A Prospective Observational Study on the Effects of Antidepressant Treatment on Hypothalamic-Pituitary-Adrenal Axis Regulation in Treatment-Resistant Depression

Abstract

Introduction: Dysregulation of Hypothalamic-Pituitary-Adrenal (HPA) axis can reduce the effects of antidepressants. Salivary cortisol level and Hamilton Depression Rating (HAM-D) score can be used to assess the level of improvement in the HPA axis and depressive disorders. Aim: To evaluate the changes in salivary cortisol level and HAM-D score in patients of Treatment Resistant Depression (TRD) and to investigate the association between them. Materials and Methods: The present prospective cohort study was conducted in the Department of Pharmacology and Psychiatry at Pt. JNM Medical College and Dr. BRAM Hospital Raipur (CG) over a period of one year, from June 2014 to June 2015. The participants were 52 diagnosed cases of TRD according to Diagnostic and Statistical Manual of Mental Disorders (DSM IV) criteria, who were taking antidepressant medications for at least four weeks. The salivary cortisol values and HAM-D scoring were done at baseline and follow-up at 8 weeks and 16 weeks and compared by student’s t-test and one-way ANOVA. Results: A significant difference (p<0.001) was noted in the mean salivary cortisol levels (1.15±0.31 and 0.72±0.24) mean HAM-D (29.67±1.43 and 16.26±7.08) scores at baseline and subsequent follow-up respectively. Conclusion: The therapeutic benefit of antidepressants could be due to alteration of HPA axis functioning.