Abstract
Background
Familial hypercholesterolemia (FH) is a genetic disorder caused by mutations in genes involved in low-density lipoprotein (LDL) uptake (LDLR, APOB and PCSK9). Genetic diagnosis is particularly useful in asymptomatic children allowing for the detection of definite FH patients. Furthermore, defining their genetic status may be of considerable importance as the compound heterozygous status is much more severe than the heterozygous one. Our study aims at depicting the genetic background of an Italian pediatric population with FH focusing on the correlation between lipid profile and genetic status.
Methods
Out of 196 patients with clinically suspected FH (LDL-cholesterol [LDL-C] levels above 3.37 mmol/L, cholesterol level above 6.46 mmol/L in a first-degree relative or the presence of premature cardiovascular acute disease in a first/second-degree relative), we screened 164 index cases for mutations in the LDLR, APOB and PCSK9 genes.
Results
Patients with mutations (129/164) showed increased levels of LDL-C, 95th percentile-adjusted LDL-C and LDL/high-density lipoprotein (HDL) ratio and decreased levels of HDL-C, adjusted HDL-C. The association of the LDL/HDL ratio with the presence of mutations was assessed independently of age, (body mass index) BMI, parental hypercholesterolemia, premature coronary artery disease (CAD), triglycerides by multivariate logistic regression (odds ratio [OR]=1.701 [1.103–2.621], p=0.016). The LDL/HDL ratio gradually increased from patients without mutations to patients with missense mutations, null mutations and compound heterozygotes.
Conclusions
In conclusion, the LDL/HDL ratio proved to be a better parameter than LDL-C for discriminating patients with from patients without mutations across different genetic statuses.
Acknowledgments
We gratefully acknowledge the contribution of the Biobank of CEINGE and, in particular, of Dr. Annalisa Scotto di Frega for continued support of our work.
Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: This work was supported by MIUR funding under the project cod. PON03PE_00060_7, Italy.
Employment or leadership: None declared.
Honorarium: None declared.
Competing interests: The funding organization(s) played no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.
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Supplementary Material
The online version of this article offers supplementary material (https://doi.org/10.1515/cclm-2018-1037).
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