Coronary calcium score (CAC) appears to be independent of lipid profile in treated patients with Heterozygous Familial Hypercholesterolaemia

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Background Coronary artery calcium (CAC) score has been shown to improve the risk stratification and prediction of Atherosclerotic Cardiovascular Disease (ASCVD) in cohorts of patients with Heterozygous Familial Hypercholesterolaemia (FH) [i]. Objectives We sought to examine the CAC score in patients with FH who are on treatment and correlate to the therapy, Total Cholesterol (TC), Low Density Lipoprotein (LDL) and High-Density Lipoprotein (HDL) levels. Method Retrospective Analysis of patients with established diagnosis of FH from a specialist lipid clinic who underwent CAC for risk stratification. Results The study included 64 patients, of which 33 patients (52%) were males with an average age of 57.4 years. At diagnosis, the mean elevated TC level was 7.40 ±1.60 mmol/l. 37 patients (58%) were on statin, (7 patients were on Rosuvastatin 20 mg, 20 patients were on Atorvastatin 40 mg, 8 patients were on Atorvastatin 20 mg, 2 patients were on Atorvastatin 80 mg), 8 patients (12%) were on a combination of PCSK9 and statins, 3 patients (5%) were on fibrates (fenofibrates) 160 mg, 3 patients (5%) were on Ezetimibe 10 mg, 4 patients (6%) were on Bempedoic Acid 180 mg, 9 patients (15%) were on lifestyle modifications and did not prefer to start on any lipid lowering agents. 71% of patients with TC level of 7.29 ±1.87 mmol/l had a calcium score of less than 100. CAC of >100 was observed in 29% of patients with a TC level of 7.44 ±1.50 mmol/l. (p value of 0.741) CAC score >100 appeared independent of (A) LDL level (27% with a mean LDL level of 4.81±1.81 mmol/l versus 73% with a CAC <100 and a mean LDL level of 4.40 ±1.38mmol/l) (p value of 0.424) and of HDL level (29% of patients with a mean HDL level of 1.45 ±0.64mmol/l versus 71% with a CAC score< 100 with a mean HDL level of 1.44 ±0.61mmol/l) (p value of 0.768). Despite therapy, 45 patients (27 %) had high LDL level with a mean LDL level of 4.5 ±1.50mmol/l though we found no difference in CAC score between the two groups (p value of 0.424). Conclusion In a single centre retrospective analysis of patients with Heterozygous Familial Hypercholesterolaemia on therapy, there appears to be no correlation between the CAC score of more than 100 and baseline therapy, Total Cholesterol, LDL or HDL levels achieved. We postulate that more stringent LDL reduction to ~1.4mmol/l should be adopted with further analysis of Coronary calcium score in the long term.