The biological role of adrenomedullin, a hormone involved in hemodynamic homeostasis, is controversial in sepsis, since administration of either the peptide or an antibody against it may be beneficial.
Plasma bio-ADM was assessed on days 1, 2 and 7 after randomization of 956 patients with sepsis or septic shock to albumin or crystalloids for fluid resuscitation in the multicenter Albumin Italian Outcome Sepsis (ALBIOS) trial. We tested the association of bio-ADM and its time-dependent variation with fluid therapy, vasopressor administration, organ failures and mortality.
Plasma bio-ADM on day 1 (median[Q1-Q3], 110[59-198] pg/mL) was higher in patients with septic shock, associated with 90-day mortality, multiple organ failures and the average extent of hemodynamic support therapy (fluids and vasopressors) and serum lactate time-course over the first week. Moreover, it predicted incident cardiovascular dysfunction in patients without shock at enrollment (OR [95% CI] 1.9 [1.4-2.5], p<0.0001, for an increase of 1 interquartile range of bio-ADM concentration). Bio-ADM trajectory during the first week of treatment clearly predicted 90-day mortality, after adjustment for clinically relevant covariates (HR [95% CI] 1.3 [1.2-1.4], p<0.0001), and its reduction below 110 pg/mL at day 7 was associated to a marked reduction in 90-day mortality. Changes over the first 7 days of bio-ADM concentrations were not dependent on albumin treatment.
In patients with sepsis, the circulating, biologically active form of adrenomedullin may help individualizing hemodynamic support therapy, while avoiding harmful effects. Its possible pathophysiologic role makes bio-ADM a potential candidate for future targeted therapies.