Cardiovascular Diabetology (Aug 2024)
N-terminal pro-B-type natriuretic peptide levels vary by ethnicity and are associated with insulin sensitivity after gestational diabetes mellitus
Abstract
Abstract Background Individuals of South Asian origin have a greater risk of cardiovascular disease after gestational diabetes mellitus (GDM) than European individuals. B-type natriuretic peptide (BNP) and the amino-terminal fragment of its prohormone (NT-proBNP) are commonly used for heart failure screening and diagnosis, but biologically BNP exerts several beneficial cardiovascular effects primarily by counteracting the renin-angiotensin-aldosterone-system. We asked whether ethnic differences in circulating NT-proBNP levels could be explained by the differences in cardiometabolic and inflammatory risk markers? Methods We examined 162 South Asian and 107 Nordic women in Norway 1–3 years after GDM with a clinical examination, fasting blood samples and an oral glucose tolerance test. We measured the levels of NT-proBNP, high-sensitivity cardiac troponin T, high-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), leptin, adiponectin and markers of insulin sensitivity, such as the Matsuda insulin sensitivity index (ISI). Finally, we tried to identify which independent covariate best mediated the ethnic differences in NT-proBNP. Results The mean (SD) age was 35.3 (4.5) years, BMI 29.1 (6.0) kg/m2, waist-height ratio 0.60 (0.08) and 164 women (61%) had prediabetes/diabetes. Notably, South Asian women had lower levels of NT-proBNP than Nordic women in both the normoglycemic and prediabetes/diabetes groups (median (IQR) 26 (15–38) vs. 42 (22–66) ng/L, p < 0.001). Higher NT-proBNP levels were associated with greater insulin sensitivity in both South Asian and Nordic women (p = 0.005 and p < 0.001). South Asian women had higher levels of hsCRP (median (IQR) 2.2 (1.1–4.4) vs. 1.2 (0.3–4.2) mg/L), IL-6 (2.3 (1.5–3.2) vs. 1.5 (1.5–2.5) pg/mL), leptin (1647 (1176–2480) vs. 1223 (876–2313) pmol/L), and lower adiponectin levels (7.2 (5.3–9.3) vs. 10.0 (7.2–13.5) mg/L) and Matsuda ISI (2.4 (1.7–3.7) vs. 4.2 (2.9–6.1), pall<0.01) than Nordic women. Even after adjusting for these differences, higher NT-proBNP levels remained associated with insulin sensitivity (22% higher NT-proBNP per SD Matsuda ISI, p = 0.015). Insulin sensitivity and adiponectin mediated 53% and 41% of the ethnic difference in NT-proBNP. Conclusions NT-proBNP levels are lower in South Asian than in Nordic women after GDM. Lower NT-proBNP levels correlate with impaired insulin sensitivity. Lower NT-proBNP levels in South Asian women could, therefore, be attributed to impaired insulin sensitivity rather than total body fat.
Keywords