Abstract
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.