Nearly one-third of patients with type 2 diabetes have subclinical or silent cardiovascular disease (CVD) indicated by raised levels of high-sensitivity cardiac troponin T (hs-cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) compared to those who do not have diabetes, according to a study published online May 31, 2023 in the Journal of the American Heart Association. The high burden of subclinical CVD in this patient group considerably increased mortality risk even after adjustment for demographic and traditional CV risk factors like smoking, high BP/cholesterol, overweight or obesity and a positive family history of heart disease.

Researchers from Johns Hopkins University and University of Maryland Medical Center in Baltimore, United States sought to examine the prevalence of subclinical cardiovascular disease. For this they sourced data of 10,304 participants without a history of CVD from the 1999-2004 National Health and Nutrition Examination Survey (NHANES). For this, they measured the levels of hs-cTnT (high-sensitivity cardiac troponin T) and NT-proBNP (N-terminal pro-B-type natriuretic peptide) in the stored serum samples and estimated the prevalence of raised levels of these biomarkers among those with diabetes and without diabetes. The cut-offs to diagnose CVD were hs-cTnT (≥14 ng/L) or NT-proBNP (≥125 pg/mL).

The study group was categorized as having no diabetes, newly diagnosed diabetes (≤1 year or no self-reported diagnosed diabetes and HbA1c ≥6.5%), short diabetes duration (self-reported diagnosis between 1 and 10 years) and long diabetes duration (≥10 years).

On analysis, 33.4% patients with diabetes had higher prevalence of either raised hs-cTnT or NT-proBNP levels compared to 16.1% of those who did not have diabetes; 19% had elevated levels of hs‐cTnT and 23% had elevated NT‐proBNP levels. Adults with diabetes were also more likely to have elevated levels of both biomarkers compared to those without diabetes (9% versus 3%). But after adjusting for age, sex, race/ethnicity and traditional CVD risk factors, only raised hs-cTnT was found to be positively associated with diabetes. Those who had long-standing diabetes and poorly controlled diabetes were more likely to have significantly elevated hs-cTnT levels.

Researchers also studied the associations between the two raised biomarkers and all-cause mortality as well as CVD-related mortality, whether heart disease or cerebrovascular disease. After adjustment for demographics and traditional cardiovascular risk factors, elevated hs-cTnT levels were associated with 77% increased risk of all-cause mortality with adjusted hazard ratio (aHR) of 1.77 and elevated NT-proBNP were associated with 78% increased risk with aHR 1.78. The risk of CVD-related mortality was increased 54% for elevated hs-cTnT with aHR of 1.54 and the increase in risk was more than 2-folds for NT-proBNP (aHR 2.46).

This study shows that many patients with type 2 diabetes who do not have a diagnosed heart disease are still at high risk of developing cardiac complications such as heart attack, stroke, heart failure. It further suggests that cardiac biomarkers, hs-cTnT in particular, should routinely be measured in patients with type 2 diabetes to assess and monitor their risk for heart disease along with other traditional CV risk factors. Doing so will enable timely institution of preventive strategies for patients with type 2 diabetes at higher risk.

Reference

1. Fang M, et al. Subclinical cardiovascular disease in US adults with and without diabetes. J Am Heart Assoc. 2023 May 31;e029083. doi: 10.1161/JAHA.122.029083.