Depression may not allow the anti-inflammatory effects that we usually get when we engage in physical activity, according to researchers at Duke Medicine.
CRP is a biomarker that predicts future risk of heart disease and other chronic inflammatory conditions. It may also build up plaque in the arteries. Lower the CRP, lesser the risk of heart disease. When we do light exercises, our CRP reduces.
Lead author Edward C. Suarez, PhD, associate professor of psychiatry and behavioral sciences at Duke Medicine investigated CRP levels and its association to depression.
His team gathered information from 222 non-smoking, healthy adults with no history or diagnosis of psychiatric conditions. Participants also informed them about the number of hours of physical activity they did in the previous week [walking, playing tennis, and exercise classes]. Researchers measured CRP levels through blood samples and assessed the participants’ depressive symptoms. It turned out with 4.5 per cent of the study group met the criteria for depression.
The study revealed that untreated depression hindered in the anti-inflammatory effects of exercise. Those who were physically active had lower CRP levels, with the exception of those who were depressed. The depressed individuals saw no lowering of CRP levels even though they had exercised.
“This is a novel finding, and it seems to be specific to inflammation as measured by CRP,” Suarez said, given that depression did not affect other health markers such as fasting triglyceride and cholesterol levels.
Early intervention – and perhaps more aggressive treatment for depression – may help patients who do not see the benefit of heart-healthy activities due to untreated depression.
“We’re not saying that exercise isn’t helpful for those with depression; what we saw is that depression has effects beyond what has previously been reported. Even if mental health improves, the anti-inflammatory benefits of physical activities may lag behind,” Suarez said.
The study results were published online in the journal Brain, Behavior, and Immunity.