Optimal carbohydrate antigen 125 cutpoint for identifying low-risk patients after admission for acute heart failure.

Introduction And Objectives: Carbohydrate antigen 125 (CA125) has been shown to be useful for risk stratification in patients admitted with acute heart failure (AHF). We sought to determine a CA125 cutpoint for identifying patients at low risk of 1-month death or the composite of death/HF readmission following admission for AHF.

Methods: The derivation cohort included 3231 consecutive patients with AHF. CA125 cutoff values with 90% negative predictive value (NPV) and sensitivity up to 85% were identified. The adequacy of these cutpoints and the risk of 1-month death/HF readmission was then tested using the Royston-Parmar method. The best cutpoint was selected and externally validated in a cohort of patients hospitalized from BIOSTAT-CHF (n=1583).

Results: In the derivation cohort, the median [IQR] CA125 was 57 [25.3-157] U/mL. The optimal cutoff value was <23 U/mL (21.5% of patients), with NPVs of 99.3% and 94.1% for death and the composite endpoint, respectively. On multivariate survival analyses, CA125 <23 U/mL was independently associated with a lower risk of death (HR, 0.20; 95%CI, 0.08-0.50; P <.001), and the combined endpoint (HR, 0.63; 95%CI, 950.45-0.90; P=.009). The ability of this cutpoint to discriminate patients at a low 1-month risk was confirmed in the validation cohort (NPVs of 98.6% and 96.6% for death and the composite endpoint). The predicted ability of this cutoff remained significant at 6 months of follow-up.

Conclusions: In patients admitted with AHF, CA125 <23 U/mL identified a subgroup at low risk of short-term adverse events, a population that may not require intense postdischarge monitoring.