Results of a recent study indicate exercise may be of greater benefit to people diagnosed with depression than earlier thought. After a four year study, the psychiatry department of University of Texas Southwestern Medical Center has found physical training can substitute as a second medication for some patients when a single antidepressant fails to cure their condition. Dr. Madhukar Trivedi is the lead author of the study, recently published in the "Journal of Clinical Psychiatry". In our Monday health segment, he told 90.1's Sam Baker the study stems from a common problem in treating depression.
Dr. Trivedi: Over 70 percent of patients do not achieve full recovery for the first antidepressant. And, in fact, even those who achieve in the short term lose their effect. So there is a very large proportion of patients who will need a second treatment - either addition of another medication, psychotherapy or other things, but that is a large population. And we decided to study if adding exercise at that point is a good idea.
Sam: This notion of exercise as part of the treatment for depression is not a new idea. There've been studies on this for some time, right?
Dr. Trivedi: Absolutely, and our group, we have been looking at exercise as a treatment alone for major repressive disorder or clinical depression. And others have done that, too, and it does work. The challenge is just because exercise works in the real world, people don't automatically use it. So if there is a well-designed study that shows the effects and we can, so to speak, officially derive a prescription for exercise, where we do this under the guidance of the right clinicians, and we give patients real guidance to go about and decide what dose of the exercise to use, as you see our results are powerful in the two things. One is that it works, but the high dose is necessary for a large proportion of patients - that just a stroll in the park is not efficient.
Sam: How does exercise work in this way?
Dr. Trivedi: There are animal studies that looked at the effects of exercise, and there is promising and good data showing that there in neurogenesis as nerve fibers increase in the hippocampus, and this is similar to what you see in antidepressant medications. There is very good pre-clinical data showing that exercise does have an effect on brain function, including improvement in neurotransmitters like serotonin or epinephrine. And then there's the sense of self-efficacy when you engage in a program for exercise, and you succeed, and again, if that is associated with improvement in your mood, then you feel that self efficacy very similar to the self efficacy people feel if they have diabetes and they are told "go exercise" and they succeed and the dose of the treatment is reduced and their symptoms improve, they feel as if they have accomplished something, and that has more of a long sustaining effect.
Sam: What kind of exercise do you find works best?
Dr. Trivedi: It really depends on the patients, although our studies have been aerobic exercise. So we do either bicycle or treadmill or you can actually transmit that into swimming or other aerobic activity. We did our studies with either a treadmill or a stationary bike. But there is no reason to believe any other form of exercise will not work.
Sam: What do you hope will result from this study?
Dr. Trivedi: One is that I think we are beginning to get to a point where we are taking depression as a very serious illness. Until now, we used to think of depression as something that can easily be treated with medication. Well, we are beginning to recognize it as often a lifelong illness for a lot of patients, that we really need to treat the person rather than just the disease or one medication. The second thing is we have to go beyond just medication or just psychotherapy. I think we have to take the patient as a complete person and treat their disease in a number of domains, including exercise. And thirdly, hopefully we will be able to convince health care systems and employers in other places to help us set up systems where you can, so to speak, get a prescription for exercise, so that patients who are wanting and willing to do this will have the assistance to achieve their goals. And another issue with this whole paradigm is whether we can intervene early on in high school and early college years and therefore reduce the need for complicated treatments as we go forward.
Sam: Then again, aren't you talking about having to make people more aware of the early signs of depression?
Dr. Trivedi: Absolutely. We lose 30,000 to 35,000 people to suicide every year because of depression and related illnesses. And we tend not to take the disease seriously, so people don't stay in treatment long enough, and so both of those things may be needed to be expanded so that we can educate the population better.