Diagnostic Anchoring in Psychiatry: ADHD Misclassified as Bipolar II Disorder in a Treatment-Resistant Patient: a case report
This case report illustrates how diagnostic anchoring led to the long-term misclassification of an adult woman's ADHD as bipolar II disorder, resulting in treatment resistance until a systematic reassessment prompted a correct diagnosis and successful targeted pharmacotherapy.
Original paper licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). This is an AI-generated explanation of the paper below. It is not written or endorsed by the authors. For technical accuracy, refer to the original paper. Read full disclaimer
In the world of psychiatry, doctors often rely on the stories patients tell and the behaviors they show to understand what is wrong. Unlike a broken bone, which shows up clearly on an X-ray, the human mind does not always offer a single, objective test to confirm a diagnosis. Because of this, a common mental shortcut called "diagnostic anchoring" can take hold. This happens when a doctor forms an initial idea about a patient's condition and, perhaps without realizing it, holds onto that idea even when new information suggests it might be wrong. Once a label is attached, it can stick across many different doctors and years of treatment, sometimes leading to the wrong medications being prescribed while the real problem remains hidden. This is particularly tricky with attention-deficit/hyperactivity disorder, or ADHD, in adults. While many people think of ADHD as a condition of childhood hyperactivity, in adults—especially women—it often looks like trouble focusing, intense emotional swings, and a feeling of being overwhelmed. These symptoms can easily be mistaken for mood disorders, leading to a long and frustrating journey of ineffective treatments.
A recent case report by Lisa George brings this issue into sharp focus by telling the story of a woman in her late forties who had been struggling for decades. For most of her adult life, she had been diagnosed with bipolar II disorder, a condition characterized by periods of depression and milder highs called hypomania. This diagnosis was given to her in her mid-twenties after she experienced a period of unusual energy and grandiosity while taking an antidepressant. Over the next twenty years, she saw numerous doctors and tried more than fifteen different medications, including mood stabilizers and antipsychotics, yet she never found lasting relief. Her symptoms of depression, anxiety, and impulsive behavior persisted, and she remained unable to function well in her daily life. The medical team treating her at the time was working within the framework of bipolar disorder, assuming that if her current medications were not working, they simply needed to try a different combination of drugs for that same condition.
The turning point came when the treating physician decided to step back and question the original diagnosis itself, rather than just adjusting the medication list. The team looked closely at her history and realized that the "highs" she experienced had never happened on their own; they only occurred when she was taking antidepressants. Furthermore, she had no history of spontaneous mood episodes over two decades, which is a key requirement for a bipolar diagnosis. Instead, the doctors found a pattern of lifelong struggles that pointed elsewhere. They used specific interview tools and questionnaires designed to uncover attention deficits, which revealed that her impulsivity, inability to sit still, and emotional volatility were actually classic signs of ADHD that had been missed since childhood. The diagnosis was changed from bipolar disorder to ADHD, along with a separate diagnosis of depression.
Once the label changed, the treatment plan changed completely. The doctors stopped the heavy medications used for bipolar disorder, such as mood stabilizers and antipsychotics, and started her on a stimulant medication specifically for ADHD. The results were rapid and profound. Within just one week, the constant, racing thoughts that had plagued her for years quieted down. Within two weeks, her sleep improved, her ability to hold a job returned, and the compulsive behaviors she had struggled with vanished. By the two-month mark, her scores for depression and anxiety had dropped dramatically, moving from severe levels to mild ones. She described the experience as the fog lifting from her mind, allowing her to think clearly for the first time in decades. She noted that the maladaptive daydreaming she used to escape her thoughts had stopped, and she was no longer making impulsive decisions that ruined her life.
This case serves as a powerful reminder that when a patient does not respond to treatment, the diagnosis itself should be reconsidered. The author suggests that diagnostic anchoring can keep patients trapped in ineffective treatment cycles for years, particularly when symptoms of ADHD are mistaken for mood disorders. By carefully re-examining the history and using the right tools to look for attention deficits, the medical team was able to identify the true cause of the patient's suffering. The story illustrates that sometimes the most important step in healing is not adding a new drug, but having the courage to ask if the original understanding of the problem was correct.
Drowning in papers in your field?
Get daily digests of the most novel papers matching your research keywords — with technical summaries, in your language.