The impact of genetic testing on physician practice in specialized cardiovascular clinics.

Although familial hypercholesterolemia (FH) is a US Centers for Disease Control and Prevention tier 1 condition for genetic testing, the impact of testing on clinical outcomes is unclear. We aimed to assess whether genetic testing alters lipid management in HeartCare participants. For participants with pathogenic/likely pathogenic variants for FH observed at Baylor College of Medicine cardiology clinics, data on laboratory values, medication prescriptions, and diagnoses were collected and compared before and after genetic testing. In the 20 participants with APOB/LDLR variants and complete data, low-density lipoprotein cholesterol (LDL-C) was numerically lower but not significantly different before vs after genetic testing (103 vs 79.5 mg/dL). Sixteen (80%) participants were from the lipid clinic; the majority had a preexisting FH diagnosis. LDL-C levels were numerically lower, and more patients received proprotein convertase subtilisin/kexin type 9 inhibitor prescriptions after genetic testing; however, the difference was not statistically significant. The majority of patients with FH achieved LDL-C <100 mg/dL after genetic testing; however, most patients with APOB/LDLR variants were from the lipid clinic and had been diagnosed with FH by clinical criteria.