Sometimes clients come into treatment with one diagnosis and leave with a different one. This can be confusing and frustrating for clients and their loved ones. Was the last doctor completely wrong? How is this possible?
If I arrive at a different diagnosis from another doctor, it doesn’t necessarily mean that one of us doesn’t know what we’re doing. More likely, it means that we’re working with different information and diagnostic criteria.
There is much that goes into making a mental health diagnosis. Conflicting information and incomplete client histories must be measured against the mental status examination (MSE), any empirical evidence we gather and the diagnostic criteria in our medical manuals.
Teasing out the truth involves a combined process of observation, deduction and analysis. It is critical for clients that we arrive at an accurate mental health diagnosis and apply the treatments most likely to benefit them. Yet and still, psychiatry, like other areas of medicine, is an imperfect science [practice] and we face several challenges when making a mental health diagnosis:
Challenge #1: Lack of Physical Evidence
We don’t have hard physical evidence to rely on when making a mental health diagnosis. While we often use the results from physical exams or lab tests to rule out medical conditions that may cause symptoms, no brain X-rays, blood work or genetic tests are available to aid us in reliably diagnosing mental health disorders with 100% accuracy.
What we have is the client’s history — their medical and family history, including a record of symptoms or behaviors over time. However, depending on their mental state, our client is not always the most reliable historian. The client may be psychologically impaired, or has been at some point in their life, due to the course of their mental illness or substance abuse. This means their memory may be fuzzy or their interpretation of symptoms and experiences is subjective and potentially inaccurate. For these reasons, we often rely on partners or family members for additional reports of the history.
Challenge #2: Time
Time also creates challenges. For example, it is sometimes easier to get accurate histories from older clients because they have had more time to gather a timeline of behaviors and recognize patterns over the years. There may have been periods during their histories when they were not taking any medications and they didn’t have certain behaviors, but things changed later when they started taking medications, with certain symptoms or behaviors getting better or worse.
Yet, even with older patients, the issues of subjective interpretation, context-dependent or state-dependent memory (memory retrieval that works best if an individual is in the same context and/or state of consciousness they were in when the memory was formed) pose challenges. These issues make it difficult to accurately map changes over time. Clients may look back on periods of time when their symptoms were more acute and report this was because their medication wasn’t working, when in fact they may have been experiencing a relapse.
Challenge #3: One Thing Can Look Like Another
Substance misuse can further complicate the diagnosis of a person’s condition. Alcohol and other drugs can cause symptoms that look like the symptoms of a mental health disorder and, in some cases, can even induce mental health symptoms. Other times, substances can mask symptoms of a disorder so that an underlying condition isn’t recognized or diagnosed until the client has undergone drug detox and rehabilitation, and is free of the substance’s effects.
For example, cocaine intoxication can look like, or induce, mania — and mania, a feature of bipolar disorder, can look like cocaine intoxication. The heavy use of cocaine or other stimulants like amphetamines can also produce symptoms that look like paranoid psychosis, a feature of schizophrenia. Yet, with cessation of the stimulant, the psychosis may disappear and the person experiences a post-stimulant crash, sinking into what appears to be depression. However, the depressive symptoms can be linked to amphetamine withdrawal and, as a result, may not meet all the criteria for a diagnosis of clinical depression.
Sorting out what is what, therefore, takes time and careful investigation. If an individual consults with a mental health professional when they are struggling with co-occurring disorders that have overlapping symptoms, this can lead to an inaccurate or incomplete diagnosis.
This is why many mental health professionals delay formulating a diagnosis until substances have been detoxed from a client’s system. After detox, working with the client for an extended period allows us to observe symptoms and changes, plotting what happens over time to better formulate a theory of an illness. During this time, the mental health professional may consult with family members to get a more comprehensive picture of the client’s symptoms over time.
Challenge #4: Changing Histories and Diagnostic Criteria
The phenomenon of different doctors giving the same client different diagnoses can occur if they are relying on different parts of a person’s history to make a diagnosis. Gaps in the history means that crucial diagnostic evidence is missing. To guard against such problems, it helps to gather a client’s early history, particularly if the client has been abusing substances.
To gather a pre-substance history, a client’s family members can be great resources if they are available. For example, a parent can be a resource. Did they observe certain behaviors when the client was a child, before substances entered the picture?
Sometimes I have received surprising clues from parents that indicate a mental health disorder may have been present, but undiagnosed, in childhood — long before the client presented with more noticeable symptoms or started self-medicating with alcohol or other substances. For example, the mother of one client I was seeing for possible bipolar disorder reported that when her boy was 8 years old, he pilfered checks from her checkbook and used them to mail-order expensive train sets and other toys. This behavior was not typical for an 8-year-old, and looked very much like an early manifestation of the compulsive spending that is a hallmark feature of bipolar disorder. It is helpful, then, to examine the history of childhood behaviors and compare them to the current behaviors observed in the client.
Parents or other family members also can serve as resources on family genetics. They may know of related conditions that manifested in grandparents or other relatives, and this information can give us insights into inherited conditions. For example, unipolar depression in a relative can be inherited by the next generation as bipolar disorder, due to variability in the genes.
Even genetics are not absolute, however. We must cross-reference hereditary conditions against other components of a client’s history, and also in the context of any empirical evidence we gather (usually through observation), and compare these to diagnostic criteria listed in the current edition of the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders for a particular disorder. Only after considering all the factors are we able to make a diagnosis and proceed with a treatment plan to help each individual.
Challenge #5: One Treatment Can Work for More Than One Disorder
An unfortunate outcome of differing diagnoses can be differing treatments, which can further muddy the waters. A treatment for one mental health condition often helps another, so an individual who has co-occurring conditions might only be diagnosed with one, but the single treatment they receive has dual benefits. Does this mean they only have the one illness? Not necessarily.
Diagnoses are not mutually exclusive, so it would be a fallacy to assume that if the medication designed to treat X illness works for this patient, then this patient’s diagnosis must be X illness. In other words, one diagnosis can obscure another. If there are co-occurring illnesses that have not been fully explored, this can lead to heartbreak for the client and their family down the road when they receive a “new” diagnosis. It may be that the second condition was, in fact, present all along but flying under the radar until a visit to rehab or a change in medications, hormones or circumstances revealed a different set of symptoms or criteria that allowed the second diagnosis to be recognized and treated.
Making the correct diagnosis requires thorough detective work that leaves no stone unturned — something that is not always possible with every client all the time. Arriving at a treatment that helps the client feel better as soon as possible is our ultimate goal. Sometimes, getting there means we have to work from an “early diagnosis” until we can extend our investigation further and gather more information to make a more accurate diagnosis.