Poster Presentation Australian Diabetes Society and the Australian Diabetes Educators Association Annual Scientific Meeting 2016

The Effect Of Salt Versus Placebo Supplementation On Haematocrit Levels In Type Two Diabetes Mellitus (#321)

Adrian Michalopoulos 1 , Sara Baqar 1 2 , George Jerums 1 2 , Renata Libianto 1 , Richard MacIsaac 3 , Angela Chen 1 , Martin Stebbing 4 , Elif I. Ekinci 1 2
  1. Department of Medicine Austin Health, The University of Melbourne, Faculty of Medicine, Dentistry and Health Sciences
  2. Department of Endocrinology, The Austin Hospital, Melbourne
  3. Department of Endocrinology and Diabetes, St Vincent's Hospital, Melbourne
  4. School of Medical Sciences, RMIT University, Melbourne

We have previously demonstrated that low 24h urinary sodium excretion is associated with higher risk of death. Previous studies have suggested an association between increased haematocrit levels and increased mortality. We hypothesised that higher haematocrit values may be a mechanism explaining the increase in mortality observed in patients with habitual low salt intakes. We aimed to investigate whether haematocrit levels decrease following acute salt supplementation. Patients with type 2 diabetes on a habitually low salt diet as defined by urinary sodium excretion less than 150mmol/24h in two out of three 24-hour urine collections were recruited in two crossover studies (n=32). Patients received salt (100mmol NaCl/24h) versus placebo supplementation for a period of two weeks in study 1 and three weeks in study 2. Haematocrit levels were measured at the end of each period. Salt supplementation did not result in a reduction in haematocrit level (placebo 0.400L/L, NaCl 0.403L/L, P=0.78) or haemoglobin (placebo 138g/L, NaCl 137g/L, P=0.34). Our preliminary data indicates that acute alterations in salt intake are not associated with significant changes in haematocrit level. Further studies are necessary to investigate the mechanisms that link a habitual low dietary salt intake with mortality in patients with diabetes.