P7.5 RELATIONSHIPS BETWEEN 24 HOUR URINARY CORTISOL METABOLITES AND STRUCTURAL CARDIAC AND ARTERIAL INDICES IN PEOPLE WITH OR AT RISK OF TYPE 2 DIABETES

Abstract

Objective: To assess if 24h urinary cortisol metabolite (UCM) profiles are related to structural cardiac and arterial parameters in those with or at risk of Type 2 diabetes mellitus (T2DM). Design and method: 32 participants, 25-77 years, eGFR> 45 mL/min and no serious illness. Urine was collected over 24 hours. 2D echocardiography and arterial stiffness measures [aortic pulse wave velocity (aPWV) by Arteriograph and cardio-ankle vascular index (CAVI) by VaSera] were performed on the collection day. Steroids were extracted from urine and hydrolysed; derivatives were analysed by GC-MS. Results: Seven UCMs were quantified [tetrahydrocortisol (THF), allo-tetrahydrocortisol (a-THF), tetrahydrocortisone (THE), α-cortol (α-col), β-cortol (β-col), α-cortolone (α-cone), β-cortolone (β-cone)]. Left ventricular mass index (LVMI) correlated positively with 24h cortisol:cortisone metabolites (THF+aTHF+αcol+βcol/THE+αcortolone+βcortolone) and negatively with α:β metabolites (αcol+αcortol/βcol+βcortol), when indexed for body surface area (BSA) and height (r=0.37, 0.48 and r=−0.34, −0.49 respectively). Further, there was a positive relationship between LVMIBSA and THF:THE (r=0.35). aPWV but not CAVI was also related to 24h cortisol:cortisone metabolites (r=0.45). All p<0.05. Regression analysis including age, gender, systolic blood pressure (SBP), arterial stiffness (aPWV or CAVI) and body mass index (BMI; only for RWT), showed an independent association between THF:THE and LVMIBSA and LVMIheight and cortisol:cortisone metabolites with LVMIheight, p<0.02. SBP, but not arterial stiffness, was also independently related to LVMIBSA and LVMIheight in all models. Conclusion: Specific 24h UCMs and UCM ratios (from glucocorticoid/mineralocorticoid, 11βHSD and 20αHSD/20βHSD actions) may be structural cardiac biomarkers in those with or at risk of T2DM.