Rationale and Design of the Canadian Lipoprotein(a) Registry.

Lipoprotein(a) [Lp(a)] is an independent, heritable risk factor for atherosclerotic cardiovascular disease. Guidelines recommend Lp(a) testing once in a lifetime and recognize it as a risk-enhancing factor. However, management of elevated Lp(a) in real-world clinical practice is not well described. Here we describe the rationale, design, and preliminary baseline characteristics of the Canadian Lp(a) Registry, a prospective, longitudinal observational study of patients with Lp(a) ≥ 100 nmol/L (≥ 50 mg/dL). Patient demographics, cardiovascular risk factors, laboratory results, and clinical outcomes are collected at baseline and at annual follow-up. The primary objective is to evaluate the clinical management and outcomes of patients with elevated Lp(a). From April 2024 to April 2025, 127 patients (mean age 57.5 ± 12.7 years, 48.8% female) were enrolled with a median Lp(a) level of 225 nmol/L (interquartile range 186-346 nmol/L), and 51.2% had multiple Lp(a) levels obtained. The most recent mean low-density lipoprotein cholesterol (LDL-C) was 2.49 ± 1.74 mmol/L. At the time of registry entry, 104 (81.9%) patients were receiving lipid-lowering therapies, including statins (74.8%), ezetimibe (48.0%), and proprotein convertase subtilisin/kexin type 9 inhibitors (27.6%), whereas 18.1% were not taking prescription lipid-lowering therapy. There were 66 (52.0%) patients with an LDL-C < 2.0 mmol/L. The Canadian Lp(a) Registry is an ongoing prospective, observational study designed to evaluate the clinical management, cardiovascular risk profile, and outcomes for patients with elevated Lp(a). It is expected to improve our understanding of how elevated Lp(a) is managed in contemporary clinical practice and to identify opportunities to improve care.