Dr. Marie Kim Wium-Andersen of Herlev Hospital and Copenhagen University Hospital in Denmark and colleagues examined whether elevated plasma levels of CRP were associated with distress and depression.
CRP is linked to an increased risk of diabetes, hypertension and cardiovascular disease.
Researchers analyzed CRP levels using data from two general population studies in Copenhagen, which included 73,131 men and women ages 20-100.
"The main finding of this study consisted of an association of elevated CRP levels with an increased risk for psychological distress and depression in the general population," the authors said.
The study, published Online First by Archives of General Psychiatry, increased CRP levels were associated with increasing risk for psychological distress and depression in analyses.
"More research is needed to establish the direction of the association between CRP and depression because this study and others are primarily cross-sectional," the study authors said in a statement. "The results also support the initiation of intervention studies to examine whether adding anti-inflammatory drugs to antidepressants for treatment of depression will improve outcome."