Incidence and prevalence of light chain amyloidosis in the United States in 2019-2021 using Optum EHR data.

Immunoglobulin light chain amyloidosis (AL amyloidosis) is among the most common forms of systemic amyloidosis. Using electronic health records (EHR) data from the United States, we aimed to estimate the incidence and prevalence of AL amyloidosis over time, to evaluate the distribution of different disease stages, and to assess patients' demographic characteristics. We conducted a retrospective cohort study using Optum EHR data from 2016 to 2022. AL amyloidosis was defined by ≥ 2 ICD-10-CM codes or positive mentions in the EHR that were ≥ 30 days apart. Incident and prevalent patients were included. Staging was assessed using cardiac biomarkers (whenever available) according to the European modification of the 2004 Mayo staging system. A total of 1976 AL amyloidosis patients were identified. In 2021, the estimated AL amyloidosis incidence was 16.7 per million person-years in adults, and the prevalence was 69.0 per million adult population. Among patients with staging available near the time of diagnosis (41.7% of incident patients), the following distribution was observed: 16.1% Stage I, 44.5% Stage II, 20.6% Stage IIIa, and 18.8% Stage IIIb. At the most recently available staging assessment, combined Stage IIIa and IIIb was more common among males (38.6% vs. 27.1%) and was more common with increasing age (25.7% for 40-49 years vs. 38.5% for 80+ years). We observed the highest prevalence of AL amyloidosis published to date. This may be due to true increased prevalence, consistent with reports of improved survival in AL amyloidosis.