In the medical field, it has essentially been a guessing game of knowing which antidepressants should be prescribed to a patient. According to new research, this is no longer the case. Doctors can now decide for the first time which medication is more likely to help a patient overcome depression.
Physicians have had to rely heavily on patient questionnaires to choose a treatment. According to Dr. Madhukar Trivedi, who led the research at UT Southwestern Medical Center’s Center for Depression Research and Clinical Care, they have now developed a blood test that measures a specific type of protein level, thereby providing an immediate tool for determining which treatment would be most effective.
Dr. Trivedi is a director of the depression center, a cornerstone of UT South Western’s Peter O’Donnell Jr. Brain Institute. He explained that the selection of depression medications is currently no more superior than flipping a coin. With this new development, a biological explanation to guide treatment of depression is now available.
Trivedi is a Professor of Psychiatry and holds the Betty Jo Hay Distinguished Chair in Mental Health. He is also the inaugural holder of the Julie K. Hersh Chair for Depression Research and Clinical Care.
The study showed that by measuring the C-reactive protein (CRP) levels of a patient through a simple finger prick blood test, doctors could determine and prescribe a medication that is more likely to work. A significant boost in the success rate of depressed patients who frequently struggle to find effective treatments is expected when this test is utilized in clinical visits.
Trivedi led a major national study more than a decade ago. The study gave insight into the prevalence of the problem. It found that up to 30% of depressed patients don’t improve after their first medication regime, while about 40% of people who start taking antidepressants, stop taking them within three months. The study did however establish widely accepted treatment guidelines for depressed patients.
Trivedi noted that this happens because the patients give up and added that a central symptom of the disease is losing hope. Patients are however more likely to continue the treatment and achieve the benefit if outcomes are improved by tying treatment selection to a blood test.
The new research was published in Psychoneuroendocrinology. Remission rates of more than 100 depressed patients that were prescribed with either escitalopram plus bupropion, or escitalopram on its own, was measured.
A strong correlation was found between the CRP levels found in patients, and the drug regimen that relieved their symptoms:
- For patients with CRP levels higher than 1 milligram per liter, escitalopram plus bupropion was more likely to work. This led to a 51% remission rate compared to 33% rate if they used escitalopram alone.
- For patients whose CRP levels were less, escitalopram alone was more effective with a 57% remission rate compared to less than 30% on the other drug.
Trivedi believes that these results could readily be applied to other commonly used antidepressants. He also noted that the findings prove that a biological test can be used in clinical practice immediately.
CRP was identified as a potential marker for depression treatments as it has been used as a measure of inflammation for other disorders such as diabetes and cardiovascular disease effectively.
Previous research to establish CRP as an antidepressant marker used levels three to five times higher than what was used in this study. Trivedi however felt that patients would experience the sickness of depression with a much lower level of inflammation.
Larger studies will now be undertaken to verify CRP’s role with other antidepressants. Where CRP does not prove effective, alternative markers will have to be found. Trivedi is of the opinion that these studies may lead to other biological tests that can be used in practice.
Trivedi noted that patients and primary care providers are both urgently looking for markers that would indicate there is some biology involved in this disease. Else, treatments are determined from questions and answers from the patients, and that is simply not good enough.