Adrenomedullin optimises mortality prediction in COPD patients

Background: Current multicomponent scores that predict mortality in COPD patients might underestimate the systemic component of COPD. Therefore, we evaluated the accuracy of circulating levels of proadrenomedullin (MR-proADM) alone or combined with the ADO (Age, Dyspnoea, airflow Obstruction), updated ADO or BOD (Body mass index, airflow Obstruction, Dyspnoea) index to predict all-cause mortality in stable COPD patients. Methods: This study pooled data of 1285 patients from the COMIC and PROMISE-COPD study. Results: Patients with high MR-proADM levels ( 0.87 nmol/l) had a 2.1 fold higher risk of dying than those with lower levels (p < 0.001). Based on the C-statistic, the ADOA index (ADO plus MR-proADM) (C Z 0.72) was the most accurate predictor followed by the BODA (BOD plus MR-proADM) (C Z 0.71) and the updated ADOA index (updated ADO plus MRproADM) (C Z 0.70). Adding MR-proADM to ADO and BOD was superior in forecasting 1- and 2-year mortality. The net percentages of persons with events correctly reclassified (NRIþ) within respectively 1-year and 2-year was 31% and 20% for ADO, 31% and 20% for updated ADO and 25% and 19% for BOD. The net percentages of persons without events correctly reclassified (NRI-) within respectively 1-year and 2-year was 26% and 27% for ADO, 27% and 28% for updated ADO and 34% and 34% for BOD. Conclusions: Adding MR-proADM increased the predictive power of BOD, ADO and updated ADO index.