The Impact of Biological Ageing on Clinical Severity in Hospitalized Covid-19 Patients

ABSTRACT

Background: Previous data has suggested that shorter telomere length (TL) is associated with higher risk of adverse COVID-19 outcomes, independent of several major risk factors for COVID-19 including age. Aim(s) We aimed at further exploring the relationship between TL and COVID-19 outcome in hospitalized patients. Method(s) 257 patients with proven COVID-19 infection with or without respiratory symptoms were included. Leucocyte TL was determined using qPCR (quantitative polymerase chain reaction) in leukocytes collected at the time of hospitalization. Clinical assessment related to disease severity and progress were collected from medical records, hospitalization duration, ventilation, early warning score (EWS) and clinical improvement using the WHO-scores. Result(s) Patients with longer TL at admission had less severe outcomes and a more rapid health improvement. the odds ratios for a 1-SD increment in TL associated with hospitalization duration were 0.58 (95%Cl 0.46-0.73 P<0.0001) unadjusted and 0.77 (95%Cl0.59-0.99 P=0.044) adjusted for age, sex, BMI, smoking, ethnicity and comorbidities. In men, a 1-SD increment in TL was associated with lower odds (adjusted OR=0.48 95%Cl 0.30-0.77 P=0.0015) to be on ventilation, and with a lower EWS at admission (adjusted s=0.13 95%Cl0.23-0.02 P=0.024). Finally, a 1-SD increment in TL in men was associated with a stronger decline in disease severity (based on WHOscores) after 30 days post-hospitalization(adjusted s=0.29 95%Cl0.56-0.03 P=0.029). Conclusion(s) Biological ageing forms an additional risk factor in COVID-19 infected patients to have more disease severity and progression. TL, especially in men, may form a biological basis in these observations.