OBJECTIVEAlthough increasing evidence suggests the association between short-term variability of fasting plasma glucose (FPG) and diabetic complications or mortality, the impact of visit-to-visit variability of FPG on the development of type 2 diabetes (T2D) has not been evaluated.
RESEARCH DESIGN AND METHODSOur analysis included 131,744 Korean men and women without diabetes using the Korean National Health Insurance System cohort with periodic health examination program. FPG variability was calculated using the coefficient of variation (FPG-CV), SD (FPG-SD), and variability independent of the mean (FPG-VIM).
RESULTSDuring the median follow-up time of 8.3 years, Kaplan-Meier curves demonstrated lower disease-free probability in the higher FPG variability group compared with the lower FPG variability group. Multivariable Cox proportional hazards analysis exhibited that the hazard ratio for incident T2D was 1.67 (95% CI 1.58-1.77, P < 0.001) in the highest quartile of FPG-CV compared with the lowest quartile of FPG-CV after adjusting for confounding variables, including mean FPG. The association between FPG variability and the risk of T2D was consistent when modeling using FPG-SD and FPG-VIM in both normal and impaired fasting glucose groups. A 1 SD increase in the FPG-CV was associated with a 24% increased risk of T2D in the fully adjusted model.
CONCLUSIONSIncreased variability of FPG is associated with the development of T2D independently of diverse risk factors.Glycemic variability has recently drawn attention as another aspect of glycemic control and may contribute to additional risk of diabetic complications independent of hemoglobin A 1c (HbA 1c ) (1). Several human studies (2,3) suggested an association between glycemic variability and all-cause/cardiovascular mortality in patients with type 2 diabetes. Interestingly, mean fasting plasma glucose (FPG) level was not significantly associated with mortality in a multivariate analysis after adjusting for the coefficient of variation (CV) of FPG (3). In addition, long-term FPG variability was