Fasting Glycemic Variability Indicates Increased Risk for Type 2 Diabetes

A greater variation of fasting plasma glucose over time is associated with an increased risk of developing type 2 diabetes, according to a study published in Diabetes Care.

The researchers analyzed data from the Korean National Health Insurance System on 131,744 participants without diabetes at baseline for fasting plasma glucose levels and the development of type 2 diabetes over a median follow-up time frame of 8.3 years. The database contained information regarding medical history, ICD-10 codes, health-related variables, questionnaires, blood work analysis, and laboratory testing. 

Fasting plasma glucose coefficient of variation, standard deviation, and variability independent of the mean were indices used to calculate fasting glucose plasma variability. Type 2 diabetes was defined as a fasting glucose plasma level ≥7 mmol/L, and impaired glucose was defined as a fasting glucose plasma level between 5.6 mmol/L and 6.9 mmol/L.

Overall, the participants with higher fasting glucose plasma level variation were older males who smoke, drank, completed little physical activity, and had a higher occurrence of hypertension and dyslipidemia. After adjusting for confounding variables, the hazard ratio for fasting glucose plasma coefficient of variation was 1.24 (95% CI, 1.22-1.27; P <.001). Additionally, the hazard ratio for fasting glucose standard deviation was 1.23 (95% CI, 1.20-1.25; P <.001) and the ratio for fasting glucose variability independent of the mean was 1.23 (95% CI, 1.21-1.26; P <.001). For fasting plasma glucose coefficient of variation, an increase of 1 standard deviation resulted in a 24% risk increase for developing type 2 diabetes.

Investigators recommended that future studies include a more diverse population to draw further encompassing results, utilize other diabetic diagnostic tools such as oral glucose tolerance tests or HbA1c results, and include dietary behaviors as a variable. 

The researchers concluded that “there were clear associations of [fasting glucose plasma] variability with increased risk [for] type 2 diabetes” independent of other confounding variables.

Reference

Kim JA, Lee JS, Chung HS, et al. Impact of visit-to-visit fasting plasma glucose variability on the development of type 2 diabetes: a nationwide population-based cohort study [published online Sept. 25, 2018]. Diabetes Care. doi:10.2337/dc18-0802