Abstract MP75: Glycemia (Hemoglobin A1c) is Not Related to Incident Venous Thromboembolism in the Atherosclerosis Risk in Communities Study

Abstract

Introduction— Diabetes has been inconsistently associated with increased risk of venous thromboembolism (VTE). Glycemia is positively associated with coagulation activation and hypofibrinolysis, resulting in a procoagulant state. However, there is little direct evidence on associations of glycemia with VTE. Hypothesis— Glycemia, as measured by hemoglobin A 1c (A 1c ), is positively associated with incident VTE over a follow-up period of 15 years. Methods— The Atherosclerosis Risk in Communities (ARIC) study is a population-based cohort study of middle-aged adults followed for 15 years after visit 2, when A 1c was measured. Because A 1c is affected by treatment in diagnosed diabetics, separate analyses were conducted for individuals with diagnosed diabetes. Diagnosed diabetes was defined as taking diabetes medication or a history of diabetes (self-report). We assessed the relation between A 1c and incident VTE during follow-up using Cox proportional hazards models, controlling for potential confounders: age, sex, race, smoking status and amount, hormone use, body mass index, and waist-to-hip ratio. Results— The cohort free of VTE and/or anticoagulant use in 1990-1992 included 11,976 participants without a diagnosis of diabetes (317 VTE events) and 1,040 participants with a diagnosis of diabetes (45 VTE events). As shown in the figure, the adjusted hazard ratio estimates, using participants with an A 1c < 5.70 % and without diagnosed diabetes as the referent, were close to 1, regardless of A 1c level and diabetes diagnosis status. Further, there was no relation in analyses conducted by VTE type (provoked and unprovoked) or in participants with diabetes (both diagnosed and undiagnosed) relative to those without diabetes. Conclusions— In conclusion, although a modest association cannot be ruled out, our findings do not support an association between A 1c and VTE.