Longitudinal study of DNA methylation changes in patients with severe COVID-19

Aging is classically conceptualized as an ever-increasing trajectory of damage accumulation and loss of function, leading to increases in morbidity and mortality. However, recent in vitro studies have raised the possibility of age reversal. We characterized several models in which biological age, assessed primarily through analysis of DNA methylation, undergoes reversible changes. Severe COVID-19 is one such example. To test how biological age markers change over the course of severe infectious disease, we obtained longitudinal blood samples from patients with severe COVID-19. Our cohort consisted of patients who tested positive for COVID-19 by RT-PCR, were admitted to an intensive care unit, survived the disease, and provided multiple blood samples spanning the course of their hospitalization. DNA isolated from these samples was subjected to the Illumina Infinium MethylationEPIC array for methylation profiling.