Cor Vasa 2024, 66(5):481-486 | DOI: 10.33678/cor.2024.064

(Intra-individual variability of lipoprotein(a) and its potential impact on treatment decisions regarding this risk factor)

Tereza Nezbedová^a, Otto Mayer Jr.^{a, b}

^a II. interní klinika, Lékařská fakulta v Plzni, Univerzita Karlova a Fakultní nemocnice Plzeň, Plzeň, Česká republika

^b Biomedicínské centrum, Univerzita Karlova/Lékařská fakulta a Fakultní nemocnice, Plzeň, Česká republika

Introduction: Lipoprotein(a) represents a virtually overlooked risk factor for which targeted treatment may be available soon. It has been suggested that Lp(a) concentrations are stable over time and need to be mea- sured only once in a lifetime. We aimed to verify this in clinical practice.

Methods: The study includes 490 patients in whom Lp(a) was repeatedly collected, and we assessed its intra-individual variability.

Results: A total of 1657 individual Lp(a) determinations were performed, with a median of 3 examinations/patient and an interval between the first/last determination of 1.1 years. The mean coefficient of variability (CVi, ratio of the SD of all individual values and their mean) was 18.2%, the median intra-individual difference was 6.7 nmol/L (36.4%), while the highest observed difference was 228 nmol/L (86%). We also compared how many patients achieved 175 nmol/L (potential treatment cut-off), either by minimal or maximal individual value. If Lp(a) < 75 nmol/L, the factor variability would have no impact in this way. In patients with ≥ 125 nmol/L, treatment would be indicated by 57% using the lowest, while 88% using the highest individual value. In the "grey zone" of 75-125 nmol/L, only 15% of patients would be misclassified in this way.

Keywords: Biological variability, Indication criteria of treatment, Lp(a), Screening,

Received: July 21, 2024; Revised: July 21, 2024; Accepted: August 19, 2024; Prepublished online: June 2, 2012; Published: October 25, 2024  Show citation