Age-related Macular Degeneration Increases Risk of Severe COVID-19 Infection

Age-related macular degeneration (AMD) is a clinical risk factor for increased COVID-19 infection and mortality. AMD has been linked to a 25% increased risk of serious sequelae from SARS-CoV-2 infection, including respiratory failure and death, a risk higher than type 2 diabetes (21%) and obesity (13%).

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Genetic Link between Age-related Macular Degeneration and COVID-19

Taking these findings into account, Boston University Chobanian and Avedisian School of Medicine researchers hypothesized that AMD and COVID-19 share common genetic risk factors and designed and carried out a study that discovered a novel association between the two diseases and variants in the PDGFB gene. This gene encodes a platelet-derived growth factor (PDGF), which is involved in the aberrant blood vessel alterations that occur in AMD. They also discovered that worse COVID-19 outcomes were linked to AMD, most likely due to a genetic propensity to complement protein malfunction, as well as a greater quantity of PDGF in the serum.

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Age-related Macular Degeneration Increases Risk of COVID-19

“Our findings add to the body of evidence for the increased risk of infection and mortality from COVID-19 among AMD patients. Our analysis lends credence to previously reported clinical studies that found those with AMD have a higher risk for COVID-19 infection and severe disease, and that this increased risk may have a genetic basis,” explained co-corresponding author Lindsay A. Farrer, Ph.D., chief of biomedical genetics.

Using huge genetic databases containing tens of thousands of individuals, the BU research team conducted a genome-wide search for polymorphisms that are jointly related to AMD and each of three COVID-19 outcomes (infection rate, serious illness, and hospitalization). These datasets were previously created and investigated separately for genetic variables associated with AMD risk and each of the COVID-19 disease outcomes. Following that, the researchers reviewed publicly accessible data from patients with AMD or COVID-19, as well as control groups, to assess the correlation of PDGFB polymorphisms with gene activity. Finally, they used an analytical technique to look into the relationships between PDGFB gene variants, PDGFB levels in the blood, AMD, and COVID-19 results.

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Treatment of Age-related Macular Degeneration

According to the study, reducing PDGFB gene activity and serum PDGF levels may reduce the severity of COVID-19, especially in elderly adults. “Therapeutic strategies combining anti-VEGF therapy (a current treatment for AMD that limits blood vessel growth in the eye that can harm vision) with antagonists (drugs that bind to receptors) for blocking PDGF signaling have been considered even more effective than the single VEGF treatment and are currently under investigation in clinical trials,” added co-corresponding author Manju L. Subramanian, M.D., associate professor of ophthalmology.

The researchers feel that to further understand the overlapping pathology and risk factors that contribute to worsening clinical outcomes in both disease states, a larger sample size for critical illness and hospitalizations would be required.

Source-Medindia