Incidence rate of hospitalization and mortality in the first year following initial diagnosis of cardiac amyloidosis in the US claims databases

Objective: This study aimed to determine rates of hospitalization and in-hospital mortality in the first year following amyloidosis diagnosis with cardiac involvement using observational databases.

Methods: Three administrative claims databases, IBM MarketScan^® Commercial Claims and Encounters (CCAE), IBM MarketScan^® Multi-State Medicare Database (MDCR), and Optum's de-identified Clinformatics^® Data Mart Database (Optum) were analyzed. Adults ≥18 years old, with a diagnosis of amyloidosis and evidence of cardiac involvement (i.e. heart failure, heart block, or cardiomyopathy) but no hepatic/renal failure prior to amyloidosis diagnosis were included for analysis. The primary analyses identified patients between 01-01-2010 and 31-12-2017 period. We calculated the rates of hospitalization and in-hospital mortality within 1 year after the initial diagnosis of amyloidosis. A sensitivity analysis was conducted for patients identified in Optum database during 2004-2011 period, which provided additional mortality information.

Results: A total of 419, 654, and 922 patients from CCAE, MDCR, and Optum were identified during 2010-2017 period, with mean age of 55.6, 77.8, and 74.2 years, respectively. Within 1 year following initial amyloidosis diagnosis, incidence rates (95% confidence interval [CI]) of hospitalization were 78.4 (66.3, 90.4), 78.6 (69.2, 87.9), and 61.2 (54.4, 68.0) per 100 person-years, rates of in-hospital mortality were 16.5 (11.8, 21.3), 8.4 (5.7, 11.0), and 17.7 (14.5, 21.0) per 100 person-years, in CCAE, MDCR, and Optum, respectively. The mortality rate from the sensitivity analysis among patients identified in Optum 2004-2011 period was higher compared with Optum 2010-2017 period.

Conclusions: The results from this study indicate that amyloidosis with cardiac involvement is a condition with high rates of hospitalization and mortality in the first year after initial diagnosis. Future studies are needed to further evaluate the outcomes within the subtypes of amyloidosis and understand the risk factors associated with poor prognoses.