Familial Hypercholesterolemia: Real-World Data of 1236 Patients Attending a Czech Lipid Clinic. A Retrospective Analysis of Experience in More than 50 years. Part I: Genetics and Biochemical Parameters
Abstract
Introduction: The cause of familial hypercholesterolemia (FH) is defect in LDL receptor or familial defect of apolipoprotein B-100 (FDB) or, rarely, defect in proprotein convertase subtilisin/kexin type 9. Identification and treatment of patients with FH improves their prognosis.
Our data represent retrospective analysis of 50 years of specialised care in our center.Patients and Methods: A group of 1236 FH patients (841 women, 395 men; 993 study subjects and 243 relatives; mean age 44.8 +/- 16.7 years) included 154 FDB patients followed at the Lipid Clinic of the General University Hospital in Prague since the mid-1960s to the present. Clinical diagnosis was based on the Dutch Lipid Clinic Network Criteria.
Genetic analysis was performed using PCR-RFLP to detect FDB and apolipoprotein E (APOE) polymorphism. Biochemical data were collected and statistically analysed.Results: At baseline, mean LDL-C and total cholesterol (TC) levels of all FH patients combined were 6.49 +/- 1.92 mmol/L and 8.95 +/- 1.95 mmol/L, respectively.
Their LDL-C levels decreased to 3.26 +/- 1.57 mmol/L and TC levels to 5.43 +/- 1.69 mmol/L during follow-up. In the subgroup of LDL receptor-mediated FH (non-FDB) patients, baseline LDL-C and TC levels of 6.61 +/- 1.95 mmol/L and 9.09 +/- 1.97 mmol/L declined to 3.21 +/- 1.60 mmol/L and 5.39 +/- 1.72 mmol/L, respectively, during follow-up.
In the FDB subgroup of patients, baseline levels of LDL-C and TC were 5.57 +/- 1.46 mmol/L and 7.88 +/- 1.58 mmol/L decreasing to 3.45 +/- 0.24 mmol/L and 5.58 +/- 1.37 mmol/L, respectively, during follow-up. Differences were also found in the effects of various APOE isoforms on lipid lowering.
A significant decrease in lipid parameters was observed with the E2E2 isoform whereas a minimal decrease was seen with the E4E4 and E3E3 isoforms.Conclusion: Whereas, overall, non-FDB patients had higher baseline lipid levels, these levels declined more appreciably compared with FDB patients during follow-up. Our retrospective analysis also found different effects of APOE isoforms on the decrease in lipid levels.