Long-term glucose variability and incident cardiovascular diseases and all-cause mortality events in subjects with and without diabetes: Tehran Lipid and Glucose Study

Aim To examine whether visit to visit variability (VVV) of fasting plasma glucose (FPG) is associated with incident cardiovascular diseases (CVD) and all-cause mortality in individuals with and without type 2 diabetes (T2D). Methods A total of 4756 participants aged ≥30 years entered the study in 2002–2005 and underwent two subsequent examinations in 2005–2008 and 2008–2011. FPG variability measures included standard deviation (SD), coefficient of variation (CV), average real variability (ARV), and variability independent of mean (VIM). Multivariate Cox proportional hazard models were used to assess the risk of incident CVD and all-cause mortality for each unit increase in different FPG variability measures. Results During a median follow-up of 18.14 years after baseline recruitment, 492 incident cardiovascular diseases and 338 all-cause mortality were recorded. Among individuals without T2D, the multivariate-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for incident CVD were 1.02 (1.01–1.04), 1.02 (1.01–1.04), 1.01 (1.00–1.02), and 1.01 (1.00–1.01) for SD, CV, ARV, and VIM, respectively (all P-values <0.05). Among individuals with T2D, the corresponding HRs and 95% CIs for all-cause mortality were 1.01 (1.00–1.02), 1.02 (1.01–1.03), 1.01 (1.00–1.02), and 1.01 (1.00–1.01), respectively (all P-values <0.05). Conclusion Long-term (VVV) of FPG is significantly associated with increased risk of CVD among participants without T2D, and all-cause mortality among participants with T2D.