Associations of mid-regional pro-adrenomedullin levels to cardiovascular and metabolic abnormalities, and mortality in an elderly population from the community

BackgroundThe mid-regional part of the prohormone of adrenomedullin (MR-proADM) is emerging as a novel risk indicator in patients with cardiac disease. We investigated MR-proADM levels and their changes over 5 years in elderly community-dwellers, together with the underlying cardiovascular and metabolic conditions, and the prognostic implications of these measurements.Methods and resultsMR-proADM was analyzed using a sandwich immunoassay (Thermo Fisher Scientific) in participants from the PIVUS study. Measurements were performed at 70 (n = 1002) and 75 years of age (n = 795) together with various measurements of other markers of cardiovascular function. In cross-sectional analyses, MR-proADM was independently related to current smoking, renal dysfunction, obesity, lower left-ventricular ejection fraction, and higher levels of N-terminal pro-B-type natriuretic peptide and C-reactive protein. There were no independent associations to other cardiovascular risk factors or vascular pathologies. MR-proADM levels predicted all-cause mortality during 8.0 years of follow-up independent of cardiovascular risk indicators (adjusted HR 5.1 [95% CI 2.8-9.5]; p < 0.001) using results obtained at 70 and 75 years as updated covariates. Baseline MR-proADM levels improved prognostic discrimination (IDI = 0.018 [p = 0.001]). Also the change in MR-proADM levels over time independently predicted all-cause mortality occurring after 75 years (adjusted HR 13.4 [95% CI 3.5-50.5]; p < 0.001).ConclusionsMR-proADM levels in the elderly integrate information on several relevant aspects in cardiovascular disease, namely cardiovascular risk factors including obesity, low-grade inflammation, renal dysfunction and left-ventricular abnormalities. Furthermore, MR-proADM and its changes over time predicted mortality, and might provide utility as an indicator of the overall cardiovascular risk burden.