Prediabetes, Diabetes, and the Risk of All-Cause and Cause-Specific Mortality in a Japanese Working Population: Japan Epidemiology Collaboration on Occupational Health Study
<b>Objective:</b> Prediabetes has been suggested to increase mortality risk; however, the definitions of prediabetes that can predict mortality remain elusive. We prospectively investigated the association of multiple definitions of prediabetes with the risk of mortality from all-causes, cardiovascular disease (CVD), and cancer in Japanese workers. <p> </p> <p><b>Research</b> <b>design</b> <b>and</b> <b>methods:</b> The study included 62,785 workers who underwent a health checkup in 2010 or 2011 and were followed up for mortality from 2012 to March 2019. <a>Prediabetes was defined according to fasting plasma glucose (FPG) or glycated hemoglobin (HbA1c) level or a combination of both using the American Diabetes Association (ADA) or World Health Organization (WHO)/International Expert Committee (IEC) criteria. </a>The Cox proportional hazards regression model was used to investigate the associations.</p> <p> </p> <p><b>Results:</b> Over a 7-year follow-up, 229 deaths were documented. <a>Compared with normoglycemia, prediabetes defined according to ADA criteria was associated with a higher risk of all-cause (hazard ratio [HR] 1.53; 95% confidence interval [CI] 1.12–2.09) and cancer (HR 2.37; 95% CI 1.45–3.89) mortality but not with CVD mortality. </a>The results were materially unchanged when prediabetes was defined according to ADA FPG, ADA HbA1c, WHO FPG, or combined WHO/IEC criteria. Diabetes was associated with the risk of all-cause, CVD, and cancer mortality.</p> <p> </p> <p><b>Conclusion:</b> In a cohort of Japanese workers, FPG- and HbA1c-defined prediabetes according to ADA or WHO/IEC was each associated with a significantly increased risk of mortality from all-causes and cancer but not CVD. </p>