Characteristics of Patients with Familial Hypercholesterolemia and Acute Coronary Syndrome Prescribed PCSK9 Inhibitors

Background: Patients with Familial Hypercholesterolemia (FH) or statin intolerance are significantly increasing. Therefore, a novel class of lipid-lowering drugs called Proprotein Convertase Subtilisin Kexin type 9 (PCSK9) inhibitors are prescribed for FH patients and statin intolerant. PCSK9 inhibitors are human monoclonal antibodies that slow down the LDL Receptor’s (LDLR) degradation by binding to PCSK9 adjacent to its binding site with LDL receptors, increasing LDL-C uptake and decreasing LDL-C blood level. Objectives: To evaluate the proper prescribing of PCSK9 inhibitors by measuring adherence to ACC/AHA and ESC/EAS guidelines at two tertiary care hospitals; King Fahad Medical City (KFMC), and Security Forces Hospital (SFH) - Riyadh - Saudi Arabia. Materials and Methods: An observational retrospective cohort study was carried out. Researchers included all patients started on PSCK9 inhibitors, specifically evolocumab for the last three years (from 2020 until the end of 2022) at SFH and KFMC. A data collection sheet (Excel sheet) with 51 questions (variables) is considered the primary research tool; the data were collected from the patient's medical files as another tool. Statistical analysis of categorical variables and continuous variables have been done using SPSS version 20 program. p-values less than 0.05 are deemed statistically significant. Results: Of the 201 patients, 142 (70.6%) were eligible for PCSK9 inhibitors treatment in accordance with ACC/AHA and ESC/EAS guidelines criteria. (66.7%) of patients were male, the mean age was (53.67±12.25) and (42.3%) were obese. Clinically, most of the patients had a history of a previous MI (70.1%), and (32.3%) had two major ASCVD. High-risk conditions were (69.2%) with hypertension and (63.2%) with diabetes. LDL-C level after 4-6 weeks of PCSK9 inhibitors initiation, was observed among the 161 (80.1%) cases of the study sample, while the attrition was in 40 (19.9%) cases. Statistical analysis measured a significant 37.1% reduction rate (p-value<0.001) from baseline to 6 weeks’ follow-up LDL-C laboratory confirmed post-treatment effect of PCSK9 inhibitors. The physicians' adherence to the ESC/EAS and ACC/AHA recommendations criteria in prescribing PSCK9 inhibitors was (70.6%). Conclusion: Most physicians adhered to the ESC/EAS and ACC/AHA recommendations criteria in prescribing PCSK9 inhibitors to FH patients and ACS patients. The results show that up to (70.6%) of physicians at King Fahad Medical City (KFMC) and Security Forces Hospital (SFH) adhere to ACC/AHA and ESC/EAS guidelines for prescribing PCSK9 inhibitors to FH patients and ACS patients this adherence was manifested by the number of patients (38%) who attained the LDL-C level≤1.8 mmol/L (≤70 mg/dL).