Visit-to-visit fasting blood glucose variability and lifetime risk of cardiovascular disease: a prospective study

Aims Previous studies suggested an adverse association between higher fasting blood glucose (FBG) variability and cardiovascular disease (CVD). Lifetime risk provides an absolute risk assessment during the remainder of an individual's life. However, the association between FBG variability and the lifetime risk of CVD is uncertain. Objective We aimed to investigate the effect of the visit-to-visit FBG variability on the lifetime risk of CVD. Methods This study included participants from the Kailuan Study who did not have CVD at index ages 35, 45, and 55 years. The FBG variability was defined as the coefficient of variation (CV) of three FBG values that were measured during the examination periods of 2006-2007, 2008-2009, and 2010-2011. We used a modified Kaplan-Merrier method to estimate lifetime risk of CVD according to tertiles of FBG variability. Results At index age 35 years, the study sample comprised 46,018 participants. During a median follow-up of 7.0 years, 1889 participants developed CVD events. For index age 35 years, participants with high FBG variability had higher lifetime risk of CVD (32.5%; 95% confidence interval [CI]: 28.9-36.1%), compared with intermediate (28.3%; 95% CI: 25.5 -31.1%) and low (26.3%; 95% CI: 23.0-29.5%) FBG variability. We found that higher FBG variability was associated with increased lifetime risk of CVD in men but not women. Similar patterns were observed at index ages 45 and 55 years. Conclusions Higher FBG variability was associated with increased lifetime risk of CVD at each index age. Focusing on the FBG variability may provide an insight to the clinical utility for reducing the lifetime risk of CVD.