Bioactive adrenomedullin for assessment of venous congestion in heart failure.

AIMS: Bioactive adrenomedullin (bio-ADM) is a vascular-derived peptide hormone that has emerged as a promising biomarker for assessment of congestion in decompensated heart failure (HF). We aimed to evaluate diagnostic and prognostic performance of bio-ADM for HF in comparison to amino-terminal pro-B-type natriuretic peptide (NT-proBNP), with decision thresholds derived from invasive haemodynamic and population-based studies. METHODS AND RESULTS: Normal reference ranges for bio-ADM were derived from a community-based cohort (n = 5060). Correlations with haemodynamic data were explored in a cohort of HF patients undergoing right heart catheterization (n = 346). Mortality and decision cutoffs for bio-ADM was explored in a cohort of patients presenting in the ER with acute dyspnoea (n = 1534), including patients with decompensated HF (n = 570). The normal reference range was 8-39 pg/mL. The area under the receiver operating characteristic curve (AUROC) for discrimination of elevated mean right atrial pressure (mRAP) and pulmonary arterial wedge pressure (PAWP) was 0.74 (95% CI = 0.67-0.79) and 0.70 (95% CI = 0.64-0.75), respectively, with optimal bio-ADM decision cutoff of 39 pg/mL, concordant with cubic spline analyses. NT-proBNP discriminated PAWP slightly better than mRAP (AUROC 0.73 [95% CI = 0.68-0.79] and 0.68 [95% CI = 0.61-0.75]). Bio-ADM correlated with (mRAP, r = 0.55) while NT-proBNP correlated with PAWP. Finally, a bio-ADM decision cutoff of 39 pg/mL associated with 30 and 90 day mortality and conferred a two-fold increased odds of HF diagnosis, independently from NT-proBNP. CONCLUSIONS: Bio-ADM tracks with mRAP and associates with measures of systemic congestion and with mortality in decompensated HF independently from NT-proBNP. Our findings support utility of bio-ADM as a biomarker of systemic venous congestion in HF and nominate a decision threshold.

Plasma Pro-Enkephalin A and Ischemic Stroke Risk: The Reasons for Geographic and Racial Differences in Stroke Cohort.

OBJECTIVES: The opioid neuropeptide pro-enkephalin A (PENK-A) may be a circulating marker of cardiovascular risk, with prior findings relevant to heart failure, kidney disease, and vascular dementia. Despite these findings, the association of PENK-A with ischemic stroke is unknown, so we examined this association in a prospective cohort study and analyzed differences by race and sex. MATERIALS AND METHODS: The REasons for Geographic and Racial Differences in Stroke study (REGARDS) is a prospective cohort study of 30,239 Black and White adults. Plasma PENK-A was measured in 473 participants that developed first-time ischemic stroke over 5.9 years and 899 randomly selected participants. Cox models adjusted for demographics and stroke risk factors were used to calculate hazard ratios (HRs) of stroke by baseline PENK-A. RESULTS: PENK-A was higher with increasing age, female sex, White race, lower body mass index, and antihypertensive medication use. Each SD higher increment of PENK-A was associated with an adjusted HR of 1.20 (95% CI 1.01-1.42) for stroke, with minimal confounding by stroke risk factors. Spline plots suggested a U-shaped relationship, particularly in White men, with an adjusted HR 3.88 (95% CI 1.94-7.77) for the 95th versus 50th percentile of PENK-A in White men. CONCLUSIONS: Higher baseline plasma PENK-A was independently associated with future stroke risk in REGARDS. This association was most apparent among White men. There was little confounding by established stroke risk factors, suggesting a possible causal role in stroke etiology. Further research is needed to understand the role of endogenous opioids in stroke pathogenesis.