on the person’s particular brain chemistry. If left untreated, these cycles can increase in frequency over time. How a person reacts during these periods though, can be unpredictable depending on what goes on.
There are many theories and a lot of research into the neurobiology involved in Bipolar Disorder.
“The neurobiology of bipolar disorder is associated with alterations in central nervous system function from the level of large-scale brain circuits to intracellular signal transduction mechanisms. Because of the broad spectrum over which these abnormalities appear, the causative effects are most likely present in the lowest common denominator of all of these systems. Functional imaging (fMRI) focus on large-scale changes in both cerebral blood flow and metabolism. These studies showed that bipolar-depressed patients had significantly lower cortical metabolism than either controls or patients with unipolar depression. Both mania and depression are characterized by profound global changes in brain function. These state changes are manifest at multiple levels in the nervous system. There are also alterations in brain chemistry and neurochemical changes present in people with bipolar disorder. These neurochemical changes are evident in virtually all levels of the central nervous system.” 
The list of neurobiological systems affected doesn’t stop here either. But as you can see the cause of this disorder is easily identified as being obviously biological in natural.
As opposed to BPD which does have some biological roots, but is equally influenced by environmental factors as well. Also, as I’ve talked about previously in articles discussing the neurobiology of Borderline Personality Disorder, the affected areas of our neurochemistry occur in entirely different locations.
The term ‘bipolar’ can also be a little misleading because it indicates that individuals are always either manic or depressed and that these states are at opposite ends of a spectrum. The reality is much more complex though. While the manic and depressed states do go well beyond the normal functioning ranges for most people they span a range of intensity and can even be mixed and felt at the same time. Not only that, but between times of mania and depression it’s not uncommon to have periods of ‘normality’ when a person with BD is neither manic nor depressed.
As opposed to someone with BPD, we’re just sort of always the way we are… which is to say, kind of unpredictable (without treatment!) and always up, down, in between, mixed up, angry, okay, happy, sad, well, you get the picture.
My point is the:
#1 Main Difference between BPD and Bipolar is Neurological Brain Chemistry. Bipolar is a brain disorder where BPD is an emotional disorder.
Bipolar - is an Axis-1 Mood Disorder
Borderline Personality - is an Axis-2 Personality Disorder
Simple. As. That. Doesn’t matter how it looks. Doesn’t matter how it appears on the surface. What matters is what’s actually going on inside our heads. And that’s a whole different mix of chemical-emotional combinations.
|They both suck.|
Don’t get me wrong, every single person in existence (with the exception of people that have no empathic or emotional affect) are effected by their environment. But the extreme shifts in mood that Bipolar experience are due to/enhanced by chemistry. The moods in people with BPD are more dependent, either positively or negatively, on what's going on in their life at the moment and our maladaptive emotional/behavioral responses. Anything that might smack of abandonment (real or perceived is a major trigger, etc.
That’s not to say that one or the other is better or worse to have. They both suck huge monkey balls. For those who have them, and for the loved ones that get to live with those of us that have them, but they are different things. This is an important distinction to make because it defines the #2 difference.
#2 Difference Between BPD and Bipolar Disorder: Treatment
Bipolar – The first course of treatment for Bipolar is typically a mix of medication. The second course of treatment, if it’s chosen at all, is cognitive therapy. There are many, many medication types and classes used, tested, and proven useful in the treatment of Bipolar Disorder. This doesn’t actually mean it’s easy to find the proper combination of medication for a person, and medication often has to be adjusted depending on the time of year, but as it is a disorder of chemistry, it is more likely to be chemically treated. It’s also widely accepted that once a good medication regime is found a positive response is very likely to be achieved.
BPD – The first course of treatment for BPD is cognitive therapy (DBT, CBT, etc). The second course of treatment, if chosen at all, is medication. If medication is pursued, it’s never chosen to treat BPD as a whole because there is no medication that treats BPD as a whole. Medication is chosen to treat specific symptoms of BPD. The most important thing is to learn how to cope with our maladaptive behavioral coping mechanisms and replace them with constructive adaptive ways of coping. The course of medication and therapy is likely to take months, even years longer achieve similar healthy results.
Both groups are often reluctant to seek help and may be resistant to medication. Also, both groups have a tendency to stop taking prescribed medications when they begin to feel better which often leads to relapses.
#3 Difference Between BPD and Bipolar Disorder: Cycling
Bipolar – People with Bipolar disorder cycle in periods for extended periods of time. Even with rapid-cycling bipolar these periods can last for days.
BPD – People with BPD cycle through moods much, much more quickly; often several times a day. Hell, often several times an hour.
#4 Difference Between BPD and Bipolar Disorder: Mood Swings
Bipolar - People with bipolar disorder swing between all-encompassing periods of mania and major depression.
BPD – As Marsh M. Linehan says, in people with BPD, the mood swings are more distinct. The mood swings typical in BPD are specific to the particular situation. She says, "You have fear going up and down, sadness going up and down, anger up and down, disgust up and down, and love up and down."
Now! That doesn’t mean a manic phase encompassing a very irritable, angry person with Bipolar Disorder is going to look much different than the nasty, bickering bitchiness of pissed off Borderline, however maybe something about April is the time of year when some with Bipolar Disorder starts to get manic, whereas with BPD, you might have just triggered an insecurity or done something we took offense too that spun our emotions out of control. They can look the same, but the causes are different.
#5 Difference Between BPD and Bipolar Disorder: Depression
Bipolar – Depression is a guarantee. It’s one half of what puts the ‘bi’ in bipolar. It occurs cyclically after a period of mania or euthymia (normal mood) and can often be the “normal” mood.
BPD – Depression is not a guarantee. While it is very common that someone with BPD will also suffer from depression at some point, and nearly 50% of us with BPD have co-morbid Major Depressive Disorder, it is not necessarily a part of the package. If it is a part of the package, it is not necessarily cyclic. Depression can be triggered for any number of reasons, or be your baseline level of mood existence. Or if you happen to be like me, you exist in depression and get even more depressed at a particular point during the year. So it’s like the worst of both worlds all wrapped up together ::head desk::.
… That’s enough for today. There’s more though! Tomorrow I’ll debunk some of those “similarities”.