A retrospective real-world study assessing diagnostic pattern of light-chain amyloidosis in Japan based on data from the medical data vision claims database

Background: Early diagnosis of primary or light chain (AL) amyloidosis is crucial for initiating appropriate therapeutic interventions. However, diagnosis is getting delayed (several months-to-years) in clinical practice. Objective: To investigate the real-world patterns of clinical procedures until initial diagnosis of AL amyloidosis in Japan. Design: Retrospective longitudinal, observational cohort study. Methods: This study included adults with AL amyloidosis using Medical Data Vision claims database (2003–2022). The primary endpoint was time from initial hospital visit until confirmed AL amyloidosis diagnosis. Symptoms, lab tests, and medical department visits until diagnosis, and mortality were analyzed. Results: Overall, 323 patients with AL amyloidosis were included (median age: 73.0 years). Median time to confirmed diagnosis was 81.5 days; reported longer in patients aged ⩾65 years versus <65 years, and Charlson Comorbidity Index ⩾4 than <4. Specific tests (tissue and bone marrow biopsy) were conducted 28–40 days close to the diagnosis. Patients visited internal medicine ( n = 158), hematology medicine ( n = 139), dermatology ( n = 97), and nephrology ( n = 93) departments for confirmed diagnosis. Time to confirmed diagnosis was shorter for patients who visited hematology (median: 7.5 days). Early diagnosed (⩽1 year) patients had longer time-to-in-hospital death than late diagnosis (>1 year). Conclusion: These real-world data from Japanese AL amyloidosis patients are crucial for early and effective treatment, leading to better prognosis.