Characteristics, treatment patterns, and outcomes of patients with transthyretin amyloidosis: a large-scale, observational, retrospective study in China (OverTTuRe China)

Background Evidence remains limited on disease journey for transthyretin (ATTR) amyloidosis in China. This study aims to analyse China data from OverTTuRe, an observational, retrospective, multi-country cohort study. Methods Data were extracted from medical records (2013–2024) at six leading hospitals in ATTR amyloidosis care across China. Eligible patients were adults with a confirmed ATTR amyloidosis diagnosis. Demographics/characteristics, treatment patterns, and clinical outcomes were analysed. Results Overall, 218 patients with ATTR amyloidosis were enrolled. Among them, 95.9% had a hereditary genotype (ATTRv), and 72.0% had a mixed phenotype (both cardiac and neurological involvement). In total, 72.5% were male, and 66.0% were classified as late onset (≥50 years). Ala97Ser was the most frequent variant (27.5%). Mean (SD) time from onset to diagnosis was 3.4 (4.0) years. The most common symptoms/signs at onset and diagnosis were numbness (27.9%) and lower extremity oedema (31.2%), respectively. After diagnosis, 58.3% initiated transthyretin stabilisers, a class of disease-modifying therapies, with a median time to initiation of 45.0 days (IQR, 2.0–202.0); 38.5% experienced ≥1 hospitalisation, with a median length of stay of 6.8 days (IQR, 2.4–13.2). Median (95% CI) time from diagnosis to new amyloidosis manifestation, all-cause hospitalisation, and all-cause mortality was 12.0 (9.7–15.8), 25.0 (18.4–35.1), and 84.0 (82.6–not estimable) months, respectively. Conclusions Chinese patients with ATTR amyloidosis demonstrated high clinical heterogeneity, delays in diagnosis and treatment initiation, poor disease outcomes, and considerable clinical burden. Trial registration NCT06355934, registered on 12 February 2024