Özben Özden IŞIKLAR, Cansu MANAV, Evin KOCATÜRK, Hüseyin KAYADİBİ, İbrahim Özkan ALATAŞ
Journal of Turkish Clinical Biochemistry - 2026;24(1):7-11
Objective: This study aimed to evaluate the frequency of repeat lipoprotein(a) testing, determine whether repeated measurements changed risk classification, assess the clinical significance of observed changes using the reference change value, and investigate whether the interval between measurements was associated with the magnitude of change. Methods: In this single-center, retrospective, observational study, laboratory records of 706 patients who had at least one lipoprotein(a) measurement between 01.12.2024 and 01.12.2025 at a tertiary care university hospital were reviewed. In patients with repeated measurements, the first and last results were compared, changes in risk classification were evaluated, and clinical significance was assessed using the reference change value. Results: Among 706 patients, 148 (21.0%) had repeated measurements. In this subgroup, the last lipoprotein(a) level was significantly lower than the first measurement. However, 92.6% of patients remained in the same risk category, while 6.8% were reclassified to a lower risk category and 0.7% to a higher risk category. The proportions of patients remaining in the same category were 99.0%, 68.8%, and 82.1% in the low-, intermediate-, and high-risk groups, respectively. In 106 paired measurements eligible for percentage-change analysis, a significant positive relationship was found between the interval between measurements and absolute percentage change. However, no patient exceeded the calculated reference change value of 58.7%. Conclusion: Repeat lipoprotein(a) testing is uncommon in routine clinical practice. Since it does not provide clinically meaningful additional information in most patients, a single measurement appears to be sufficient for most individuals. Repeat testing may be considered only in selected patients with values close to clinical decision thresholds.
