At Least 1 Out Of 3 Diabetic Patients Have Silent Heart Disease: What To Know

Coronary artery disease (CAD) is the number one killer of men and women. This is particularly true in patients with diabetes mellitus, a major risk for CAD. There is a long asymptomatic period for CAD when it is a silent disease so feeling good is not proof that there is no CAD.

According to the American Heart Association’s 2023 Statistical Update, 102,188 U.S. deaths in 2020 were attributed to diabetes (including Type 1 and Type 2 diabetes), and an estimated 1.64 million deaths globally.

There are different ways to identify "silent" CAD and one is with blood tests looking for the biochemical markers of CAD and whether they are present.

A new study characterized the burden and prognostic value of subclinical cardiovascular disease (CVD) assessed by cardiac biomarkers (blood tests) among adults with and without diabetes in the general US population.

Study and Results

The researchers measured two blood tests that are reliable markers of silent CAD. They were hs‐cTnT (high‐sensitivity cardiac troponin T) and NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide). The blood was from stored samples from the 1999 to 2004 National Health and Nutrition Examination Survey.

Among US adults without a history of CVD (n=10 304), we estimated the prevalence of elevated hs‐cTnT (≥14 ng/L) and NT‐proBNP (≥125 pg/mL) in those with and without diabetes. We examined the associations between elevated hs‐cTnT and NT‐proBNP with all‐cause and CAD mortality after adjustment for demographics and traditional CAD risk factors.

The prevalence of subclinical CAD (elevated hs‐cTnT or NT‐proBNP) was ≈2 times higher in adults with (versus without) diabetes (33% versus 16%).

After age adjustment, elevated hs‐cTnT, but not elevated NT‐proBNP, was more common in those with diabetes, overall and across age, sex, race and ethnicity, and weight status.

The prevalence of elevated hs‐cTnT was significantly higher in those with longer diabetes duration and worse glycemic control.

In persons with diabetes, elevated hs‐cTnT and NT‐proBNP were independently associated with all‐cause mortality and CAD mortality.

Among the adults with Type 2 diabetes, elevated levels of troponin and N-terminal pro-B-type natriuretic peptide were associated with an increased risk of all-cause death (77% and 78% increased risk, respectively) and cardiovascular death (54% and more than double the increased risk, respectively), compared to normal levels of these proteins in the blood. This elevated risk remained after adjusting for other cardiovascular risk factors

Conclusions

Subclinical CAD measured by two blood tests affects ≈1 in 3 US adults with diabetes and confers substantial risk for mortality. Routine testing of cardiac biomarkers may be useful for assessing and monitoring risk in persons with diabetes.

One of the authors commented that “Cholesterol is often the factor that we target to reduce the risk of cardiovascular disease in people with Type 2 diabetes. However, Type 2 diabetes may have a direct effect on the heart not related to cholesterol levels. If Type 2 diabetes is directly causing damage to the small vessels in the heart unrelated to cholesterol plaque buildup, then cholesterol-lowering medications are not going to prevent cardiac damage. Our research suggests that additional non-statin-related therapies are needed to lower the cardiovascular disease risk in people with Type 2 diabetes.”

At the Kahn Center, all patients are tested for these two blood tests. In addition, all patients have some form of CT heart artery imaging (calcium score or angiography) and also carotid IMT artery imaging with ultrasound. High-risk patients are identified and treated intensively with lifestyle, supplements, and Rx medications.