Real-world impact of transitioning from one lipoprotein(a) assay to another in a clinical setting

Janeni Jeevanathan; Sigrid M Blom; Thomas Olsen; Kirsten B Holven; Erik K Arnesen; Torleif Trydal; Børge G Nordestgaard; Michael Sovershaev; Ying Chen; Kjetil Retterstøl; Jacob J Christensen

doi:10.1016/j.ajpc.2024.100726

Real-world impact of transitioning from one lipoprotein(a) assay to another in a clinical setting

Am J Prev Cardiol. 2024 Aug 25:19:100726. doi: 10.1016/j.ajpc.2024.100726. eCollection 2024 Sep.

Authors

Janeni Jeevanathan¹, Sigrid M Blom², Thomas Olsen¹, Kirsten B Holven^{1

3}, Erik K Arnesen¹, Torleif Trydal⁴, Børge G Nordestgaard^{5

6}, Michael Sovershaev⁷, Ying Chen^{7

8}, Kjetil Retterstøl^{1

9}, Jacob J Christensen¹

Affiliations

¹ Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, P.O. Box 1046 Blindern, 0317, Oslo, Norway.
² Novartis Norway AS, Nydalen alle 37, 0484, Oslo, Norway.
³ Norwegian National Advisory Unit on Familial Hypercholesterolemia, Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital Aker, P.O. Box 4959 Nydalen, 0424, Oslo, Norway.
⁴ Department of Clinical Research, Sørlandet Hospital, SSHF, P.O. Box 416 Lundsiden, 4604, Kristiansand, Norway.
⁵ The Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Borgmester Ib Juuls Vej 73, opgang 7, 2730, Herlev, Denmark.
⁶ Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N, Denmark.
⁷ Fürst Medical Laboratory, P. O. Box 158 Alnabru, 0614, Oslo, Norway.
⁸ Oslo Metropolitan University, P. O. Box 4, Norway.
⁹ The Lipid Clinic, Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital Aker, P. O. Box 4959 Nydalen, 0424, Oslo, Norway.

Abstract

Background and aims: Different lipoprotein(a) [Lp(a)] assays may affect risk stratification of individuals and thus clinical decision-making. We aimed to investigate how transitioning between Lp(a) assays at a large central laboratory affected the proportion of individuals with Lp(a) result above clinical thresholds.

Methods: We studied nationwide clinical laboratory data including 185,493 unique individuals (47.7 % women) aged 18-50 years with 272,463 Lp(a) measurements using Roche (2000-2009) and Siemens Lp(a) assay (2009-2019).

Results: While the majority of individuals (66-75 %) had low levels of Lp(a) (<30 mg/dL) independent of the assay used, the Roche assay detected 20 % more individuals with Lp(a) >50 mg/dL, 40 % more individuals with Lp(a) >100 mg/dL and 80 % more individuals with Lp(a) > 180 mg/dL than the currently used Siemens assay, likely due to calibration differences.

Conclusion: Transitioning from one Lp(a) immunoassay to another had significant impact on Lp(a) results, particularly in individuals approaching clinically relevant Lp(a) thresholds.

Keywords: Lipids; Lipoprotein(a); Lipoprotein(a) assay.