High blood sugar in type 1 diabetes tied to cardiac autoimmunity: Circulation

Key findings of the study include:

• Although the recent HbA1c levels were similar among participants with and without cardiac autoantibodies, the presence of cardiac autoantibodies identified those with worse glycemic control in the past, suggesting that cardiac autoantibodies are markers of long-term glycemic exposure.
• Participants with more autoantibody types had more pronounced changes to the heart.
• There was a markedly greater numbers of autoantibodies in the HbA1c greater than 9% group compared with the less than 7% group.
• 46% of subjects had more than one antibody, 22% had greater than two antibodies, vs. only 2% and 1%, respectively, in the HbA1c less than 7% group.
• No subject in the HbA1c less than 7% group had three or more antibodies.
• There was a similarity in profiles when comparing the DCCT participants with an HbA1c of at least 9% with a separate cohort with heart failure from Chagas cardiomyopathy that is believed to be driven by a form of chronic myocarditis with autoimmunity against alpha-myosin.
• The DDCT low HbA1c group resembled control subjects.
• There was no relationship between blood sugar control and cardiac antibodies in a cohort of people with type 2 diabetes and comparable glycemic control.
• DCCT participants with the highest titers and numbers of cardiac autoantibodies developed CVD events up to 26 years later.
• A single, fatal CV event occurred in the only DCCT participant to test positive for all five antibodies.
• Analyses stratified by number of cardiac autoantibodies also showed that the presence of two autoantibodies was also associated with a threefold increased high sensitivity C-reactive protein (CRP) level, with a median level of 6 mg/L among those with two or more autoantibodies vs. a median high sensitivity CRP of 1.4 mg/L among participants with one or fewer antibodies.