Temporal Trends and Outcomes of Amyloidosis in Korea: A 14-Year Nationwide Cohort Study.

Background/Objectives: The diagnostic and therapeutic landscape of amyloidosis has evolved significantly with the introduction of non-invasive imaging and novel agents. However, contemporary real-world data reflecting these recent changes-particularly regarding the burden and prognostic impact of cardiac involvement-remain limited. We aimed to evaluate up-to-date temporal trends in the incidence, prevalence, and outcomes of amyloidosis using a nationwide cohort spanning the recent era. Methods: Using the Korean National Health Insurance Service database, we identified 5165 patients with newly diagnosed amyloidosis. Cardiac amyloidosis was defined by the presence of heart failure, cardiomyopathy, atrial fibrillation, or pacemaker implantation. Propensity score matching was performed to compare mortality risks between patients with and without cardiac involvement. Temporal trends in outcomes were analyzed across three periods (2009-2013, 2014-2018, and 2019-2022). Results: The incidence and prevalence of amyloidosis steadily increased, with a marked rise observed after 2019. Cardiac involvement was identified in 44.6% of patients and was associated with significantly higher risks of all-cause death (hazard ratio [HR] 1.396; 95% CI 1.214-1.606) and cardiovascular death (HR 1.879; 95% CI 1.254-2.816) in the matched cohort. Notably, while all-cause mortality gradually declined over the study period, cardiovascular mortality showed no significant improvement, remaining persistently high even in the most recent cohort. Conclusions: In this contemporary nationwide cohort, the burden of amyloidosis has grown over the past decade. Despite improvements in overall survival, the persistent risk of cardiovascular mortality highlights a critical unmet need for targeted cardiovascular management in this population.