The analysis of adults with Type 2 diabetes found 33.4% showed signs of undetected CVD, as indicated by elevated levels of 2 cardiac biomarkers, compared to only 16.1% of those without diabetes.
The analysis suggests that subclinical CVD was strongly associated with an increased risk of mortality in adults with T2D, even after adjustment for various demographic characteristics and cardiovascular risk factors, highlighting the need for greater prevention efforts.
“What we are seeing is that many people with T2D who have not had a heart attack or a history of CVD are at high risk for cardiovascular complications,” Elizabeth Selvin, PhD, MPH, a professor of epidemiology at Johns Hopkins Bloomberg School of Public Health said in a statement.2 “When we look at the whole population of people diagnosed with T2D, about 27 million adults in the US, according to the CDC, some are at low risk and some are at high risk for CVD, so the open question is ‘Who is most at risk?’ These cardiac biomarkers give us a window into cardiovascular risk in people who otherwise might not be recognized as highest risk.”
A 2022 consensus report from the American Diabetes Association recommended annual testing of biomarkers, including high-sensitivity cardiac troponin (hs-cTn) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) to enable early detection and prevention of heart failure. Prior evidence has suggested elevations in both cardiac biomarkers may confer substantial risk for major cardiac events and mortality in adults with diabetes. There is, however, a lack of national data and little is known regarding the burden and long-term consequences of subclinical CVD in adults with T2D in the general population.
The primary objective of the current analysis was to characterize the national prevalence of subclinical CVD, as assessed by elevated hs-cTnT and NT-proBNP, in adults in the US with and without diabetes. Participants were enrolled in the 1999 - 2004 National Health and Nutrition Examination Survey (NHANES). The population for the analysis included nonpregnant adults aged ≥20 years without self-reported CVD, and with valid measures of NT-proBNP, hs-cTnT, and covariates (n = 10,304).
Participants were 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). Investigators defined subclinical CVD as having either elevated hs-cTnT (≥14 ng/L) or NT-proBNP (≥125pg/mL) levels, measured using stored blood samples and determined mortality status through linkage to the National Death Index from baseline until December 2019.
From 1999 - 2004, 7% of US adults without a history of CVD had diabetes and were generally older, and had a higher burden of cardiovascular risk factors. Upon analysis, the findings showed 33.4% of adults with T2D had signs of subclinical CVD, compared to only 16.1% of individuals without diabetes. After age adjustment, elevated hs-CTnT, but not elevated NT-proBNP, was observed to be more common in people with diabetes, overall and across age, sex, race and ethnicity, and weight status.
Moreover, the prevalence of elevated hs-cTnT was significantly higher in individuals with longer diabetes duration and worse glycemic control. For those with diabetes, elevated hs-cTnT and NT-proBNP were independently associated with all-cause mortality (adjusted hazard ratio [aHR], 1.77; [95% CI, 1.33 - 2.34] and HR, 1.78 [95% CI, 1.26 - 2.51), and CVD mortality (aHR, 1.54 [95% CI, 0.83 - 2.85] and aHR, 2.46 [95% CI, 1.31 - 4.60]).
Based on these findings, the investigative team emphasized that screening for certain cardiac biomarkers should be added to the routine assessment of traditional cardiovascular risk factors.
“The biomarkers analyzed in this study are very powerful in systematically categorizing patients based on their health status,” Selvin said.2 “Measuring biomarkers more routinely may help us focus on cardiovascular prevention therapies for people with T2D who are at higher risk.”