Why continued lipoprotein apheresis is vital for homozygous familial hypercholesterolemia patients with COVID-19

Familial Hypercholesterolemia Patients with COVID-19-Effective Cholesterol-Lowering Therapy is Urgent both during and after Infection

Heterozygous familial hypercholesterolemia (HeFH) patients are the prime example of subjects who are at high risk for both acute myocardial infarction (AMI) and ischemic stroke during, and post, SARS-CoV-2 infection. HeFH per se, if left untreated, results in premature clinical atherosclerosis often presenting in the fourth or fifth decade of life. The other concern in HeFH is endothelial dysfunction which is already evident from early childhood. In untreated HeFH patients, the severe hypercholesterolemia causes endothelial dysfunction from an early age, and as a result thereof, atherosclerotic lesions develop prematurely, particularly in the coronary arteries, and result in further endothelial dysfunction and inflammation in these critical segments of the arterial tree. As the pre-existing endothelial dysfunction in HeFH patients is most likely sensitive to further direct and indirect SARS-CoV-2 virus-dependent damage, we can infer that HeFH serves as an example of a comorbidity that predicts a poorer prognosis with COVID-19 infection. Indeed, a large US national database study showed that patients diagnosed with HeFH and SARS-CoV-2 infection had significantly increased Annualized Incidence Density Rates (AIDRs) of AMI when compared to matched HeFH controls not having been diagnosed with SARS-CoV-2 infection. Effective cholesterol lowering is essential for the prevention, or at least alleviation, of the detrimental effects of SARS-CoV-2 infection among HeFH patients. Due to the pre-existing subclinical or even clinical atherosclerotic cardiovascular disease in subjects with HeFH, cholesterol-lowering treatment needs to be continued or, better still, intensified during, and for an extended period post, SARS-CoV-2 infection.

COVID-19 and Lipid Disorders

An elevated cholesterol concentration has been suspected to increase the susceptibility for SARS-COV-2 infection. Cholesterol plays a central role in the mechanisms of the SARS-COV-2 infection. In contrast, higher HDL-cholesterol levels seem to be protective. During COVID-19 disease, LDL-cholesterol and HDL-cholesterol appear to be decreased. On the other hand, triglycerides (also in different lipoprotein fractions) were elevated. Lipoprotein(a) may increase during this disease and is most probably responsible for thromboembolic events. This lipoprotein can induce a progression of atherosclerotic lesion formation. The same is suspected for the SARS-COV-2 infection itself. COVID-19 patients are at increased risk of incident cardiovascular diseases, including cerebrovascular disorders, dysrhythmias, ischemic and non-ischemic heart disease, pericarditis, myocarditis, heart failure, and thromboembolic disorders. An ongoing lipid-lowering therapy, including lipoprotein apheresis, is recommended to be continued during the COVID-19 disease, though the impact of lipid-lowering drugs or the extracorporeal therapy on prognosis should be studied in further investigations.