Bipolar Disorder And Autism Spectrum Disorder: What Is The Connection?

Autism is a neurological difference that impacts the way in which a person thinks, behaves, and relates to other people. Bipolar disorder is a mood disorder that leads to a pattern of extreme mood swings, from depressive periods to high-energy manic phases.

Look at the fifth edition of the diagnostic and statistical manual of mental disorders, which clinicians use to diagnose both, and you'll see they're featured in completely different chapters. Autism and bipolar disorder initially seem to have almost nothing in common — but we all know that first impressions can be deceiving. 

Let's get the basics out of the way: What are autism and bipolar disorder?

Autism spectrum disorder is a lifelong neurological condition characterized by:

• Differences (the diagnostic manual, the DSM-5, uses the term "deficits") in social communication and interaction. These can include trouble understanding and applying the unspoken rules people without autism have for spoken and nonverbal communication, and challenges in initiating and maintaining social relationships. 
• What the DSM-5 describes as "restricted, repetitive patterns of interest, behavior, and activities". A strong need for sameness and routine and deep passions for certain subjects often to the exclusion of almost everything else are part of this. So are distress when faced with change, "stimming" (repetitive motor movements or speech), and an over- or under-sensitivity to stimuli like light, sound, pain, temperature changes, and smell. 

Autism can be diagnosed with and without speech and intellectual impairments. While people on the spectrum may need varying levels of support to function well in a world that they struggle to understand and that certainly doesn't understand them, autism is, at heart, a divergent neurological profile — an inherent part of a person's identity. 

Bipolar disorder, formerly known as manic depression, is an entirely different beast. A complex and debilitating mood disorder, it's core features are periods of mania or hypomania that alternate with periods of depression. 

During a manic episode, someone with bipolar disorder may experience super-human bursts of energy and put all their efforts into an often risky goal, coming up with a never-ending stream of novel and unusual ideas. They may experience feelings of grandiosity and invincibility, and feel like they hardly need any sleep. While experiencing a manic episode, a person may feel euphoric — but they can also be rather irritable. People with bipolar disorder may feel somewhat detached from the rest of the world during this time.

A hypomanic episode is a slightly less severe manic episode. Depressive episodes are, meanwhile, characterized by the same symptoms as major depressive disorder — things like extreme sadness, low mood, little appetite, a loss of interest in activities a person previously found meaningful, and feelings of worthlessness and guilt. 

To be diagnosed with bipolar disorder, which has four distinct subtypes, a person has to "cycle" through both (hypo)manic and depressive episodes unless they are receiving treatment.

What are the similarities between autism and bipolar disorder?

A high-energy autistic person who incessantly talks about their passions while displaying unusual social behaviors and stimming — flapping their hands, spinning around, clicking a pen, or repeating a phrase over and over again — may, to outsiders, look like someone with bipolar disorder going through a manic episode. Even when they're just being their normal self. There is, therefore, some overlap in symptoms.

Misdiagnosis may be a risk, so it's important for clinicians to establish whether they are seeing a pattern that suggests bipolar disorder, or they are simply looking at autistic behaviors. Differentiating between the two requires two main ingredients. Firstly, manic episodes represent a drastic change in mood and behavior — someone who consistently behaves the same way over long periods of time isn't manic. Secondly, to be diagnosed with bipolar disorder, depressive episodes must also be present.

Coming to a correct diagnosis is essential. Autism is, after all, a lifelong neurological difference that isn't going anywhere and that can't and doesn't need to be treated with medications. Bipolar disorder cannot be cured, but is manageable with mood stabilizers to enable patients to live a life free from the emotional rollercoaster its symptoms drag them onto. 

"Treating" a person who is just autistic with these drugs is detrimental, just like failing to treat someone who is autistic but also suffering from bipolar disorder is harmful. The diagnostic process can be tricky, however, especially for autistic people who find it hard to communicate with clinicians or have trouble adequaly relaying their emotional experiences.