Lower-than-normal glycemic levels to achieve optimal reduction of diabetes risk among individuals with prediabetes: A prospective cohort study

Aims/hypothesis: To determine whether lower than currently accepted glycemic levels could lead to optimal risk reduction of incident diabetes among individuals with prediabetes.Methods: We enrolled 9903 individuals with prediabetes and 16,902 individuals with normoglycemia from a prospective cohort participating health check-ups between 2006 and 2017. While classifying fasting glucose into <5.0, 5.0-5.5, and 5.6-6.9 mmol/L and postprandial glucose into <6.7, 6.7-7.7, and 7.8-11.0 mmol/L, we grouped fasting/postprandial glucose into five categories (<5.0/<6.7, <5.0/6.7-7.7, 5.0-5.5/<6.7, 5.0-5.5/ 6.7-7.7 mmol/L, 5.6-6.9/7.8-11.0 mmol/L). The primary outcome was incident diabetes.Results: In individuals with prediabetes, the presence of a baseline fasting glucose <5.0 mmol/L or a postprandial glucose <6.7 mmol/L led to a greater risk reduction of incident diabetes with hazard ratios of 0.34 (95% con-fidence interval, 0.27-0.42) and 0.47 (0.41-0.54), respectively, relative to a fasting glucose 5.6-6.9 mmol/L and a postprandial glucose 7.8-11.0 mmol/L. For individuals with prediabetes having fasting/postprandial glucose <5.0/<6.7 mmol/L, the incidence of 6.4 (4.7-8.8) per 1000 person-years corresponded to that of 5.8 (4.2-8.0) per 1000 person-years for individuals with normoglycemia having 5.0-5.5/6.7-7.7 mmol/L. Conclusions/interpretation: Given that lower-than-normal glycemic levels were plausible for optimal risk reduc-tion of diabetes, stringent glycemic management could be beneficial for diabetes prevention among individuals with prediabetes.

Automated summary

Lower glycemic levels than currently accepted could lead to optimal risk reduction of incident diabetes among individuals with prediabetes, highlighting the importance of stringent glycemic management for diabetes prevention.