A systematic review and meta-analysis of serum and plasma cortisol levels in depressed patients versus control

Depression is associated with hyperactivity of the hypothalamo pituitary adrenal axis. Cortisol is a steroid hormone, released from the adrenal gland and is considered to be a biological marker of stress and anxiety. Serum or plasma cortisol levels have been previously studied in depressive patients but reported contradictory results. The present meta analysis aims to assess the serum or plasma concentration of cortisol in depressive patients compared with controls. We have conducted a systematic review with sequential meta analysis according to the Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) guidelines. Web of Science, PubMed, Scopus, and PsycINFO databases, and published reference lists were searched up to January 2021. We have conducted a systematic review on PubMed for the following search (MeSH) terms ("Hydrocortisone"[Mesh]) AND "Depressive Disorder"[Mesh]). The RevMan 5.3 and Open Meta Analyst software was used with the standard mean difference (SMD) and 95% confidence intervals (CIs). The Jamovi and Open Meta Analyst Software were used to evaluate the publication bias, sensitivity analysis, and meta regression as possible sources of heterogeneity. Seventeen studies having a combined population (n) of 1400 (743 depressive patients and 657 controls) had satisfied the inclusion criteria for serum or plasma cortisol. The pooled SMD of the serum or plasma cortisol levels in depressive patients compared with controls was 1.18, (95% CI: 0.84, 1.52; P < 0.00001) with I2 = 85% (Ph < 0.00001). This meta analysis indicates a statistically significant mean difference in serum or plasma cortisol between depressed patients and controls. Meta analysis concluded that serum or plasma cortisol can differentiate depressed patients from nondepressed controls.