Coming as a surprise to more than a few mental health professionals, a new study out today suggests that bipolar disorder is often missed in patients who present only with major depression. The study examined 5,635 adults seen at community and hospital psychiatry departments in a number of different countries.
The discrepancy was reported because of the use of “bipolarity specifier criteria” that are broader than the DSM-IV criteria, the standard for diagnosis of mental disorders by mental health professionals.
Using the broader bipolar criteria developed by the researchers found an additional 31 percent of patients who could have been diagnosed with bipolar disorder.
So what’s really going on here? Are professionals really “missing” bipolar disorder? Or have the researchers stacked the deck in this study simply to suggest it is so?
Here are the findings, according to the news article reporting on the study:
DSM-IV-TR criteria for bipolar disorder were met by 903 patients (16.0%; 95% confidence interval [CI], 15.1% – 17.0%), and bipolarity specifier criteria were met by 2647 patients (47.0%; 95% CI, 45.7% – 48.3%). When both sets of criteria were applied, there were significant associations with bipolarity for a family history of mania or hypomania and multiple past mood episodes. When only the bipolarity specifier was used, there were also significant associations for manic/hypomanic states during treatment with antidepressant drugs, current mixed mood symptoms, and comorbid substance use disorder.
The obvious question to me is, what the heck are these “bipolarity specifier criteria” mentioned by the researchers? Why haven’t most professionals ever heard of these criteria before?
These sub-threshold bipolar criteria were first proposed by Angst et al. in 2003 (coincidentally the lead researcher in the new study) and take the following form:
This bipolarity specifier attributes a diagnosis of bipolar disorder in patients who experienced an episode of elevated mood, an episode of irritable mood, or an episode of increased activity with at least 3 of the symptoms listed under Criterion B of the DSM-IV-TR associated with at least 1 of the 3 following consequences: (1) unequivocal and observable change in functioning uncharacteristic of the person’s usual behavior, (2) marked impairment in social or occupational functioning observable by others, or (3) requiring hospitalization or outpatient treatment. No minimum duration of symptoms was required and no exclusion criteria were applied.
In other words, the researchers have re-written the DSM bipolar disorder criteria to rope in people who wouldn’t ordinarily qualify for the diagnosis. They’ve set the threshold lower, making it a “sub-threshold” diagnosis.
One could argue that all of the criteria in the DSM are somewhat arbitrary. For instance, why do you need to meet five criteria for depression? Why not 4? Or 3? Sure, there’s data to suggest five is a good compromise in terms of ensuring you catch legitimate clinical depression in people, without roping in people who don’t actually have it.
But in this case, I have to wonder. A single case of irritable mood along with the very subjective observation of an “unequivocal and observable change in functioning uncharacteristic of the person’s usual behavior” hardly seems sufficient to qualify a person to be characterized as having “bipolar disorder.” It seems like you could classify significant portion of the population with these two characteristics combined.
So why would you want to propose a set of sub-threshold criteria for bipolar disorder that would, by their very design, include a lot more people? If professionals were to adopt these criteria, more people could ostensibly be diagnosed with bipolar disorder… and then need treatment.
What kind of treatment would they need? Why, bipolar medications, of course. And who makes a medication for bipolar disorder? The study’s primary sponsor — sanofi-aventis:
Financial Disclosure: All investigators recruited received fees, on a per patient basis, from sanofi-aventis in recognition of their participation in the study.
Role of the Sponsors: The sponsor of this study (sanofi-aventis) was involved in the study design, conduct, monitoring, data analysis, and preparation of the report. The study sponsor funded an independent contract research organization (SYLIA-STAT; Bourg-la-Reine, France) to collect and analyze the data and to generate the statistical report.
So sanofi-aventis designed the study, and was involved in every aspect of the study’s implementation, data collection and final analysis. Huh.
Certainly some people who present with major depression can be mis-diagnosied with depression when they actually have bipolar disorder. It does happen, since sometimes a clinician may not ask the right questions to determine the presence of an earlier bipolar episode. But it’s not such a problem as these researchers would suggest, missing an entire swath of 30 percent more people.
Needless to say, you can take this study’s findings with a big grain of salt.
Read the full article: Bipolar Disorder Underlying Major Depression May Be Missed