African-Americans with a certain genetic variant that puts them at increased risk of sudden cardiac death — along with socioeconomic and cultural factors — could contribute to the racial health disparities seen among COVID-19 victims.
Writing in the journal Heart Rhythm, the official publication of the Heart Rhythm Society and the Cardiac Electrophysiology Society, published by Elsevier, investigators also note that the unwanted effects of potential therapies like hydroxychloroquine could put African-Americans with the genetic variant at increased risk of “drug-induced ventricular arrhythmias.”
“Without a definitive explanation for the increased COVID 19-related mortality rates observed among individuals of African descent, we need to consider all potential contributors, including the possibility of genetic predispositions,” explained first author John R. Giudicessi, of the Department of Cardiovascular Medicine at Mayo Clinic, in Rochester, Minn.
“The African-specific p.Ser1103Tyr-SCN5A common ion channel variant is a reasonable place to start, as its proarrhythmic potential is awakened by risk factors observed in hospitalized COVID-19 patients – namely, hypoxemia, electrolyte abnormalities, and QT-prolonging drug use,” he said in a statement.
As recent studies have shown that hydroxychloroquine is not effective in the treatment of sick, hospitalized COVID-19 patients, the authors advocate against its use in that setting.
According to investigators, the proarrhythmic potential associated with p.Ser1103Tyr-SCN5A can be enhanced by drugs that can cause irregular heartbeat, as well as some antibiotics and antifungal medications.
African-American infants with the p.Ser1103Tyr-SCN5A variant are over-represented in sudden infant death syndrome, and mechanisms underlying hypoxia — where a region of the body is deprived of adequate oxygen supply — may be responsible. Scientists say that the hypoxia seen in many COVID-19 patients raises a concern that p.Ser1103Tyr-SCN5A could produce a similar, African-American susceptibility to ventricular arrhythmia and sudden cardiac death from the SARS-CoV-2 infection.
One in 13 African-Americans may be at substantially increased risk for potentially lethal ventricular arrhythmia during the COVID-19 pandemic, according to the data reviewed by scientists.
However, investigators admit that it remains to be seen whether population-specific genetic risk factors are contributing to the spike in sudden deaths and racial health disparities observed in COVID-19 epicenters.
“The genetic variant p.Ser1103Tyr-SCN5A, is a potentially proarrhythmic, sudden cardiac death marker for African Americans, and seeking its presence and respecting it is long overdue,” explained senior author and genetic cardiologist Michael J. Ackerman, Department of Cardiovascular Medicine, at the Mayo Clinic.
As of Monday afternoon, there were more than 2.1 million infections and 115,998 deaths from COVID-19 in the U.S.