Baltimore, MD—Approximately one-third of adults with type 2 diabetes (T2D) might have undetected cardiovascular disease (CVD), based on elevated levels of two protein biomarkers that indicate heart damage, a new study has found. The bottom line for pharmacists is that those patients likely will require additional nonstatin-related therapies to lower the CVD risk associated with T2D.

The biomarkers were associated with undetected or symptomless CVD in adults with T2D compared with those without the condition, according to new research published in the Journal of the American Heart Association.

The Johns Hopkins Bloomberg School of Public Health–led researchers pointed out that tests for high-sensitivity cardiac troponin T (hs-cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) biomarkers are used to measure injury and stress to the heart. Mildly elevated concentrations of these proteins in the bloodstream may be an early warning sign of changes in the structure and function of the heart, they explained, which could increase the risk for future heart failure, coronary heart disease, or death.

“What we are seeing is that many people with type 2 diabetes who have not had a heart attack or a history of cardiovascular disease are at high risk for cardiovascular complications,” stated study coauthor Elizabeth Selvin, PhD, MPH, a professor of epidemiology at Johns Hopkins. “When we look at the whole population of people diagnosed with Type 2 diabetes, about 27 million adults in the U.S., according to the CDC, some are at low risk and some are at high risk for cardiovascular disease, 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.”

Accordingly, the researchers measured hs-cTnT and NT-proBNP in stored serum samples from the 1999 to 2004 National Health and Nutrition Examination Survey. Using samples from 10,304 U.S. adults without a history of CVD, the study team estimated the prevalence of elevated hs-cTnT (≥14 ng/L) and NT-proBNP (≥125 pg/mL) in those with and without diabetes. The associations between elevated hs-cTnT and NT-proBNP were examined with all-cause and CVD mortality after adjustment for demographics and traditional CVD risk factors. “The crude prevalence of subclinical CVD (elevated hs-cTnT or NT-proBNP) was approximately 2 times higher in adults with (versus without) diabetes (33.4% versus 16.1%),” the authors reported. “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 (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 HR 2.46; 95% CI, 1.31-4.60).”

Based on these findings, the researchers concluded that subclinical CVD affects about one in three adults with diabetes in the United States. Subclinical CVD also conferred a substantial risk of mortality, according to the study team, which added, “Routine testing of cardiac biomarkers may be useful for assessing and monitoring risk in persons with diabetes.”

Specific findings included the following:
• One-third (33.4%) of adults with T2D had signs of undetected CVD, as indicated by elevated levels of the two protein markers. That was in comparison with 16.1% of those without diabetes
• For adults with T2D, elevated levels of troponin and NT-proBNP were associated with 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 with normal levels of these proteins in the blood. The elevated risk remained after adjustment for other cardiovascular risk factors
• After adjustment for age, elevated levels of troponin were more common in persons with T2D overall and across categories of age, sex, race/ethnicity, and weight. On the other hand, NT-proBNP levels were not elevated in individuals with T2D compared with those without T2D when adjusted for age
• The prevalence of elevated troponin was significantly higher in persons who had T2D of longer duration and who were unable to control glucose levels

“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,” Dr. Selvin stated. “Our research suggests that additional non-statin-related therapies are needed to lower the cardiovascular disease risk in people with Type 2 diabetes.”

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.

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