Response to Letter to the Editor regarding “Lipoprotein(a) and clinical characteristics of Polish patients hospitalized in a tertiary referral hospital — an observational, cross-sectional study”

To the Editor,

We read with great interest the Letter to the Editor [1] concerning our study on lipoprotein(a) [Lp(a)] and clinical characteristics of Polish patients hospitalized in a tertiary referral hospital [2]. We thank the Authors for their interest in our research and valuable comments along with the suggestions for further continuation of this project.

First, we agree that the relatively small sample size is an important limitation that implicates insufficient statistical power to detect some differences between the groups. We plan to further continue this project with a larger sample size to increase the reliability of our results.

Further, the fact that the mean low-density lipoprotein (LDL) cholesterol was slightly higher in the group with elevated Lp(a), whereas the mean non-high-density lipoprotein (non-HDL) cholesterol was paradoxically lower merits attention. Beyond Lp(a) and LDL-cholesterol, other lipid components contribute to non-HDL-cholesterol, including very low-density lipoprotein (VLDL) cholesterol, intermediate-density lipoprotein (IDL) cholesterol and chylomicron remnants. Since these components are affected by numerous factors including genetics, diet, lifestyle and fasting status, these other components might have contributed to the paradoxically lower mean non-HDL-cholesterol in the group with elevated Lp(a). The lipid panel was performed using the standardized hospital Abott Alinity C analyzer, and the Lp(a) measurements were performed using the Roche cobas c 503 according to the standardized protocol, which ensured the reliability of the lipid profile data. Altogether, we fully agree that this interesting observation deserves further discussion and potentially more detailed analysis in future work.

To conclude, we appreciate the Letter to the Editor regarding our recent publication and hope that the ongoing scientific discussion will increase awareness of the importance of Lp(a) in routine clinical practice.