Distribution and variation of lipoprotein(a) in patients attending a lipid clinic in Greece

Background and Aims: To investigate the distribution and variation of lipoprotein(a) [Lp(a)] in patients with dyslipidemia attending a lipid clinic in Greece. Methods: Retrospective observational study of patients with dyslipidemia attending a tertiary lipid clinic in Greece. Electronic health records were scrutinized for patients with available Lp(a) measurements from 2012 to 2022. Lp(a) variation was investigated in those having ≥2 heterochronized Lp(a) measurements during follow-up and were on stable hypolipidemic treatment. Results: 1975 patients were included (51.3% females, 98% adults, median age 49 years [IQR: 37-60]). Median Lp(a) was 10.7 mg/dL (IQR: 4.4-27.8); values at 80th, 90th, and 95th percentiles were 35.9, 59.9 and 84.3 mg/dL, respectively. Οf patients, 13.9% had Lp(a) ≥50 mg/dL. 775 patients had their Lp(a) measured twice during follow-up (0.6 [0.3-1.7] years). Lp(a) medians at 1st and 2nd visit were similar (13.5 [5.6-39] and 13.6 [5.6-39] mg/dL, p>0.05). Median intra-individual variation of Lp(a) was 13% (5-23%). As shown in Figure, 32% of patients were reclassified to a higher Lp(a) group and 28% to a lower Lp(a) group during follow-up. Higher Lp(a) variation was observed in children compared to adults (20% [13-26] vs 13% [6-24], p>0.05). Highest quartile of follow-up (>1.69 years) was associated with higher Lp(a) variation compared to the 1st quartile (15% [8-28] vs 11% [5- 23], p<0.05). Conclusions: Prevalence of Lp(a) >50 mg/dL in patients attending a lipid clinic in Greece is 13.9%. One in 4 patients showed a variation in Lp(a) over 20% during their follow-up. Childhood and duration of follow-up seem to be associated with increased Lp(a) variation.