Abstract
OBJECTIVE: The Diabetes Control and Complications Trial (DCCT)/Epidemiology of Diabetes Interventions and Complications (EDIC) study has demonstrated the beneficial effect of intensive therapy on atherosclerosis and clinical cardiovascular outcomes, while identifying hyperglycemia as a dominant risk factor for type 1 diabetes. The current analyses evaluate the extent to which glycemic exposure influences long-term changes in established risk factors for cardiovascular disease (CVD) among patients with type 1 diabetes. RESEARCH DESIGN AND METHODS: The DCCT study randomized 1,441 participants to receive intensive or conventional diabetes therapy; and after an average of 6.5 years of follow-up, 96% of the surviving cohort enrolled in the EDIC observational study for an additional 20 years of follow-up. Annual visits included a detailed medical history and physical examination. Blood and urine samples were collected and assayed centrally. Longitudinal models for repeated measurements were used. RESULTS: Higher HbA1c level was a significant correlate of the longitudinal changes in all of the traditional CVD risk factors over the 30-year follow-up. The strongest longitudinal associations were among the lipid measurements and concurrent glycemia. CONCLUSIONS: A better understanding of the interrelationships between diabetes-related risk factors and traditional CVD risk factors may assist with the development of targeted treatment regimens for persons with type 1 diabetes who are at risk for CVD.