Clinical Researcher Providence Health Care Vancouver, British Columbia, Canada
Background: The Canadian Registry for Amyloidosis Research (CRAR) is a national registry. Advances in disease-modifying medical therapy have improved prognosis, however there is a critical need for real-world evidence to address knowledge gaps, particularly longer-term therapeutic outcomes and surveillance strategies. The objective of this analysis is to report baseline demographic, clinical, biochemical and imaging data from a Canadian amyloidosis patient cohort.
METHODS AND RESULTS: CRAR is active at 7 academic centres across 5 provinces of Canada. Data is collected from specialty clinics in cardiology, hematology, and neurology and abstracted by trained coordinators. Clinic-reported data on disease onset, progression, severity, treatments, and outcomes along with patient-reported outcomes are collected. Both prospective and retrospective (including deceased) patient cohorts are included.
Presently, 520 participants are enrolled with complete baseline data. Of those, 350 (67%) are ATTR, 122 (23%) AL, 41 (9%) undifferentiated and 7 (1%) other. Patients were 79% (n=408) male, mean age at diagnosis was 74 years, with an average of 26 months between symptom onset to diagnosis. There are presently 135 (26%) deceased patients in CRAR; cause of death was cardiac for 42 (34%), non-cardiac in 18 (13%), and unknown for 75 (56%). For TTR, 20% of patients were reported to have been diagnosed by biopsy while 75% were diagnosed by nuclear scintigraphy. Among ATTR patients, 45 (15%) had hereditary subtype, with V50M (19, 42%) and V142I (13, 29%) the most common. Among ATTR, 138 (39%) were NAC stage 1, 76 (22%) stage 2, and 36 (10%) stage 3 at baseline. Table 1 presents baseline characteristics stratified by subtype. At baseline, 73 (21%) had NYHA functional class I heart failure, 146 (42%) class II, 73 (21%) class III, and 7 (2%) class IV. Mean troponin-T was 68 ng/L (0-870), NTproBNP 4321 ng/L (34-70000), and left ventricular ejection fraction 52% (12-77). There were 62 (12%) patients with an implantable cardiac device and 43 (8%) with aortic stenosis. There were 139 (40%) ATTR and 73 (60%) AL patients recorded on disease-modifying therapy (DMT) at initial baseline visit, while 271 (52%) reported no DMT.
Conclusion: CRAR collects a prospective and retrospective, longitudinal, multidisciplinary data to characterize the Canadian amyloidosis patient population, including DMT and outcomes, and continues to expand into academic and community centers. This initial report describes baseline characteristics.
