C-reactive protein and cortisol in drug-naïve patients with short-illness-duration first episode major depressive disorder: Possible role of cortisol immunomodulatory action at early stage of the disease

BackgroundHypercortisolemia and low grade systemic inflammation are observed in major depressive disorder (MDD). Studies on markers of systematic inflammation and Hypothalamic-Pituitary-Adrenal (HPA) axis dysregulation in MDD produce confounded results due to heterogeneity of MDD patients related to illness stages and severity with a large proportion suffering from remitted-recurrent and treatment-resistant/chronic depression with first-episode major depression being underrepresented. This study was designed to examine whether and to what extent CRP is related to baseline cortisol concentrations in a well defined cohort of short-illness-duration first-episode, treatment-naïve MDD patients.MethodsThe levels of salivary C-reactive protein (CRP) and baseline plasma cortisol concentrations were studied in this cross-sectional case-control study on 20 non-late-life adult, treatment- naïve MDD patients with short-illness-duration first affective episode and in 20 age- and sex-matched healthy controls. Depressed patients showed a basal score in the Hamilton Rating Scale for Depression (HAMD-17) higher than 20.ResultsNo significant difference in CRP concentration between MDD and control groups was found. Significantly higher baseline cortisol (p=0.01) concentration was observed in MDD as compared to controls. Significant positive correlation was found between cortisol and CRP levels both in MDD subjects (r=0.57; p=0.008) and controls (r=0.61; p=0.004).LimitationsThe current study is limited by its cross-sectional design and small sample size.ConclusionThe study supports data on elevated cortisol concentration in MDD providing no evidence for elevated CRP levels at the early stage of the disease.