Abstract
Background & Aims
Hepatic enzymes play a major role in the metabolic elimination of cortisol, and reduced rates of cortisol clearance have been consistently observed in patients with chronic liver disease. It is less clear whether there are concomitant abnormalities of adrenocortical function in patients with cirrhosis. In the present study, we sought to assess adrenocortical function in patients with cirrhosis using measures of free cortisol appearance and elimination rates that are independent of serum concentrations of cortisol binding proteins.
Methods
Post hoc analysis used computer-assisted numerical and modelling methods with serial total and free cortisol concentration data to obtain rates of free cortisol appearance and elimination. Rate parameters were obtained in 114 patients with chronic liver disease, including Child-Pugh (CP) ≤8 (n = 53) and CP >8 (n = 61).
Results
Maximal cortisol secretion rate (CSRmax) was significantly decreased (p = 0.01) in patients with cirrhosis with CP >8 (0.28 nM/s; 95% CI 0.24–0.34) compared with those with CP ≤8 (0.39 nM/s; 95% CI 0.33–0.46), and CSRmax was negatively correlated with CP score (r = −0.19, p = 0.01). Free cortisol elimination rate was significantly (p = 0.04) decreased in the CP >8 group (0.16 ± 0.20 min−1) compared with that in the CP ≤8 group (0.21 ± 0.21 min−1), and free cortisol elimination rates were negatively correlated with CP score (r = −0.23, p = 0.01). A significant correlation between CSRmax and free cortisol elimination rate (r = 0.88, p <0.001) was observed.
Conclusions
CSRmax and free cortisol elimination rates were significantly reduced according to severity of cirrhosis. In contrast to stimulated total cortisol concentrations, CSRmax estimates were independent of cortisol-binding protein concentrations. Results provide additional evidence of subnormal adrenocortical function in patients with cirrhosis.
Lay summary
We applied numerical analytic methods to characterise adrenocortical function in patients with varying stages of chronic liver disease. We found that patients with more severe cirrhosis have decreased rate of free cortisol elimination and decreased maximal cortisol secretion rate, which is a measure of adrenocortical function. In contrast to conventional measures of adrenocortical function, those obtained using numerical methods were not affected by variation in corticosteroid binding globulin and albumin concentrations. We conclude that patients with cirrhosis demonstrate measurable abnormalities of adrenocortical function, evidence of which supports aspects of the hepatoadrenal syndrome hypothesis.
Free cortisol appearance and elimination rates were obtained by computer-assisted numerical analysis.
Maximal cortisol secretion rates, a measure of adrenocortical function, were inversely related to severity of cirrhosis.
Variation in concentrations of cortisol binding proteins bias measures of adrenocortical function that rely on total cortisol.
Chronically reduced rate of free cortisol elimination in patients with cirrhosis may contribute to the pathophysiology of subnormal adrenocortical function.
Evidence of subnormal adrenocortical function supports the hepatoadrenal syndrome hypothesis.
Collapse