The Association of Cortisol Excretion with Weight and Metabolic Parameters in Nondiabetic Patients with Morbid Obesity.

INTRODUCTION

Cortisol is involved in the regulation of gluconeogenesis and glucose utilization. In morbid obesity (MO), the association of cortisol excretion with metabolic parameters is not well-characterized. In our study, we evaluated cortisol excretion in nondiabetic subjects with MO and its effect on glucose metabolism.

METHODS

We included 1,249 nondiabetic patients with MO (79.8% females, mean BMI 44.9 ± 6.5 kg/m2, mean age 38 ± 11 years). Anthropometric data and cardiovascular risk factors were assessed, and an oral glucose tolerance test for calculation of insulin resistance was performed. Cortisol excretion was assessed on 2 consecutive days (24 h urine specimens).

RESULTS

Regarding cortisol excretion, patients were divided into 3 tertiles (urinary cortisol ≤51.6, >51.6 and <117.6, and ≥117.6 μg/24 h, respectively). Patients in the highest tertile were younger (p = 0.003), more obese (BMI: p = 0.040), had lower diastolic blood pressure ([DBP]; p = 0.012), lower total (p = 0.032) and LDL cholesterol (p = 0.021), fasting (p = 0.049) and 2-h glycemia (p = 0.028), 2-h insulinemia (p = 0.020), and HbA1c (p < 0.001), and a higher estimated glomerular filtration rate (eGFR) (p < 0.001). The glucose (p < 0.001) and insulin (p = 0.011) area under the curve (AUC) were also lower. Urinary cortisol excretion adjusted for age, sex, and eGFR was positively correlated with body weight (BW, beta = 0.076, p = 0.004) and overall glucose tolerance (oral disposition index, beta = 0.090, p = 0.011), and negatively with HbA1c (beta = -0.179, p < 0.001), 2-h glycemia (beta = -0.075, p = 0.032), AUC glucose (beta = -0.103, p = 0.002), and DBP (beta = -0.139, p < 0.001). HbA1c, BW, and DBP remained significant after multivariable analysis.

DISCUSSION/CONCLUSION: Despite being more obese, patients with higher cortisol excretion have a more favorable metabolic profile. These results deserve further attention regarding the respective mechanisms.