Many illnesses can be diagnosed by simply going to the doctor and getting a blood test. Based on the latest research, adults could soon be getting a blood test to determine whether they have depression. This blood test would effectively assess the severity of depression, how well a person would respond to certain medications, and whether they are likely to get any benefit out of therapy sessions.
Current diagnoses for depression involve a series of questions and self-reports. It is usually difficult to judge the accuracy of these self-reports for the doctor. Additionally it leaves room for diagnostic misinterpretations from the doctor and over or under-reporting of depressive symptoms from the patient.
Although diagnosing depression is considered somewhat accurate, much of the process is based on subjective interpretations of symptoms. Should an actual blood test get approval to diagnose depression, a doctor wouldn’t have to worry as much about correct interpretation of symptomatology.
Blood Test for Depression: How The Process Works
It’s not very difficult to determine how doctors take a blood sample. It may be a little more confusing to understand how a sample can be used to determine whether you really have major depression. Essentially lab workers will analyze the blood sample and check for specific RNA markers that signal depression or non-depression. RNA works based on programming from our DNA. Whatever our DNA is signaling, our RNA carries out – this is expressed in our physiology.
- Blood sample is taken: You would obviously need to get blood drawn from your arm and a sample would be collected.
- Blood sample analyzed: The sample would then be analyzed to determine whether it has specific RNA markers that would represent depression.
- RNA Markers: Researchers are able to identify specific RNA markers in a person’s blood stream in those with depression vs. those without. Those who have depression tend to have significant differences in RNA markers when compared with healthy individuals.
- Results: The results from the blood sample would then indicate to a lab worker whether you are depressed, not depressed, and whether you have a predisposition to developing depression.
- Depression: If you have depression, it would be evident based on your sample.
- No depression: If you are healthy and don’t have depression, your RNA would be significantly different than someone who is depressed.
- Predisposition: Some people that weren’t depressed can be identified as having a higher overall risk for developing depression. This demonstrates that RNA markers within the bloodstream can indicate whether someone could be at risk for eventually developing depression.
Research from Northwestern University (2014): Depression Blood Test
Researchers from Northwestern University Feinberg School of Medicine have come up with the first blood test to diagnose depression in adults. They did this by measuring 9 specific RNA blood marker levels. RNA molecules are able to carry out DNA expression. This suggests that those who are depressed have DNA signaling to the RNA to express this emotion.
In addition to the blood test being able to determine whether a person was depressed, it also demonstrated reliability in determining patients that would be good candidates for CBT (Cognitive Behavioral Therapy) and who wouldn’t based on the RNA markers. It is thought that this will eventually lead to more personalized treatments for adults with major depression.
In line with predicting which individuals would respond well to CBT, it also was able to detect changes after a person went through extensive CBT. Those who had gone to therapy for an 18-week period and were less depressed also showed less depression based on RNA levels and behavior. Lead researcher Eva Redei stated that this study shows “that you can have a blood-based laboratory test for depression.”
She suggested that this blood-test would be similar to the way someone is “diagnosed with high blood pressure or high cholesterol.” In the past, Eva Redei had come up with a blood test protocol for diagnosing depression among adolescents, but the markers for adolescent depression were different from those expressed in adults.
The study was able to distinguish whether CBT, a medication, or a combination of both options would be beneficial; this will help optimize and individualize treatments. Using current treatments are essentially a “shot in the dark” or referred to as “scattershot approach.” Simply put, a blood test for adults with major depression could have significant implications in the field of mental health.
With our current diagnostic criteria, there tends to be a 2 to 40 month delay in actually diagnosing major depression. This can leave people searching for other illnesses and potential causes for feeling crappy. Additionally, since depression is under-diagnosed, it would have potential to provide a quicker diagnosis with superior accuracy.
More Study Details: Depression Blood Testing at Northwestern University (2014)
There were a total of 32 participants in the study, ranging from 21 to 79 years of age. These patients had been clinically diagnosed as having depression. In addition to the 32 depressed patients, there were 32 non-depressed individuals that acted as the “control” group. All of the non-depressed individuals were in the same age range of 21 to 79 year olds.
All of the individuals were simultaneously involved in a study that compared the efficacy of two types of CBT: telephone-based vs. face-to-face. Prior to receiving the therapy, Northwestern researchers were able to pinpoint 9 RNA blood markers that were significantly different among the depressed and non-depressed participants. These specific markers were found to successfully determine which patients were depressed, and which weren’t.
Following 18-weeks of the two variations of CBT, researchers noted that some patients experienced changes in RNA blood marker levels. The changes in blood levels correlated with improvements in depressive symptoms. Those that got no relief from therapy didn’t experience any changes in their RNA blood marker levels.
Individualized RNA markers: Researchers noted that each person tends to have a unique pattern of RNA levels, which can be used to predict how someone will respond to therapeutic approaches. People with specific patterns of RNA at the baseline were found to be either: “good” or “poor” candidates for therapeutic benefits. In the future, analysis of baseline RNA levels could predict who will be responsive to therapy.
Comparing non-depressed RNA vs. formerly depressed RNA
Those who have been diagnosed with major depression and experience recovery from their symptoms still have differences in 3 RNA markers compared to non-depressed individuals. This suggests that even when people achieve remission from depression, they are still susceptible or have a “predisposition” to relapse. The goal of researchers with these specific findings is to identify why these three RNA markers influence depression, which could lead to better treatments, and possibly a cure.
Why a blood test for depression would be beneficial…
Approval of a blood test for depression would be beneficial in a number of ways. It would help us get a better understanding of the severity of a person’s depression and whether medications or treatments are worsening the depression (as is often the case). Additionally it could help us further understand a “placebo” and “nocebo” effect as a result of taking a sugar pill in studies – demonstrating the power that “belief” can influence emotions.
- Placebo / Nocebo effects: Many patients report a “worsening” of depressive symptoms on certain medications. A blood test would be able to determine whether the reports are based in science based on RNA markers or whether they are merely a psychological “nocebo” effect. This type of technology could help us understand whether patients exhibiting an antidepressant effect from a placebo (sugar pill) experience changes in RNA markers.
- Medication response: In the study, it was found that those responding to a medication experienced changes in their RNA marker activity. Therefore it is pretty straightforward to determine whether someone is responding to a certain drug or actually feeling worse. Additionally a better understanding of medication response could help us understand why antidepressants take so long to work and among others antidepressants work immediately.
- Benefit: If a person responds to an antidepressant, researchers are able to see the response within their blood sample. If the drug doesn’t have any benefit for a person, they are able to see that no changes have occurred by analyzing the blood sample.
- Worsening of symptoms: In many cases antidepressants are a total gamble in regards to the effects produced by a specific drug. A certain drug may influence positive changes in one individual’s physiology, but for another person, that same drug may make the person more depressed and lead to unwanted side effects. There is sufficient evidence that some antidepressants can cause suicidality and increased depression; hence the “black box” warnings on each medication.
- Symptom improvement: Perhaps the most interesting aspect of this study was that researchers were able to determine which patients were improving in their symptoms of depression following therapy. Participants that were going to therapy for depression exhibited less RNA markers that would indicate depression. Although they may not have been completely depression-free, their RNA markers indicated that they were significantly less depressed.
- Treatment efficacy: By utilizing a depression blood test doctors would be better equipped to gauge effectiveness of various treatments including therapy and medications. Some people may respond better to medication, others may respond better to therapy, while a third group may respond better to a combined approach. Additionally if multiple drugs are used and both are found effective, it may even be able to determine which one is a “better fit” for the individual.
- Therapy response: This study was able to determine that individuals going to therapy experienced changes in their RNA blood markers. As people who were enrolled in therapy became less depressed, their RNA better reflected that of non-depressed individuals.
- Severity of depression: Early signs indicate that this test will be able to demonstrate the severity of a person’s depression. If a person’s blood stream contains significantly more RNA markers that signify depression, they are likely to be very depressed. If someone contains a mix of depressed and non-depressed RNA activity, they may experience a lower grade of depression. This may help us in diagnosing whether someone has low-grade, moderate, or major depression along a spectrum. Researchers would essentially be able to determine how self-reports of depression severity match up with RNA marker activity.
- Clinical trials: Approving a reliable blood test for depression would help establish whether certain medications are effective in clinical trials. It would be pretty obvious which drugs result in more drastic RNA changes in the bloodstream and which don’t. Researchers would be able to assess RNA before the drug and after the drug to determine whether it results in significant improvement. They would then be able to compare the changes to a non-depressed RNA template of sorts and see how changes occur after taking a certain antidepressant.
- Natural treatments: Most natural antidepressants have been poorly researched in treating depression because they are not created by big pharmaceutical companies. The fact that funds are sufficiently lacking to design a study for these supplements is somewhat troubling. By having this depression blood test, people would be able to determine whether supplementing something like Omega-3 can change RNA activity in the bloodstream. Additionally activities such as exercise and dietary changes may be found to act as natural cures for depression in certain individuals. If blood testing could prove these findings, it would be a huge breakthrough.
- Genetic validation: This study serves to further validate that genetics can be caused by our genetics. It has long been hypothesized that genetics can influence the development of depression, but now it has been confirmed. However, it also shows that with the correct treatment, our genetic activity can be altered to yield improvements in symptoms.
- Happiness testing: Although hearing about how depressed you are as a result of a blood test, it would be interesting to compare individuals that are “happy,” “happier than average,” or “hypomanic” to a normal sample. If there are specific changes in the bloodstream that can be documented, this may pave way to help us understand the spectrum of moods that ranges from being “severely depressed” to experiencing “mania” (at the opposite “pole” of the spectrum).
Blood tests for other mental illnesses?
Having a blood test for depression would be great because if effective, it may pave the way for diagnosing other mental illnesses via blood test. What if we were able to utilize blood work to determine anxiety disorders, schizophrenia, bipolar disorder, etc.?
Lead researcher Redei mentioned that she wants to eventually test to determine differences between standard depression and bipolar depression. This would be groundbreaking to say the least. As future technology continues to improve and humanity advances in medical knowledge, it will further increase our understanding of various diseases and proper diagnoses.
Could this influence future treatments?
Some speculate that these findings will need further validation from future studies before a test gets approval by the FDA. However, assuming that this test goes on to get approved by the FDA and is very accurate, it could actually open up doors for new treatment options. Scientists may be able to come up with a way to identify the RNA markers and possibly the DNA influencing the changes, and eventually devise medications (or gene therapy) to target them.
Of course, this may be wishful thinking (in our lifetime), but at the very least, the test could be used as a more accurate, scientific way to diagnose “mental illness.” Based on current findings in the field of depression and other mental illness, researchers are discovering that genetic modulations play a huge role in the development of nearly every disease. As more research is conducted, individualized treatments, diagnoses, and prognoses will become the mainstream.
When will blood tests for depression become available?
Currently more research needs to be conducted before blood tests for depression are introduced into the mainstream. More evidence needs to show that these tests are highly effective before a doctor can rely on the testing to determine whether someone is actually depressed. Preliminary evidence is very promising, but the FDA would need to compile more data before they grant approval for this testing.
My guess is that within the next decade or so a blood test will become available. If initial results suggest a high degree of validity and reliability, the testing may get fast-track approval from the FDA. A lead researcher was quoted as saying that this is, “An important first step” because it holds the “potential to quickly identify depression in patients and develop faster, more effective treatment.” Expect this type of testing to become the mainstream by 2030.
- Source: http://www.nature.com/tp/journal/v4/n9/full/tp201466a.html