12 Being Non-Frail and Free From Cardiovascular Disease Reduces COVID-19 Risk in 269,164 Older UK Biobank Participants

Abstract

Background Older adults are at increased risk of COVID-19, resulting in public health shielding measures for all adults over 70 in the UK. Frailty has been proposed for risk stratification in COVID-19 with limited evidence. Cardiovascular risk factors hypertension, diabetes and raised BMI have been associated with increased COVID-19 risk. We sought to test if non-frail older adults with low cardiovascular risk had reduced COVID-19, to inform targeted shielding policies. Methods Fried and Rockwood frailty were ascertained at UK Biobank baseline (2006-2010) and electronic frailty index(eFI) in primary care data to 2017*. A cardiovascular disease risk score(CRS) consisting of smoking status, LDL-cholesterol, blood pressure, BMI, fasting glucose and physical activity was estimated at baseline. Frailty (baseline and eFI; eFI alone) and CRS were tested in logistic models against COVID-19 status and COVID-19 mortality to 14th June 2020 adjusted for demographics and technical covariates. Results N=269,164 UKB participants aged ≥65 at baseline (≥75years in 2020). 13.9% of COVID-19 positive were non-frail with low baseline CRS versus 41.8% frail with moderate/high CRS. Being non-frail and having low CRS were independently associated with reduced COVID-19. The composite of non-frail with low CRS compared to frail with moderate/high CRS had significantly reduced COVID-19 risk (composite non-frail with low CRS HR 0.61; 95% CI 0.45-0.84; p=0.0023; eFI non-frail with low CRS HR 0.16; 95%CI 0.07-0.36; p value=9.9x10-6) and COVID-19 mortality (composite non-frail HR 0.28; 95% CI 0.10-0.82; pvalue=0.02; eFI non-frail 0.07; 95% CI 0.02-0.28; pvalue=0.00014). Conclusion These results show that the COVID-19 risk in non-frail older adults with low cardiovascular risk was up to 84% lower than in those who were frail with cardiovascular risk factors. This could contribute to future work on stratification of shielding risk in older adults in future COVID-19 surges. *Planned data updates prior to the conference should enable updates to 2020.