The natural history of bipolar disorder (BD) is that it presents with depression, so the initial episodes are invariably diagnosed as major depressive disorder (MDD). However, once manic symptoms are evident, the diagnosis is “converted” to BD. This means that there is often a delay in accurately diagnosing TB, and any significant delay has an impact on the initiation of appropriate treatment. In some cases, treating MDD with antidepressants may contribute to the development of BD symptoms.
Previous research has shown that the median time from MDD diagnosis to BD is just under 10 years meaning that optimal treatment is often not prescribed for almost a decade. Therefore, it is imperative to have an idea not only of what predicts conversion, but also what affects the delay of a diagnosis from MDD to BD.
Resistance to antidepressant treatment is one of the most common predictors of diagnostic conversion from MDD to BD, and Bukh and colleagues reported a more than twofold increase in the rate of diagnostic conversion to BD after failure to respond to two initial antidepressant treatments. . Another common risk factor for diagnosis modification from MDD to BD is early onset of depression. Dudek and colleagues reported that patients with onset of depression before age 30 had rates of conversion to BD more than twice as high as patients with later onset.
Finally, conversion to BD has been found to be related to a family history of affective disorders, but this has not been a consistent finding. These studies suggest that patients who have been diagnosed with MDD are more likely to be subsequently diagnosed with BD if they had early onset of depression, do not respond to antidepressant treatment, and have a family history of affective disorders .
Although these studies help identify a future TB diagnosis after an MDD diagnosis, they only address disease characteristics and have overlooked other possible influences, such as psychological factors and patient characteristics.
Beyond predicting diagnostic conversion from MDD to BD, a relatively unexplored area is the lag period (i.e., the time interval between MDD diagnosis and BD diagnosis).
To date, the only variable that has been examined is the age of onset of depression. Dudek et al. found a negative correlation between the age of onset of the disease and the time of diagnostic conversion, that is, the lower the age of onset, the greater the delay. Therefore, the present study examined the time required to make a diagnosis of TB following an initial diagnosis of MDD, to better understand patient characteristics and psychological factors that may explain this delay.
| Aim |
A diagnosis of bipolar disorder (BD) is often preceded by an initial diagnosis of depression , creating a delay in accurate diagnosis and treatment of BD. Although previous research has focused on predictors of a diagnostic change from depression to TB, research on this delay in diagnosis is scarce.
Therefore, the present study examined the time required to make a diagnosis of BD following an initial diagnosis of major depressive disorder to better understand patient characteristics and psychological factors that may explain this delay.
| Method |
A total of 382 patients were clinically evaluated by a psychiatrist and completed a series of questionnaires.
| Results |
Ninety patients were initially diagnosed with depression with a subsequent diagnosis of TB, with a mean delay in diagnostic conversion of 8.74 years .
These patients who were later diagnosed with BD were, on average, diagnosed with depression at a younger age, experienced more manic symptoms, and had a more open personality style and better coping skills.
Cox regressions showed that depressed patients with diagnoses that ultimately converted to BD had been diagnosed with depression before and that this was related to a longer delay in conversion and a higher likelihood of dysfunctional attitudes.
| Conclusion |
The findings of the present study suggested that an earlier diagnosis of depression is related to experiencing a longer delay in conversion to BD. The clinical implications of this are briefly discussed, with a view to reducing the seemingly inevitable delay in the diagnosis of BD.
| Discussion |
Nearly a quarter of our patients (23.5%) who were initially diagnosed with MDD had their diagnosis changed to BD, supporting previous work indicating that a high percentage of patients who were initially diagnosed with MDD are ultimately rediagnosed ( converted ) to BD.
Although some authors maintain that almost half of TB patients (40%) are not correctly diagnosed at the time of initial presentation, our study found a lower percentage, probably due to the nature of the sample, which comprised a sample of outpatients presenting primarily for tertiary consultation, perhaps indicating a greater degree of complexity in pathogenesis and response to treatment.
The present study suggested that patients whose diagnosis was recalibrated to BD differed from those who remained with a diagnosis of MDD in age of initial mood disorder diagnosis, number of manic symptoms experienced, sensitivity to anxiety, Coping skills and openness of personality.
Patients whose diagnosis was converted to TB were diagnosed with depression at a younger age, according to key results from the Zurich study and the Polish TRES-DEP study. Furthermore, the Polish DEP-BI study found that a depressive episode before the age of 25 nearly triples the likelihood of a subsequent BD diagnosis. Although an earlier onset and diagnosis of depression is likely driven by biology, it does not equate to a more rapid conversion to BD, suggesting that other factors are likely at play.
The Polish TRESDEP study found that higher scores on the Hypomania Checklist-32 and the MDQ were associated with an earlier onset of depressive episodes and a diagnosis of TB. The latter was corroborated by the findings of our study. Patients in the present study experienced more manic symptoms, which may have increased the likelihood of detection and subsequent conversion to a BD diagnosis.
These patients also suffered more anxiety symptoms, which likely further complicated their presentation, making it more difficult to confirm the correct diagnosis. However, anxiety is also likely to prompt a person to seek help, which could increase the patient’s chances of getting an earlier diagnosis.
The results showed that these patients also have a more open personality style and better coping skills, protective factors that may lead them to be more likely to seek help, be more accepting of their illness, and have a better chance of coping – two variables that do not have been previously explored.
Therefore, patients whose diagnosis has been revised to TB are not only diagnosed with depression at a younger age and experience more manic symptoms and anxiety sensitivity, but also possess resilience factors , such as an open personality style and better coping skills, two psychological variables that are beneficial in patients with mental illness and potentially help delay the onset and therefore the diagnosis of BD.
The primary objective of the present study was to examine how patient characteristics and psychological factors affect delay in the recognition and diagnosis of TB in patients who have been previously diagnosed with MDD. It showed that, in patients whose diagnosis is eventually changed to BD, an earlier diagnosis of MDD is associated with a longer conversion delay than an initial diagnosis of MDD later in life.
This could be the result of numerous factors, such as a delay in psychiatric care following the initial diagnosis and treatment plan, a change in psychiatrist, or a possible decrease in the severity of symptoms and therefore lack of care. of follow up. Therefore, the delay for each patient may be longer than necessary.
As previous research suggests, it takes approximately 3 or 4 incorrect clinical assessments before a TB diagnosis is established and all of this may be delayed because younger patients are less likely to seek help when they are "feeling high energy" with symptoms (hypo )manic or there is insufficient awareness of the pathological nature of these symptoms.
The longer time to diagnosis for younger patients diagnosed with MDD may also be a result of fear associated with the stigma of mental illness, a concern more pronounced for men leading to a stronger association between an age of onset earlier and the delay in the conversion of the disease in men. However, this longer delay in younger patients may also simply be because they are younger and have more years ahead of them.
Nearly one-third of the patients in the present study were not diagnosed with BD until more than 10 years after their initial MDD diagnosis. Early recognition and initiation of effective treatment for TB is likely to reduce disability and improve outcomes.
| Conclusions |
Delay in the diagnosis of TB may be caused by: (i) an inherent inability to define TB ( taxonomic delay ) before the occurrence of a manic episode, even if the patient has had numerous depressive episodes; or (ii) a delay in identification ( detection delay ), in which the patient experiences hypomanic symptoms but does not seek help, or the doctor fails to detect the symptoms.
The present study, by focusing on associations with delay in diagnosis, revealed potential clinical markers for early detection of BD in patients who have not yet experienced or announced a manic episode. Research like this may help reduce the seemingly inevitable delay in diagnosing BD.
