Differentiating unipolar and bipolar depression

I don’t always trust the way the government uses its funds to research on health.

If you ask me why all that negativity, I turn to you: Do these  studies look like good ways of using around a couple hundred thousand dollars of government money to you?

Consider the National Institute of Mental Health’s study, “Octodon degus: A Diurnal, Social, and Long-lived Rodent.”  The goal was to see if the degu, a South American, well, rodent, mainly active during the day [hence diurnal,I suppose], could help us better understand jet lag.  I was a bit put off by this part of the author’s conclusion (and did question the use of the word “urgent” in this context):

“Additional studies of the interactive effect of photic and nonphotic signals on the function of the circadian system at the behavioral, anatomical, and cellular levels of analysis are urgently needed as we attempt to discern how to control circadian disorders in humans.”

Money well-spent.

And the NIMH, a subgroup of the National Institute of Health (NIH), is a mere amateur in comparison to its boss.

My personal favorite is their grant for measuring nicotine levels in toenails, which of course every smoker needs to do, at least once a month.   You’ll be happy to know that “[t]oenails were collected in 1982 from 62,641 [participating] women.”

I don’t have a price tag for this gem.

I do know, however, that the University of Kentucky received a $181,406 grant in 2010 from the NIH–to study how cocaine enhances the sex drive of Japanese quail.

Totally for real.

And, in 2011,  the NIH extended funding, giving an additional $175,587.

Not to be outdone, in “Promoting effect of massage on quadriceps femoris repair of rabbit in vivo, researchers used their grant money to investigate–not just massage in rabbits, as I would have imagined–but rather the “effect of massage on quadriceps femoris repair and the expressions of Desmin and alpha-Actin in rabbits.” Thank you for the specifics.

But, even our government, which is here to help us, sometimes does so.  And this time the NIMH (under auspices of the NIH) hit it spot-on, in a study that is both elegant and extremely important.

If you’re a frequent visitor to these pages, you might remember a post entitled “What does it take to be bipolar around here?” If you never heard of it, never read it, or are sure you might have read it but can’t remember the first thing about it, the important point is that people with bipolar disorder (BD) are so regularly misdiagnosed that in one major American study of over 4000 people with BD, over one-third of the subjects waited more than 10 years to receive a proper diagnosis.  And in a study done in 2012 in the UK and Scotland, the average delay was 13 years.

The delay is not only damaging–it can also be deadly. Lack of proper treatment leads to more episodes, which in turn leads to decreased functioning  Misdiagnosis as major depressive disorder leads to use of antidepressants, which often precipitate a manic attack. Additionally, knowing that those with BD commit suicide at 20 times the rate of the general population, there really isn’t time to play around.

Welcome the NIH, minus massaged rabbits and toenails with nicotine.

Even the numbers are elegant: For this study, researchers analyzed 54 women: 18 with bipolar I disorder (which involves more severe periods of mood episodes, ranging from mania to depression), 18 with what we just call ‘depression,’ but to differentiate it from bipolar depression is either referred to as ‘unipolar depression’ or ‘major depressive disorder,’ and 18 healthy women as the control group.

Now, I’m warning you here–this involves brain research, and publications on the brain are some of the most technical writings I’ve come across (and I actually tried taking a course in ancient Greek once in college).

Let’s start off  with the title: “Pattern recognition analysis of anterior cingulate cortex blood flow to classify depression polarity.” You can sense things going downhill right away, right?


And when they tell you what they did in their study, things don’t become all that much clearer: “we applied pattern recognition analysis using subdivisions of anterior cingulate cortex (ACC) blood flow at rest, measured with arterial spin labelling” [forgive that spelling–it’s a British paper, from the British Journal of Psychiatry. My spell-check is throwing fits.].

So far we can tell that for brain imaging they used an up-and-coming method called Arterial Spin Labelling. Apparently, no one has informed Wikipedia that this is all the trend in brain imaging, so on this topic it is uncharacteristically silent, leaving me, not to my own devices, but to solely scientific sites.

One promised a clear explanation, and I share it with you so you’ll have some sympathy with what I go through here on this blog, trying to make sense of gibberish time after time.  So this ‘clear’ site went on to explicate that “[i]n ASL, arterial blood water is magnetically labeled then imaged. First, arterial blood water is magnetically labeled just below the region (slice) of interest by applying a 180 degree radiofrequency (RF) inversion pulse. The result of this pulse is inversion of the net magnetization of the blood water. In other words, the water molecules within the arterial blood are labeled magnetically. After a period of time (called the transit time), this ‘paramagnetic tracer’ flows into slice of interest where it exchanges with tissue water. The inflowing inverted spins within the blood water alter total tissue magnetization, reducing it and, consequently, the MR signal & image intensity. During this time, an image is taken (called the tag image).”

I didn’t want to leave you dangling, and I’m glad we’ve taken care of that.

[Note to those I’ve lost: You can tune back in now.]

Look, in short, this thing measures blood flow in the brain–to regions that are correlated with depression, and–and I’m all about this; I don’t ever want an experiment done on me that involves invasive brain imagery–it does so in a non-invasive fashion.

The real point here (I know–you were wondering if I had one) is that this technique was able to identify with 81% accuracy which women had unipolar depression and which had bipolar depression.

Actually putting this to use, and thus accurately diagnosing BD earlier, can make, in lead author Jorge Almeida’s, MD, PhD, assistant professor of psychiatry at the University of Pittsburgh, words, “an enormous difference for patients and their families, and may even save lives.”

How soon can we expect this technique to be used as a clinical diagnostic tool? The principal investigator, Mary L. Phillips, MRCPsych, MD, said that was the “ultimate goal.” “It’s early days, but we’re hopeful that in 2 to 5 years, these neuroimaging biomarkers will get into clinical practice.”

Those with bipolar won’t have to wait 10, 13 years for a diagnosis. A quick brain scan–and their correct spot in the DSM is secured.  And you know who they’ll have to thank?


None other than the government funders of scientific research. You can thank them for this at the same time as write your appreciation for their funding of a study on visual perception in pigeons, linked here, for those who have always wanted to know about that self-same thing: “Pigeons’ discrimination of paintings by Monet and Picasso.” Enjoy.


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