Investigating the Relationship Between Cortisol, a Stress Marker, and Immune Function Across Age and Gender

This study investigates the relationship between cortisol, a well-known stress marker, and immune function, focusing on how cortisol levels affect immune responses across different age groups and genders. Stress can be acute or chronic, both of which influence physiological processes in the body. Cortisol plays a key role in this process, with acute stress leading to brief elevations of cortisol that can enhance immune function, while chronic stress leads to dysregulation and immune suppression. This retrospective study, conducted at a tertiary care hospital, analyzed data from patients who underwent cortisol and complete blood count (CBC) tests between April and September 2024. The data, collected from both male and female participants of various age groups, revealed significant correlations between cortisol levels and immune parameters like total leukocyte count (TLC), lymphocyte percentage, and neutrophil percentage. Notably, cortisol was positively correlated with TLC, while it showed a weak negative correlation with lymphocyte percentage, suggesting a potential reduction in immune responsiveness with elevated cortisol levels. Gender differences were also observed, with females exhibiting a stronger negative correlation between age and lymphocyte percentage, while males showed significant correlations between cortisol levels and immune markers. These findings underscore the complex interplay between stress, cortisol, and immune function, providing insights into stress-related health conditions such as infections and autoimmune disorders.