Carbohydrate Antigen 125 Serial Measurements after an Admission for Acute Heart Failure and Risk of Early Readmission

Fundament and objectives: The early readmission after a hospitalization for acute heart failure (AHF) is frequent; however, factors associated are not clearly established. Plasma levels of carbohydrate antigen 125 (CA125) have shown to be associated with the presence of systemic congestion and increased risk of death in patients with AHF. The aim of this study was to assess the relationship between CA125 levels (during hospitalization, at the first outpatient visit or their changes) and readmission for AHF at 6 months follow up. Patients and method: We analyzed 293 consecutive patients hospitalized for AHF in which CA125 was determined during the index hospitalization (T1) and the first outpatient visit after discharge (12) (median 31 days). We examined the relationship between CA125 levels, both isolated determinations as their serial changes (absolute, relative or categorical) and readmission for AHF by Cox regression analysis adjusted for competing events. The reclassification technique integrated discrimination improvement (IDI) index was used to assess the additional discriminative power of this biomarker over the final multivariate model. Results: At 6 months follow up, we identified 32(10.9%) and 54(18.4%) deaths and readmissions for AHF, respectively. CA125 categorical changes [decrease and normalization (C1, n=153), decrease but no normalization at 12 (C2, n=72) and increase, with high levels at 12 (>35 U/ml) (C3, n=68)], followed by the isolated determination of CA125 at 12, showed the best discriminative accuracy. Thus, with respect to patients in the Cl category, patients in categories C2 and C3 showed a higher risk of readmission for AHF: C2 vs. C1:HR=3.48, 95% CI:1.84-6.59, p<0.001; C3 vs. C1:HR=3.18, 95% CI:1.62-6.21, p=0.001. On the other hand, patients with elevated levels of CA125 in T2 (>35 U/ml) (41%) tripled the risk of readmission for AHF at 6 months compared with those with normal levels of CA125 at 12: HR=3.06, 95% CI: 1.79-5.23, p<0.001. The addition of the categories of serial measurements of CA125 and the presence of elevated levels of CA125 at T2 showed a significant increase in the discriminating power of 6.27% and 6.17% in the IDI index, respectively. Conclusions: After an episode of AHF, the elevation of CA125 levels (>35 U/ml) after the first weeks of admission is associated with an increased risk of readmission for AHF. (C) 2011 Elsevier Espana, S.L. All rights reserved.