Context: The immune system has an important role in the etiology of depression, through the pro-inflammatory cytokines and acute phase protein mechanisms. In elderly people, frequent association between depression and medical conditions leads to a difficult psychiatric diagnosis, becoming necessary to determine a specific biological marker for this category of population. C-Reactive Protein (CRP) did not prove to have a high level of validity, but higher levels of high-sensitivity C-Reactive Protein (hs-CRP) were found to be associated both with cardiovascular disease and depressive disorder, through a bidirectional relationship.
Objectives: To investigate the possible association between a major depressive episode and levels of inflammatory markers among a population of elderly.
Subjects and methods: A prospective study on a sample of 82 individuals aged over 65 years, who presented for laboratory evaluations in an outpatient setting. They were recorded socio-demographic and clinical data; depression and anxiety were assessed using the Hospital Anxiety and Depression Scale. Blood samples were collected and analyzed according to the protocol of the study.
Results: Anxiety, identified in 57 persons, was not statistically significant correlated with the levels of inflammatory markers. For depressive disorder (37 subjects), both CRP and hs-CRP were significantly higher, with an almost medium effect size.
Conclusions: The high levels of CRP and hs-CRP are associated with the presence of depression in elderly patients, but not with the anxiety. Further and complex studies need to validate these findings on this group of age.
Keywords: biomarker; depression; elderly.