Frailty and comorbidity in predicting community COVID-19 mortality in the UK Biobank: the effect of sampling

Abstract

Frailty has been linked to an increased risk of coronavirus disease 2019 (COVID-19)-associated mortality, but evidence has been inconclusive and limited to hospitalized older individuals. Using data from the UK Biobank, we assessed whether frailty and comorbidity predict COVID-19 mortality in the overall community population (n=437,555) and in a selected COVID-19 positive sample (n=2,059). Frailty was assessed using the Rockwood Frailty Index (FI) and the Hospital Frailty Risk Score (HFRS), whereas comorbidity was assessed by the Charlson Comorbidity Index (CCI). Overall, 408 individuals died of COVID-19, as ascertained from the death register data. In the full sample, HFRS (odds ratio [OR] 1.07; 95% confidence interval [CI] 1.06-1.07) and CCI (OR 1.14; 95% CI 1.08-1.20) were associated with increased risk of COVID-19 mortality, while FI was not statistically significantly different from null in the multivariable logistic regression model. Adding HFRS or CCI to a model with only age and sex resulted in significantly larger areas under the receiver operating characteristic curves. Nevertheless, when restricting the analyses to COVID-19 positive cases, which is a sample with over-representation of frail individuals, neither of the frailty measures or CCI added meaningful predictive accuracy on top of age and sex. Besides, we observed stronger associations between HFRS categories and COVID-19 mortality in relatively younger (<75 years) than older individuals (≥75 years). Our results suggest that HFRS and CCI, which could be readily derived from medical records, may be useful for COVID-19 mortality risk stratification in the community.

Assessing the age specificity of infection fatality rates for COVID-19: systematic review, meta-analysis, and public policy implications

“…Likewise, our metaregression does not include measures of comorbidities such as diabetes or obesity [156]. However, a recent study of data from a large representative and longitudinal sample collected by U.K. Biobank found that measures of frailty and comorbidity had only moderate effects in predicting COVID-19 mortality risk (i.e., increased odds of about 10%); moreover, that link was negligible among positive COVID-19 cases after accounting for age and sex [157]. See Supplementary Appendix S for additional evidence.…”

Metabolic dysfunction-associated fatty liver disease and liver function markers are associated with Crohn’s disease but not Ulcerative Colitis: a prospective cohort study

“…In addition, we included serum C-reactive protein concentration, Charlson Comorbidity Index (CCI), and self-reported usage of non-steroidal anti-inflammatory drugs. CCI was constructed based on 17 comorbidities with assigned weights associated with ICD codes from inpatient data [28]. The medication information was obtained from the baseline medication information in touch-screen questionnaires and verbal interview, including use of non-steroidal anti-inflammatory drugs, antibiotics, proton-pump inhibitors, hormonal replacement therapy, and oral contraceptive pills.…”

The association between frailty risk and COVID-19-associated all-mortality in hospitalised older people: a national cohort study

“…However, there is little difference in the rate of mortality between high and intermediate HFRS. This may be related to changes in the nature of the population presenting as a consequence of the national lockdown [ 28 ], or the availability of testing, which changed over the course of the pandemic. Indeed, we observed both changing populations presenting to acute care over the course of the pandemic (in part related to the imposition and subsequent lifting of lockdowns) and changing outcomes (perhaps related to changing treatment effects, such as the introduction of Dexamethasone [ 29 ]).…”