PCSK9 Inhibitors in a Statin-Intolerant Transgender Man With Heterozygous Familial Hypercholesterolemia: A Case Report

In female-to-male transgender individuals, testosterone is used to induce masculinization. Sex steroid therapy may increase circulating triglyceride and low-density lipoprotein cholesterol (LDL-C) levels and may decrease high-density lipoprotein cholesterol (HDL-C) levels, resulting in a more atherogenic lipid profile. These potentially adverse effects of androgen therapy may be exacerbated by the presence of familial hypercholesterolemia (FH). We describe the case of a transgender man with genetically diagnosed FH who was intolerant to statins and was started on a proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor to control his lipoproteins more effectively. The 35-year-old female-to-male transgender individual was referred to our center with a history of elevated LDL-C levels. Despite treatment with high doses of high-potency statins and ezetimibe, he had never achieved a sustained reduction in LDL-C; his levels of LDL-C were fluctuating between 170 and 344 mg/dL (4.4 and 8.9 mmol/L). Moreover, he developed side effects to statins in the form of myalgia and discontinued statin treatment. At the Sahlgrenska Lipid Clinic, a genetic diagnosis of heterozygous FH was established, and PCSK9 inhibitor therapy was started. The patient's LDL-C level has been reduced by approximately 40% for 23 months, and no adverse events have been reported.