P-101: Burden of AL Amyloidosis and its Association with Cardiac Involvement: Initial Results from a Patient-Reported Outcome Survey

Introduction: Amyloid light chain (AL) amyloidosis is a rare, progressive, and often fatal disease in which misfolded light chains form soluble, toxic aggregates and deposit as amyloid in organs; these deposits can lead to damage, dysfunction, and failure. Among patients with AL amyloidosis, those with cardiac involvement are at the highest risk for early death. This study examines the burden of AL amyloidosis in recently diagnosed cardiac and non-cardiac patients.

Methods: Adults with AL amyloidosis diagnosed in the past 24 months were enrolled in a longitudinal, mixed-methods study. Patient-reported outcome (PRO) measures were used to assess disease burden, including the SF-36v2® Health Survey (SF-36v2), Kansas City Cardiomyopathy Questionnaire-12 Item Short Form (KCCQ-12), Work Productivity and Activity Impairment Questionnaire (WPAI), and a Patient Global Impression of Severity (PGI-S). Results are based on initial survey data collected in 2022-2023.

Participants were grouped by cardiac involvement (yes/no) and number of organs involved (1, 2, ≥3). Differences in PRO scores were tested using parametric or nonparametric tests based on score distributions.

Results: The analysis sample included 97 participants with a mean age of 59.4 years and greater proportions female (54.6%), White/Caucasian (86.6%), and based in the United States (74.2%). Mean time since diagnosis was 12.2 months and mean number of organs involved was 2 (range: 1-5). Almost all participants (92.8%) had received AL amyloidosis treatment prior to the initial survey. Cardiac involvement was reported by 57.7% of participants.

SF-36v2 and KCCQ-12 scores indicated impacts on health-related quality of life (HRQoL), especially on physical health and social functioning. Mean SF-36v2 domain and summary scores were all below the general population normative score of 50, exceeding established thresholds for meaningful impairment for all domains except Mental Health.

Participants with cardiac involvement had significantly (p < 0.05) worse mean SF-36v2 Physical Functioning scores (39.5 vs. 44.4, higher is better) and PGI-S scores (3.2 vs. 2.4, higher is worse) than those without cardiac involvement. Significant differences in the following scores were observed across groups defined by number of organs involved: SF-36v2 Physical Functioning, Role Physical, Social Functioning, and Physical Component Summary; KCCQ-12 Physical Limitations and Social Limitations; WPAI Activity Impairment; and PGI-S (p < 0.05). Participants with ≥3 organs involved experienced greater burden than those with fewer organs involved.

Conclusions: In this sample of participants with recently diagnosed AL amyloidosis, significant disease burden related to symptom severity and HRQoL impacts was observed. Participants with cardiac involvement and a greater number of organs involved experienced additional burden in these areas. Results demonstrate the need for better therapeutic options in these key clinical subgroups.