Abstract
Objectives: The Intermountain Risk Score (IMRS), composed using published sex-specific weightings of parameters in the complete blood count (CBC) and basic metabolic profile (BMP), is a validated predictor of mortality. We hypothesised that IMRS calculated from prepandemic CBC and BMP predicts COVID-19 outcomes and that IMRS using laboratory results tested at COVID-19 diagnosis is also predictive.
Design: Prospective observational cohort study.
Setting: Primary, secondary, urgent and emergent care, and drive-through testing locations across Utah and in sections of adjacent US states. Viral RNA testing for SARS-CoV-2 was conducted from 3 March to 2 November 2020.
Participants: Patients aged ≥18 years were evaluated if they had CBC and BMP measured in 2019 and tested positive for COVID-19 in 2020.
Primary and secondary outcome measures: The primary outcome was a composite of hospitalisation or mortality, with secondary outcomes being hospitalisation and mortality separately.
Results: Among 3883 patients, 8.2% were hospitalised and 1.6% died. Subjects with low, mild, moderate and high-risk IMRS had the composite endpoint in 3.5% (52/1502), 8.6% (108/1256), 15.5% (152/979) and 28.1% (41/146) of patients, respectively. Compared with low-risk, subjects in mild-risk, moderate-risk and high-risk groups had HR=2.33 (95% CI 1.67 to 3.24), HR=4.01 (95% CI 2.93 to 5.50) and HR=8.34 (95% CI 5.54 to 12.57), respectively. Subjects aged <60 years had HR=3.06 (95% CI 2.01 to 4.65) and HR=7.38 (95% CI 3.14 to 17.34) for moderate and high risks versus low risk, respectively; those ≥60 years had HR=1.95 (95% CI 0.99 to 3.86) and HR=3.40 (95% CI 1.63 to 7.07). In multivariable analyses, IMRS was independently predictive and was shown to capture substantial risk variation of comorbidities.
Conclusions: IMRS, a simple risk score using very basic laboratory results, predicted COVID-19 hospitalisation and mortality. This included important abilities to identify risk in younger adults with few diagnosed comorbidities and to predict risk prior to SARS-CoV-2 infection.
Keywords: COVID-19; epidemiology; preventive medicine; public health.
【저자키워드】 COVID-19, Epidemiology, public health., Preventive medicine, 【초록키워드】 public health, SARS-CoV-2, Mortality, SARS-COV-2 infection, Variation, Comorbidities, Comorbidity, risk, outcome, RNA, CBC, Laboratory results, complete blood count, Prospective, COVID-19 diagnosis, Mild, group, Utah, hospitalisation, Care, moderate, patients, predict, score, high risk, Predictive, composite endpoint, Observational cohort study, Primary outcome, 95% CI, subject, secondary outcome, multivariable analyses, positive, COVID-19 hospitalisation, parameter, substantial risk, Weighting, hospitalised, shown, tested, predicted, identify, died, composed, diagnosed, evaluated, conducted, calculated, BMP, hypothesised, laboratory result, 【제목키워드】 Cohort, Health, Patient, score, positive, event,