Mistaking Depression for Bipolar Disorder: It’s Not Like The Movies

Like most psychiatric and mental disorders, the common misconceptions surrounding Bipolar Disorder greatly exaggerate real-life clinical presentations that may exist in day-to-day life. The association of Bipolar Disorder with psychotic, explosive, and manic episodes that seemingly come out of nowhere often dramatize the condition for entertainment and only truly represents the extreme-end of the spectrum. As such, the mild, moderate, and bipolar-adjacent conditions are cursorily overlooked by the public eye, leading to misattributions or misdiagnoses of similar or related conditions. Furthermore, treatment options for the incorrect condition may actually worsen the symptoms of Bipolar Disorder, further decreasing quality of life and normal functionality. This article hopes to clarify the misunderstandings with Bipolar Disorder and provide clarifying education surrounding mental health. [1]

What is Bipolar Disorder?

Bipolar Disorder (BD), also known as Bipolar Affective Disorder, is clinically defined as swinging between episodes of emotional “ups” and emotional “downs” from an emotional baseline, oftentimes in a cyclic or phasic nature. The “ups” are defined as an elevated or irritable mood or episode, and can be categorized as either manic or hypomanic. While both are described as hyperactive, mania is significantly more severe than hypomania, and could be potentially mistaken for other hyperactive conditions such as psychosis or schizophrenia. The “downs” are defined as a decreased and depressive mood or episode, and share many similarities with depression. Treatments typically consist of mood stabilization drugs paired with therapy to reduce the intensity of the “ups” and “downs”. However, when left untreated, these mood swings may severely and significantly impact social, occupational, or general function and cause significant distress over the course of a lifetime. As such, specific diagnostic criteria are required to distinctively identify BD. [1][2][3]

The differing severities of mood swings in Bipolar I Disorder, Bipolar II Disorder, and Major Depressive Disorder

The Different Types of Bipolar Disorder

Like most psychiatric conditions, a significant source of BD results from abnormal or nonfunctional regulation of neurotransmitters in the brain. Without proper regulation, moods can fluctuate and wildly swing up and down. Alongside mood and emotional regulation, these neurotransmitters also control sleep, appetite, alertness, sexual function, endocrine function. Therefore, people with BD symptoms tend to also experience unstable sleep, unusual appetite, and so forth. Symptom and disease management is attainable by pairing drug intervention to stabilize mood and therapy to prevent future mood exacerbations and to develop healthy coping mechanisms to avoid medication dependence. [1][2][3]

Listed below are the different subcategories within Bipolar Disorder:

• Bipolar I

• Bipolar II

• Cyclothymic disorder

• Specified bipolar and related disorders

• Unspecified bipolar and related disorders

While knowing the exact neurotransmitter profile is useful for designing drugs for treatment, it is not needed for diagnosing at the doctor’s office. The source of BD symptoms do not matter, whether from genetic, environmental, or acquired causes—only the presence or absence of those symptoms. Clinically, diagnostic criteria for BD and its subsets only involve identifying the presence of designated symptoms. Additionally, different diagnoses of BD have different diagnostic criteria regarding the type and severity of symptoms. [1][2][3]

Bipolar I Disorder and Manic Episodes

Bipolar I Disorder (BD-I) is what most people imagine when describing BD, and is characterized by the presence and severity of manic episodes; as such, the diagnostic criteria primarily revolves around the identification of manic episodes. Mania is clinically defined as a period of increased energy and either elevated or irritable mood that either persists for at least 7 days or results in hospitalization. Depending on presentation, 3-4 of the criteria below must be met to qualify for a manic episode and subsequent Bipolar I Disorder diagnosis:

• Inflated self-esteem or grandiosity

• Decreased need for sleep

• A compulsion to talk more than usual

• Racing thoughts or ideas

• High distractibility

• Increased goal-directed activity (socially, at work or school, or sexually) or non-goal-directed activity (psychomotor agitation)

• Excessive involvement in high-risk or hyperactive activities, such as social, physical, financial, or sexual recklessness

Manic episodes are markedly more severe than hypomanic episodes and must not be attributed to physiological sources of unrelated medications or substances. The manic episode may be preceded or followed by a hypomanic or depressive episode, but neither are required for diagnosis. These hyperbolic moods may be accompanied by delusions of grandeur, delusions of guilt, hallucinations, or other characteristic symptoms of psychosis. [1][2][3]

Bipolar II, Hypomanic Episodes, and Depressive Episodes

Bipolar II Disorder (BD-II) is less commonly known and more characterized by its depressive nature compared to BD-I’s manic nature. The diagnostic criteria for BD-II requires the identification of both a hypomanic episode and a depressive episode without a manic episode. Unlike BD-I, where manic episodes are required and depressive episodes are optional, BP-II requires the presence of both depressive and hypomanic episodes, and must not include manic episodes. 

The diagnostic criteria for a depressive episode requires meeting 5 of the criteria outlined below over a 2-week period:

• Depressed mood (either self-reported or observed by others)

• Anhedonia (inability to experience joy or pleasure)

• Unintentional significant weight loss or gain, or changes to appetite

• Changes in sleep (insomnia or hypersomnia)

• Uptick in non-goal-directed activities, or cessation of all activities

• Fatigue or loss of energy

• Feelings of excessive or inappropriate guilt, or of worthlessness

• Indecisiveness or decreased concentration

• Recurrent thoughts of death, recurrent suicidal ideation without a specific plan

The clinical definition and diagnostic criteria for a hypomanic episode are identical to manic episodes, only differentiated by its decreased severity or intensity—hence the term hypomania, meaning “under” mania or “not quite” mania. Only after identifying instances of hypomanic and depressive episodes can someone be diagnosed with BP-II. Additionally, those with hypomania do not experience psychosis during the mood extremities. [1][2][3][4][5]

Sub-Clinical Bipolar Disorders and related disorders

Milder BD-II symptoms may not meet the strict BD-II diagnostic criteria for hypomanic or depressive episodes, but still cause significant distress and require medical or therapeutic intervention. As such, other diagnoses describe the milder symptom presentation. [1][2]

For some, in the cyclic nature of BP-II, only a certain percentage of hypomanic or depressive episodes meet the BD-II criteria, while the remainder fall just short. If more than 50% of the hypomanic or depressive episodes fall short of the official diagnostic criteria for BD over the course of 2 years, it instead is diagnosed with Cyclothymic disorder. [1][2]

In other cases, the cyclic hypomanic and depressive episodes may fall short due to insufficient duration or severity: episodes may be too short, or the hypomanic episodes may never fully manifest alongside a manifested depressive episodes. Specified bipolar and related diseases describe these consistent sub-clinical hypomanic and depressive episodes. In the uncommon event that symptoms cause significant distress and impair social and occupational function but all fail to meet the aforementioned criteria, they fall under Unspecified bipolar and related diseases. [1][2]

Differentiation and Comorbidities of Bipolar Disorder with Other Psychiatric Disorders

While the scope of this article focuses specifically on differentiating between similar diagnoses, such as depression and bipolar disorder, only licensed professionals have the knowledge and wherewithal to properly identify, differentiate, and diagnose. Of course, it is also possible to be diagnosed with multiple psychiatric conditions–the official term being “comorbidity”–with their interactions and complications further necessitating licensed and professional guidance and monitoring. The following sections categorize brief overviews of either the differentiating factors, clinical similarities, comorbidity interactions, or treatment strategies for different comorbid psychiatric disorders with BD. [1][2][3]

Major Depressive Disorder vs. Bipolar Disorder

Many instances of Bipolar Disorder—namely BD-II—are misdiagnosed as "Unipolar" Major Depressive Disorder (MDD) due to its identical diagnostic criteria to the depressive episodes present in BD. However, one key difference is the constant persistence of the depressed mood in MDD contrasting the episodic and cyclic depressive and hypomanic episodes in BD-II. Because of hypomania’s mild-to-moderate nature compared to mania, the presence of hypomanic episodes are often missed or overshadowed by the more prominent primary focus on depressive episodes. As such, providers may also overlook potential hypomanic or manic episodes and instead focus on the depressive episodes—and subsequent BP-II diagnosis—to potentially diagnose MDD instead. [1][2][3][4][5][6]

Despite their clinical and diagnostic similarity, MDD and BD-II arise from different neurological and molecular etiologies. While not fully understood, many studies show differing brain activity, cell signaling, and blood testing in between those with MDD and BD-II—in other words, the root cause of each disorder is intrinsically different from each other, even though they may look similar on the surface. Therefore, medications for MDD such as antidepressants will not work for treating BD-II more often than not. As such, one major indication for adjusting a diagnosis from MDD to BD-II is an unreponsiveness or exacerbation of manic or hypomanic episodes when taking antidepressants instead of the expected improvement. [1][2][3][4][5][6]

However, it is important to note that MDD and BD-II are not mutually exclusive, and can sometimes coexist. Comorbidity of MDD and BD-II can further complicate symptom presentation and their effects due to its interactions. Especially in adolescents, they can increase the severity of depressive episodes or lessen the presentation of hypomanic episodes, and may increase the risk of substance abuse and suicide. Pairing therapy with medications for treatment proves especially helpful in comorbid cases of MDD and BD. [1][2][3][4][5][6]

Generalized Anxiety Disorder vs. Bipolar Disorder

The clinical definition of Generalized Anxiety Disorder (GAD; anxiety) presents as a persistent, excessive and unrealistic worry about everyday things, and can cause fear, worry, and a constant overwhelming feeling. GAD is difficult to control and often manifests with significant physical symptoms and can disrupt daily any otherwise normal function such as constant restlessness, fatigue, sleep disturbance, and irritability for at least 6 months. Historically, GAD was grouped in with other anxious, obsessive, or compulsive disorders as “neurosis”, which has since updated and expanded to more accurately reflect each disorder. [1][2][3][7][8]

While easily distinguishable, the comorbid presence of anxiety in Bipolar Disorder tends to markedly exacerbates the manic, hypomanic, or depressive episodes in BD to further destabilize mood. BD symptoms are often intensified, prolonged for longer periods of time, and take more effort to correct, requiring more intensive treatment. Without proper treatment, people with both BD and GAD commonly turn to unhealthy coping mechanisms such as substance abuse and are at higher risk for suicide. [1][2][3][7][8]

Treating both disorders is essential to improving quality of life and normal cognitive function. Considering the negative feedback loop of anxiety and BD, the general principles of treatment prioritize stabilizing mood through medications before engaging in therapy to help develop healthier coping mechanisms through therapy. [1][2][3][7][8]

Schizoaffective Disorder vs. Bipolar Disorder

One of the most common psychosis-inducing disorders is Schizoaffective Disorder (SAD), which is closely linked with Schizophrenia. The characteristic symptoms of Schizophrenia involve prolonged delusions, hallucinations, and disorganized speech (such as frequent derailment or incoherence) during a 1-month period. Symptoms may also include grossly disorganized or catatonic behavior or negative symptoms such as diminished emotional expression. SAD additionally requires the presence of manic or depressive episodes that Schizophrenia does not. [1][2][3][9][10]

While SAD and BD—namely BD-I—both share similarities with the inclusion of manic and depressive mood instability, they differ significantly in psychosis presentation. In BD-I, psychotic symptoms are only present during the manic or depressive episodes; psychotic symptoms must exist outside of those episodes for 2 weeks to be considered SAD. [1][2][3][9][10]

The distinctions between BD, SAD, and Schizophrenia are not clear within the scientific literature. It is widely accepted that BD, SAD, and Schizophrenia exist as a spectrum from mood instability to psychosis, with SAD existing in between BD and Schizophrenia in that spectrum. Treating SAD involves the mood stabilizing medications commonly used for BD and the antipsychotic medications commonly used for Schizophrenia, and their interconnectedness can complicate diagnosis and treatment. [1][2][3][9][10]

Borderline Personality Disorder vs. Bipolar Disorder

The remarkable characteristics of Borderline Personality Disorder (BPD) is instability in mood, self-perception, and relationships with others. The term “borderline” originates from its original description of those who are on the border of neurosis and psychosis. Both BD and BPD are associated with increased morbidity, elevated rates of suicide, and considerable functional impairment. Similarly to BD, BPD is mainly diagnosed based on descriptions of symptoms and criteria requirements, and does not account for the source of those symptoms. [1][2][3][11][12]

Personality disorders are widely characterized by a warped perception of reality; in Narcissistic personality disorder, that warped perception is of self-grandeur; in Paranoid personality disorder, the warped perception is the absence of trust and abundance of suspicion; in Obsessive-compulsive personality disorder, the warped perception is of orderliness and impulsion. With BPD, the warped sense of perception is in how they perceive themselves and their relationships with others. Symptoms often present as correlating neutral facial expressions with negative ones, viewing interactions as extremes or without nuance, and may even also include transient psychosis. Mood can often swing up and down drastically and can lead to manic or depressive episodes based on interactions with other people. [11][12][13]

Aside from the similar acronyms, many people confuse BD and BPD because of their seemingly unpredictable mood swings of mania or depression. Additionally no well-defined biological markers or physiological mechanisms are currently available to differentiate BD and BPD. The key source to differentiating currently is to observe interactions longitudinally to determine if the source of the mood instability is either dependent or independent from interactions with others. Differentiation and treatment becomes even more difficult when symptoms of both BD and BPD are comorbidly present, necessitating further research and investigation to improve diagnosis and treatment. [1][2][3][11][12][13]

Conclusions

Bipolar Disorder’s layperson association with psychosis fails to accurately represent the full spectrum of the disorder and mischaracterizes all cases as the most extreme example. Many symptoms, including depressive symptoms or its cyclic nature, often escape detection and misguide prognoses, diagnoses, and treatments. Additionally, the presence of additional psychiatric disorders further complicates symptom presentation and treatment management. However, under the careful guidance and management from doctors, Bipolar Disorder symptoms can be identified and managed to improve quality of life. 

References

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