Why is Bipolar Disorder Overdiagnosed?
A 2007 study published by Moreno, et al. in the Archives of General Psychiatry
(https://www.ncbi.nlm.nih.gov/pubmed/17768268) found that, between 1994 and 2003, diagnosis of bipolar disorder in youth increased by about 40-fold. Diagnosis of bipolar disorder nearly doubled for adults during this same time-frame. In their conclusions, the authors summarized, “This increase highlights a need for clinical epidemiological reliability studies to determine the accuracy of clinical diagnoses of child and adolescent bipolar disorder in community practice.” This study’s results are fairly spectacular and unmatched by other similar studies I have reviewed. However, other more modest studies (https://www.ncbi.nlm.nih.gov/pubmed/17306773) also show remarkable increases in bipolar disorder diagnosis. For example, Blader & Carlson found “the rate in 1996 was 1.3 per 10,000 U.S. children and climbed to 7.3 per 10,000 U.S. children in 2004.” How could this be possible? There would be no rational explanation for why bipolar disorder would actually become more common over a mere 8 to 10 year period. While it is possible that some of this inflation was the result of previous under-diagnosis, the primary reason for this inflation is current over-diagnosis.
Based on my clinical experience, this is usually due to one or more of the following reasons:
Money: Clinicians can bill medical insurance for bipolar disorder. Some clinicians realize that a patient has borderline personality disorder or another diagnosis. However, many insurance companies will not reimburse for these diagnoses (or will heavily limit reimbursement). The companies will reimburse for bipolar disorder so the doctor gives a bipolar diagnosis instead.
Clinician Inexperience: The majority of patients seeking diagnosis of and treatment for bipolar disorder are first seen by general practitioners or family doctors. These clinicians generally do not have advanced training in mental health and often have a high volume of patients they must see daily. Many such physicians have completed a single months-long psychiatry rotation during medical school but have little training or experience beyond this. Even many mental health professionals genuinely do not know or understand the diagnostic criteria for bipolar disorder. Many clinicians hear “mood goes up and down,” immediately assume bipolar, and provide the diagnosis. Sadly many clinicians do not realize a manic episode must last at least a week in order to qualify (unless the severity requires hospitalization or emergency treatment). For some clinicians, diagnosis is essentially left to guess-work.
Insufficient Resources: Some mental health professionals feel rushed, burned out, or are limited in resources (e.g., one person may have an overwhelming case-load). As a result, they spend very little time considering the diagnosis or examining information supporting other more appropriate diagnoses. If they see another clinician provided a diagnosis of bipolar in the past or the patient says they “feel bipolar,” the clinician may assign the diagnosis and quickly move on to the next case. Errors arise when a diagnosis is given without enough time or thought.
Favored Diagnosis: Some diagnoses go in or out of style in certain settings. Diagnoses such as eating disorders, dissociative identity disorder, and borderline personality disorder have each seen rapid increases during short periods of time. Then many diagnoses (also such as dissociative identity disorder) will suddenly decrease in prevalence as it loses support from the mental health community. In addition to favored diagnoses within the culture, certain clinicians will tend to have certain diagnoses they prefer. One psychiatrist may have extensive training in PTSD treatment and may be more likely to identify and diagnosis this in response to a patient with a trauma history. Another psychiatrist who specializes in depression may diagnose major depressive disorder for this same patient because that is the lens through which he/she views the patient. Specialization and favoritism in one clinical area may blind clinicians to alternative hypotheses.
Diagnostic Overlap: A number of other diagnoses and presentations have symptoms and associated features which overlap with bipolar disorder. Generally, lay-people, physicians, and even mental health clinicians associate bipolar disorder with the manic symptoms of high energy and unstable mood. For many people (clinicians included), this is the full extent of their memorized knowledge of bipolar disorder diagnostic criteria. However, attention-deficit/hyperactivity disorder, schizoaffective disorder, intermittent-explosive disorder, and disruptive mood dysregulation disorder can be associated with high energy. Though disruptive mood dysregulation disorder and intermittent-explosive disorder will only have high energy in short bursts, they will also have simultaneous dysregulated mood which can confuse clinicians. I have seen many instances in which behavioral problems better categorized as oppositional defiant disorder or conduct disorder are diagnosed as bipolar disorder. The child/adolescent is very irritable, defiant, angry, violent, and aggressive. Because the patient’s mood fluctuates rapidly between anger and anything else, the clinician will think of bipolar disorder and provide the diagnosis without support for any additional diagnostic criteria. Borderline personality disorder may be one of the most frequent diagnoses confused with bipolar disorder. Borderline personality disorder is associated with instability in multiple areas of functioning (e.g., mood, interpersonal relationships, self-identity).
There is unlikely to be a simple or easy solution to the current diagnostic issues with bipolar disorder. However, if you feel you or a loved one has been misdiagnosed, the next step may be to ask for a second opinion, consultation, or a thorough examination. If this is something which interests you, ensure that you seek an assessment from a clinician with specialized training and experience who will perform a thorough and comprehensive evaluation.