Poster Presentation Australian and New Zealand Obesity Society Annual Scientific Conference 2023

Associations of glucose variability and nocturnal blood pressure dipping in individuals at risk of developing type 2 diabetes. (#237)

Rasha Charrouf 1 2 , Evelyn B Parr 3 , Amy T Hutchison 1 2 , Steve A Flint 4 , Lijun Zhao 1 2 , Xiao Tong Teong 1 2 , Gary Wittert 1 2 , Leah Brennan 5 , Brooke L Devlin 6 , John A Hawley 3 , Leonie K Heilbronn 1 2
  1. Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia
  2. Lifelong Health Theme, SAHMRI, Adelaide, SA, Australia
  3. Exercise and Nutrition Research Program, Australina Catholic University, Melbourne, Victoria, Australia
  4. Diabetes Technology Research Group, The University of Melbourne, Melbourne, Victoria, Australia
  5. School of Psychology and Public Health, La Trobe University, Wodonga, Victoria, Australia
  6. School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Queensland, Australia

Background:  Glucose variability increases the risk and severity of diabetes complications. Blood pressure (BP) has a diurnal rhythm which normally declines during nighttime and is defined as nocturnal blood pressure dipping, non-dipping of BP is associated with cardiovascular complications. The aim of this study was to determine the associations between glucose variability and the decline in blood pressure that normally occurs overnight in adults at risk of developing type 2 diabetes.

Methods: Eighty-one participants (Australian diabetes risk assessment score ≥ 15) were fitted with a continuous glucose monitor (FreeStyle LibrePro) and an activity monitor (ActivPal) for two weeks, and an ambulatory BP monitor (OnTrak) for 24-h. Multivariable linear regression models were used to assess the associations between each measure of BP (24-h mean systolic diastolic BP, mean arterial pressure (MAP), and change in these parameters overnight) and glucose variability (standard deviation of mean glucose, mean amplitude of glycaemic excursions (MAGE), and mean of daily glucose differences (MODD)).  Model 1 was unadjusted; model 2 was adjusted for age, sex, and visceral fat mass; and model 3 was additionally adjusted for total (24-h) step count.

Results: Participants (60 females, and 21 males) were aged 59±9 years (BMI 32±4 kg/m2, HbA1c 5.4±0.3%). BP dipping (≤10%>20% dipping) occurred in 59% of the participants, 26% were classified as non-dippers (>10% dipping), 2% as night risers (night-time BP>daytime BP), and 12% as extreme dippers(≤20% dipping). Glycaemic variability in MAGE and MODD was associated with reduced nocturnal diastolic dipping in the unadjusted model. MODD remained significant after multiple adjustments in models 2 and 3.

Conclusions: Day-to-day glucose variability was associated with reduced nocturnal dipping in diastolic BP in adults at risk of developing type 2 diabetes.