How is bipolar disorder diagnosed?

Currently, the diagnosis of bipolar disorder is based solely on clinical symptoms. We have not yet found imaging or blood biomarkers, for example, for bipolar disorder, although this is a research prospect for years to come.
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At what age does bipolar disorder begin?

A typical age of onset was said to be around 30-35, but this is actually the age of diagnosis. But there is a huge delay in diagnosis: it is not uncommon to see a 10-year delay between the first symptoms and diagnosis. The first symptoms are therefore much earlier than the diagnosis of the disorder, and usually begin in your twenties. Some forms begin in adolescence, sometimes with a different expression of symptoms. Others are diagnosed much later, at the age of 50 or 60, often with a resistant depressive episode.


Identification of manic or hypomanic phases

The heart of the diagnosis is the identification of manic or hypomanic phases. There are also so-called unipolar disorders, such as recurrent depressive disorder, in which there is a repetition of depressive episodes without a manic episode. Similarly, there is no unipolar disorder with manic phases, as there is with bipolar disorders.

The presence of a single manic or hypomanic episode is therefore sufficient to make the diagnosis, and to affirm a risk of a new manic or depressive episode.

However, while manic or hypomanic episodes are at the heart of the diagnosis, it is often the depressive episodes that are the most frequent and the longest in a person with bipolar disorder.

Historically, the focus has long been on the more visible and characteristic manic episodes of the disease, whereas the core of bipolar disorder is based on the dominance of depressive disorders, which are particularly unbearable for patients. When the disorder speaks for itself.

Sometimes the diagnosis of bipolar disorder is easily recognizable, and not subject to suspicion of other mental or psychiatric disorders.

This is particularly the case when the patient is initially treated for a manic or hypomanic episode.

Some patients will also consult and report seasonal fluctuations that affect their behaviour and psychological balance. There is even scientific evidence of a link between variations in exposure and mood. For example, a hypomanic episode every spring may outline bipolar spectrum disorder.

It is also common for patients to report that depressive episodes follow a hypomanic (sometimes very short) episode, much as if the episode in question had consumed the patient’s energy and the depressive episode had a corresponding effect.

Diagnosis of Bipolar Disorder: Current Steps

Most often, the patient comes in for depression, and it is a bundle of arguments that leads us to bipolar disorder.

When bipolar disorder is suspected, it is very important to involve others, such as family, friends or spouses. In fact, as often as not, patients are easily aware of their condition when they are depressed, there is often anosognosis, that is, an inability to become aware of the symptoms during a manic or hypomanic episode. Similarly, depressed patients often have great difficulty remembering their manic or hypomanic episodes.

In addition to looking for manic or hypomanic episodes, it is also important to look for a history of bipolar disorder in the family.

Indeed, there is a genetic component to this pathology. Death by suicide, which may be caused by an overly rapid and uncontrolled response, or by a lack of effectiveness of antidepressants in depressive episodes, is also a pathway to validation of diagnosis.

Finally, the characteristics of manic-depressive episodes can sometimes lead to a diagnosis, even if often without certainty.

The next step is differential diagnosis confirming, or not, bipolarity. That is, check for bias in this diagnosis, that the patient’s symptoms are not due to other factors.

Other factors that may prevent bipolar disorder include:

  • The use of narcotics such as cocaine, similar to hypomanic phases.
  • Neurological or hormonal pathologies, such as thyroid dysfunction, which may result in similar symptoms.

It should be noted that these are also often more co-morbidities than genuine alternatives to diagnosis.

For example, bipolar disorder is often associated with other psychiatric disorders such as anxiety disorders, attentional disorders with or without hyperactivity, or addictive disorders.

Bipolar disorder may also be associated with non-psychiatric disorders, which in turn may aggravate existing disorders. An example is obstructive sleep apnea syndrome.