Abstract

Major depressive disorder (MDD) is a psychiatric illness with growing psychosocial concern, intensified by socio-economic and political stressors. Depression is associated with hyperactivity of the hypothalamo Pituitary Adrenal(HPA) axis. Meanwhile, dysregulation of HPA axis has also been reported in substance abuse disorder.
Aim
To evaluate serum cortisol levels among patients with major depressive disorder, patients with substance abuse disorder, and healthy controls, in order to determine the presence of HPA axis dysregulation.
Materials and method
This was a prospective cross sectional pilot study carried out in 2 mental health facilities in Benin city in July 2024. 33 subjects participated in the study. 13 diagnosed with MDD, 10 diagnosed with substance abuse disorder and 10 healthy controls. Serum cortisol was assayed using Quantitative immunoflourescence method. Fasting plasma glucose was assayed by glucose oxidase method. Statistical Analysis used SPSS 26 with t-tests and Pearson’s correlation; Level of significance at p≤0.05.
Results
Mean serum cortisol was significantly higher in MDD subjects (345.91±195.45nmol/L) compared with controls (203.38±63.46) p=0.03. Similarly, mean serum cortisol was higher in Substance abuse subjects (268.47±150.23nmol/l) compared with controls (203.52±63.46 nmol/l); however the difference was not statistically significant (p=0.38). In addition, mean fasting plasma glucose was higher in MDD (105.30±30.96) then in controls (92.80±17.88) although not statistically significant (p=0.59). In substance abuse subjects, fasting plasma glucose was also higher(98.33±18.72) then in controls (92.80±17.88) but also not statistically significant (p=0.79).
Conclusion
The significantly elevated serum cortisol observed in subjects with MDD, and the higher but non-significant cortisol levels in subjects with substance abuse disorder, suggest possible HPA axis dysregulation. Although fasting plasma glucose levels were higher in both patient groups, the differences were not statistically significant, indicating a trend that may be related to stress-associated hormonal changes and requires further investigation in larger studies.