Association of serum cortisol with critical illness scoring and prognosis in intensive care unit

The prevalence of adrenal insufficiency and association of serum cortisol with prognosis in intensive care unit patients is controversial. Some studies have shown a direct association between serum cortisol and bad prognosis while in other studies no such association has been made. This study was designed to evaluate the association between serum cortisol and prognosis of patients in intensive care unit. This was a cross-sectional study performed on intensive care unit patients of Bou-Ali teaching hospital in Qazvin (Iran) in 2009. Serum cortisol levels were measured before and after injection of cosyntropin. Basal cortisol level below 441 nmol/l was interpreted as adrenal insufficiency. In patients with serum cortisol between 441 and 938 nmol/l following injection of cosyntropin the level of serum cortisol was re-measured after 60 min. Patients with serum cortisol response less than 255 nmol/l were interpreted as having partial adrenal insufficiency. Later, patients were divided into 4 groups based on APACHE scoring system. Association of serum cortisol with APACHE score, hypotension, intubation, and mortality was evaluated. Of 60 patients under study, none found to have adrenal insufficiency. Serum cortisol was independently associated with mortality, hypotension, and intubation. Based on results found through this study, Adrenal insufficiency was not common in ICU patients and serum cortisol could be used as a predictor of prognosis.