Associations between glycaemic control and activation of the renin-angiotensin-aldosterone system in participants with type 2 diabetes mellitus and hypertension

TP Griffin, D Wall, GA Browne, MC Dennedy, PM O'Shea

Hyperglycaemia increases succinate levels and succinate receptor (GPR91) activation in the kidney resulting in renin release. The aim of our study was to determine if there is an association between glycaemic control as evidenced by glycated haemoglobin (HbA1c) values and activation of the renin-angiotensin-aldosterone-system in patients with type 2 diabetes mellitus (T2DM) and hypertension. A cross-sectional study was conducted at Galway University Hospitals between December 2014 and March 2015. Participants (n=66) were identified following interrogation of the electronic database for patients with T2DM. Baseline clinical demographics, aldosterone, plasma renin activity (PRA), direct renin concentration (DRC), urea and electrolytes, HbA1c, cholesterol, urine sodium and albumin creatinine ratio were recorded. There was a significant positive linear correlation between HbA1c and renin (both PRA (p = 0.002) and DRC (p = 0.008)) and between serum creatinine and aldosterone measured using both radioimmunoassay (RIA) (p = 0.008) and immunochemiluminometric assay (ICMA) (p = 0.008). A significant negative linear correlation was demonstrated between serum sodium (p = 0.005) and DRC (p = 0.015) and between estimated glomerular filtration rate (eGFR) and aldosterone measured using RIA (p = 0.02) and ICMA (p = 0.016). A significant negative linear correlation existed between urine sodium and PRA (p = 0.040) and aldosterone measured using RIA (p = 0.045). There is a direct positive association between glycaemic control and renin. We advocate for renin measurement to be part of the diabetologist's armamentarium to assess, guide and optimise therapeutic strategies in patients with diabetes.