Prediction of Medium-Term Mortality in Japanese Patients With Wild-Type Transthyretin Amyloidosis

Background: The prognostic factors in Japanese patients with wild-type transthyretin amyloidosis (ATTRwt) have not been elucidated. Methods and Results: In this study we retrospectively analyzed the clinical characteristics and outcomes of 47 patients with ATTRwt (mean (±SD) age at diagnosis 80.3±4.6 years; 41 males). Fifteen patients died within 2 years of their diagnosis. Receiver operating characteristic and Kaplan-Meier analyses revealed that the best predictors of 2-year mortality were low serum albumin (≤3.75 g/dL), elevated high-sensitivity cardiac troponin T (hs-cTnT; >0.086 ng/mL), and reduced left ventricular ejection fraction (LVEF; <50%). According to the total number of these 3 risk factors, patients were stratified into 4 subgroups: low risk (no risk factors; n=15), intermediate-low risk (1 risk factor; n=15), intermediate-high risk (2 risk factors; n=7), and high risk (3 risk factors; n=10). The estimated 2-year survival rate of patients classified as low risk, intermediate-low risk, intermediate-high risk, and high risk was 93%, 80%, 83%, and 11%, respectively (P<0.001). Conclusions: Low serum albumin, elevated hs-cTnT, and reduced LVEF are associated with a worse prognosis in Japanese patients with ATTRwt. The combination of these factors may be useful for predicting medium-term mortality in patients with ATTRwt.