The Role of Adrenomedullin as a Predictive Marker of the Risk of Death and Adverse Clinical Events: A Review of the Literature

Adrenomedullin (ADM) is a vasodilatory peptide that plays a crucial role in maintaining cardiovascular health through its various biological functions. ADM was discovered in the acidic extract of human pheochromocytoma tissue and has been recognized for its significant effects on the vascular system. The main functions of ADM include vasodilation, controlling blood pressure and maintaining vascular integrity, although its role on cardiovascular health is broader. Research has shown that elevated levels of adrenomedullin have been observed in a large number of severe diseases, with high risk of death. In this work, we examined the role of ADM as a predictive molecule of the risk of mortality and adverse clinical outcome through a narrative review of the scientific literature. The results were divided based on the pathologies and anatomical districts examined. This review demonstrates how ADM shows, in many diseases and different systems, a close correlation with the risk of mortality. These results prove the value of ADM as a prognostic marker in various clinical contexts and diseases, with utility in the stratification of the risk of clinical worsening and/or death and in the evaluation of therapeutic efficacy. The results open new perspectives with respect to the concrete possibility that ADM enters clinical practice as an effective diagnostic and prognostic marker of death as well as a molecular target for therapies aimed at patient survival.

Postoperative bioactive adrenomedullin is associated with the onset of ARDS and adverse outcomes in patients undergoing open thoracoabdominal aortic surgery

Cytokine-mediated systemic inflammation after open thoracoabdominal aortic aneurysm (TAAA) repairs plays a pivotal role in disrupting circulatory homeostasis, potentially leading to organ dysfunction. The bioactive form of adrenomedullin (bio-ADM) is a peptide hormone with immunomodulatory and vasomotor effects, making it a potential diagnostic agent in these cases. This retrospective, bicentric study, conducted between January 2019 and December 2022, recruited 36 elective open TAAA repair patients in two German centres. Serum and plasma samples were collected at multiple time points to measure bio-ADM levels. The primary objective was to evaluate the association of bio-ADM levels with the onset of acute respiratory distress syndrome (ARDS), with secondary endpoints focusing on mortality and SIRS-related morbidity. Results showed a significant association between postoperative bio-ADM levels (12-48 h after surgery) and the onset of ARDS (p < .001), prolonged ventilation (p = .015 at 12h after surgery), atrial fibrillation (p < .001), and mortality (p = .05 at 24h). The biomarker was also strongly associated with sepsis (p = .01 at 12 h) and multi-organ dysfunction syndrome (MODS) (p = .02 at 24 h after surgery). The study underscores the potential utility of bio-ADM as a diagnostic tool for identifying patients at risk of postoperative complications following open TAAA repairs.

The NephroCheck bedside system for detecting stage 3 acute kidney injury after open thoracoabdominal aortic repair

Acute kidney injury (AKI) is a common complication after complex aortic procedures and it is associated with relevant mortality and morbidity. Biomarkers for early and specific AKI detection are lacking. The aim of this work is to investigate the reliability of the NephroCheck bedside system for diagnosing stage 3 AKI following open aortic surgery. In this prospective, multicenter, observational study,- https://clinicaltrials.gov/ct2/show/NCT04087161 -we included 45 patients undergoing open thoracoabdominal aortic repair. AKI risk (AKIRisk-Index) was calculated from urine samples at 5 timepoints: baseline, immediately postoperatively and at 12, 24, 48, and 72 h post-surgery. AKIs were classified according to the KDIGO criteria. Contributing factors were identified in univariable and multivariable logistic regression. Predictive ability was assessed with the area under the receiver operator curve (ROCAUC). Among 31 patients (68.8%) that developed AKIs, 21 (44.9%) developed stage-3 AKIs, which required dialysis. AKIs were correlated with increased in-hospital mortality (p = .006), respiratory complications (p < .001), sepsis (p < .001), and multi-organ dysfunction syndrome (p < .001). The AKIRisk-Index showed reliable diagnostic accuracy starting at 24 h post-surgery (ROCAUC: .8056, p = .001). In conclusion, starting at 24 h after open aortic repair, the NephroCheck system showed adequate diagnostic accuracy for detecting the patients at risk for stage 3 AKIs.

Levels of bioactive adrenomedullin in plasma and cerebrospinal fluid in relation to delayed cerebral ischemia in patients after aneurysmal subarachnoid hemorrhage: A prospective observational study

OBJECTIVES

Adrenomedullin (ADM) has been identified as a promising biomarker of mortality and outcome in sepsis, heart failure and after major surgery. A recently developed assay specific for bioactive adrenomedullin (bio-ADM) has not yet been assessed in aneurysmal subarachnoid hemorrhage (aSAH). The objective of this prospective trial was to assess the time course of bio-ADM after aSAH in relation to the development of delayed cerebral ischemia (DCI) and its association with clinical outcome.

METHODS

Bio-ADM levels in plasma and cerebrospinal fluid (CSF) were measured during five predefined epochs, for up to 21 days in 30 aSAH patients: early, (day 0 to day 3); acute, (day 4 to day 8); early critical, (day 9 to day 12); late critical, (day 13 to day 15), and late (day 16 to day 21). DCI was diagnosed clinically or based on multimodal monitoring and imaging, and the occurrence of DCI-related cerebral infarction, and outcome after 12 months (extended Glasgow outcome scale), was noted.

RESULTS

Higher median bio-ADM levels in plasma during the acute phase were predictive of long-term unfavorable outcome (AUC = 0.97; 95% CI 0.91 to 1.00; p < 0.001). Early critical bio-ADM levels during DCI were lower in CSF and confirmed DCI occurrence (AUC = 0.80; 95% CI 0.59 to 1.00; p = 0.044).

CONCLUSION

The dynamics of bio-ADM levels in CSF present a fairly different course compared to plasma with observed higher bio-ADM concentrations in patients spared from DCI and/or developing favorable outcome.

In-hospital mortality and organ failure after open and endovascular thoraco-abdominal aortic surgery can be predicted by increased levels of circulating dipeptidyl peptidase 3

OBJECTIVES

Endovascular and open thoraco-abdominal aortic aneurysm (TAAA) repair is associated with specific complications. Circulating dipeptidyl peptidase 3 (cDPP3) is a novel biomarker that shows a strong association with organ failure which has not been assessed in surgical settings. Therefore, the objective of this study was to assess the prognostic capabilities of cDPP3 for predicting patient survival and organ failure following open and endovascular TAAA repair.

METHODS

Thirty-three patients undergoing TAAA repair were assessed in this prospective observational single-centre study. cDPP3 levels were serially measured perioperatively until 72 h after admission to the intensive care unit (ICU). In-hospital mortality and any organ failure were the clinical end points.

RESULTS

Postoperative organ failure was detected in 17 patients (51.5%), and 6 patients died after surgery (18.2%). At 12 h after admission to the ICU, cDPP3 levels were significantly increased in patients who died or developed organ failure (P < 0.001). cDPP3 levels after surgery demonstrated a remarkable predictive accuracy for in-hospital mortality [12 h area under the receiver operating characteristic curve (AUC): 0.907 (P < 0.001), 24 h AUC: 0.815 (P = 0.016), 48 h AUC: 0.914 (P = 0.003)] and the development of organ failure [12 h AUC: 0.882 (P < 0.001), 24 h AUC: 0.850 (P < 0.001), 48 h AUC: 0.846 (P < 0.001)]. Additionally, a significant correlation between cDPP3, the sequential organ failure assessment score and procalcitonin, C-reactive protein and interleukin-6 levels (P < 0.001, P < 0.001, P = 0.011, P = 0.007, respectively) based on all available measurements and time points was observed.

CONCLUSIONS

The present findings highlight the role of cDPP3 as an early, highly specific postoperative biomarker for prediction of in-hospital mortality and organ failure after TAAA repair.