Quantifying the Consequences of Misdiagnosing Bipolar I Disorder

In an interview with Veteran's Health Today, Roger McIntyre, MD, FRCPC, professor of psychiatry and pharmacology, University of Toronto, and head, Mood Disorders Psychopharmacology Unit, University Health Network, Toronto, shares how real-world data reveals the gravity of misdiagnosing bipolar I disorder.

Could you share a brief overview of the findings from your study on the real-world health care resource utilization and costs of misdiagnosing bipolar I disorder?

We know that many people who are living with bipolar disorder or depression are not accurately diagnosed, or they are not diagnosed in a timely fashion. Therein is the reason why we need to identify a tactic to diagnose patients faster and more accurately. Issues with diagnosis negatively affect the patient's own experience of their illness, but also has implications for appropriate treatment selection and cost-effectiveness.

Our report indicated that accurate, timely assessment and diagnosis have significant implications from a cost perspective for patients living with mood disorders and for society at large. 

Why is bipolar I disorder commonly misdiagnosed as major depressive disorder?

There are several reasons why bipolar disorder is misdiagnosed.

First, for many people with bipolar disorder, despite the fact mania and hypomania define the condition, depression is the predominant presentation of the illness. Depression is also the presentation that most likely causes patients to visit a health care provider. Bipolar disorder will most often present in clinical practice as depression. Consequently, the diagnosis of bipolar disorder by clinicians is either not contemplated or is superficially considered. 

Second, bipolar disorder is often misidentified because of the complexity of the diagnosis. When patients typically present with depression, often they are not aware of or have forgotten experiencing a prior episode of hypomania or mania. 

Third, when many people with bipolar disorder first become ill, depression is the most predominant initial presentation. Since there has yet to be any declaration of hypomania or mania, the only identifiable symptom is depression. The clinician, the patient, and others would not be aware that a patient could ultimately declare bipolarity. 

What lengths can be taken to help prevent misdiagnosing bipolar I?

It is critical that all practitioners contemplate the possible diagnoses of bipolar disorder in any patients presenting with depressive symptoms. This should be the case for anyone who is presenting with depression at the initial consultation or a follow-up appointment. Practitioners should also consider revisiting a diagnosis when a patient is being prescribed treatments for their depression that have not been sufficient in alleviating their depressive symptoms. 

Could you discuss the significance of these misdiagnoses from a resource and cost perspective? 

When a patient has been misdiagnosed, typically, they are placed on treatments that are less helpful and potentially harmful. This means the illness continues to be active and unmanaged; and as a consequence of that, patients are much more likely to utilize health care services and require treatments. 

When patients with bipolar disorder are not diagnosed accurately or quickly, they continue to experience manifestations of the illness and may not be able to perform as a homemaker, employee, volunteer, and so on. Thus, a human capital cost is associated with prolonged, untreated illness. The overall impact of an inaccurate or poorly defined diagnosis is that both direct and indirect health care costs are increased, as well as larger societal costs. 

Bipolar disorder is a severe, lifelong, debilitating, and very costly disorder. The positive, however, is that this is modifiable. With more timely and accurate diagnoses, we should be able to reduce these associated costs and utilization. 

Is there anything else you would like to share? 

I think it is important to separate treating bipolar disorder into 2 parts. The first part is to diagnose the illness correctly, quickly, and accurately. The second part is to follow up and ensure patients receive appropriate treatment for bipolar disorder. These improvements can reduce our overall costs and health care resource use.

About Dr McIntyre
Roger McIntyre, MD, FRCPC, is a psychiatrist and professor of psychiatry and pharmacology at the University of Toronto. He is also head of the Mood Disorders Psychopharmacology Unit at the University Health Network, Toronto. His clinical and academic interests have been focused on providing care for people with mood disorders, major depression, and bipolar disorder.