Letter to the Editor: Variability but not admission or trends in NEWS2 score predicts clinical outcome in elderly hospitalised patients with COVID-19

Abstract

•In elderly COVID-19 inpatients, admission NEWS2 scores did not predict mortality.•Of components of NEW2 score, only systolic blood pressure predicted mortality.•A high variability in NEW2 score predicted mortality.•NEWS2 score does not consider the degree of supplemental oxygen patients require.•A more sensitive early warning score for COVID-19 is needed. In a recent article in the Journal, Bruno and colleagues present short-term outcomes in elderly patients with severe COVID-19 disease admitted to a single Italian Infectious Disease unit.1Bruno G. Perelli S. Fabrizio C. Buccoliero G.B. Short-term outcomes in individuals aged 75 or older with severe coronavirus disease (COVID-19): First observations from an Infectious Diseases Unit in Southern Italy.J Infect. 2020; (May 14S0163-4453(20)30301-7Epub ahead of print)https://doi.org/10.1016/j.jinf.2020.05.024Abstract Full Text Full Text PDF PubMed Scopus (10) Google Scholar The study found that elderly patients are at increased risk of adverse outcomes due to high number of comorbidities and emphasises the need to improve clinical management in these patients. In particular, elderly patients who are likely to deteriorate will need to be rapidly identified.2Ferguson N., Laydon D., Nedjati Gilani et al. Report 9: Impact of non-pharmaceutical interventions (NPIs) to reduce COVID19 mortality and healthcare demand. Online Report, accessed 7 April2020. https://spiral.imperial.ac.uk/handle/10044/1/77482Google Scholar Existing prognostic models for COVID-19 based on clinical, laboratory and radiological variables are at high risk of bias.3Wynants L. Van Calster B. Bonten M M.J. et al.Prediction models for diagnosis and prognosis of COVID-19 infection: systematic review and critical appraisal.BMJ. 2020; 369: m1328Crossref PubMed Scopus (1482) Google Scholar In the UK, the National Early Warning Score (NEWS) and its updated version NEWS2 – an a priori weighted composition of the patient's observations - is used routinely to monitor patients in hospital and identify early those who may deteriorate.4Royal College of Physicians. National Early Warning Score (NEWS 2). Updated 19 December 2017. Accessed 7 April2020. URL:https://www.rcplondon.ac.uk/projects/outputs/national-early-warning-score-news-2Google Scholar Compared to other early warning scores, the NEWS Score has a greater ability to discriminate patients at risk of cardiac arrest, unanticipated intensive care unit admission or death.5Smith G.B. Prytherch D.R. Meredith P. Schmidt P.E. Featherstone P.I. The ability of the National Early Warning Score (NEWS) to discriminate patients at risk of early cardiac arrest, unanticipated intensive care unit admission, and death.Resuscitation. 2013; 84: 465-470Abstract Full Text Full Text PDF PubMed Scopus (543) Google Scholar Currently, guidance from the National Institute of Clinical Excellence (NICE) supports the use of the NEWS2 score to risk assess patients with COVID-19 in the community, who may require hospitalisation.6NICE. COVID-19 rapid guideline: critical care in adults. Accessed 7 April2020. https://www.nice.org.uk/guidance/ng159Google Scholar In a recent rapid review, Greenhalgh and colleagues do not recommend using the NEWS2 Score alone for risk assessment of patients with COVID-19 in the community.7Greenhalgh T. Treadwell J. Burrow R. et al.Should we use NEWS2 to assess possible COVID-19 patients in primary care?.Centre for Evidence-Based Medicine. 2020; (Accessed 9 April)https://www.cebm.net/covid-19/should-we-use-the-news-or-news2-score-when-assessing-patients-with-possible-covid-19-in-primary-careGoogle Scholar Blood pressure and oxygen saturation measurements are difficult to take remotely. The score also does not include age or comorbidities, strong independent predictors of survival in patients with COVID-19. The value of the NEWS2 Score in predicting outcome in patients admitted to hospital with COVDI-19 remains uncertain. We therefore undertook, as part of service evaluation, a prospective pilot assessment of patients with confirmed COVID-19 admitted to a tertiary infectious diseases unit, in the first month of the pandemic reaching the UK. We studied all patients who had a clinical outcome (either discharged from hospital or died) between 12th March and 2nd April 2020. Clinical (presenting symptoms, comorbidity and the NEWS2 Score throughout hospital stay), laboratory (routine blood tests) and radiological (chest x-ray reports) findings on admission were collated. Our main aim was to examine the utility of the NEWS2 Score in predicting the clinical deterioration of hospitalised COVID-19 patients. Continuous data are expressed as a median (25th - 75th percentiles) and categorical data are expressed as n (%). Independent t-tests and Mann-Whitney U tests were used to compare two continuous variables for normally and non-normally distributed data. The chi-squared test was used to compare proportions between groups. Overall, 17 patients with COVID-19 had an outcome by 2nd April 2020. The median age of our cohort was 85 years (IQR 83-88 years); 53% were male and 82% were Caucasian. All patients who were unsuitable for escalation to intensive care and received ward-based care as per NICE rapid guidance for COVID-19.5Smith G.B. Prytherch D.R. Meredith P. Schmidt P.E. Featherstone P.I. The ability of the National Early Warning Score (NEWS) to discriminate patients at risk of early cardiac arrest, unanticipated intensive care unit admission, and death.Resuscitation. 2013; 84: 465-470Abstract Full Text Full Text PDF PubMed Scopus (543) Google Scholar The majority of patients died (N=10, 59%). Compared to patients who survived, those who died were more likely to be male, with bilateral consolidation on chest radiographs on admission. Admission SARS-CoV-2 quantitative PCR Ct values on nasopharyngeal swab did not seem to relate to survival. All patients who died required some form of oxygen therapy, ranging from nasal canulae to non-invasive ventilation through continuous positive airway pressure. Less than half of those who survived required oxygen therapy, all of which were delivered via nasal canulae. Fig. 1 shows the trend in the National Early Warning Score2 (NEWS2) throughout hospitalisation, stratified by severity of NEWS2 on admission and clinical outcome. First, we found that the initial NEWS2 score did not predict mortality. For example, four out of the ten patients (40%) who died presented with a NEWS2 score of 0-3 while three out of seven patients (43%) who survived presented with a NEW2 Score of 5 or above. Secondly, there was no significant difference in the admission NEWS2 score and its components, between patients who died and those who survived, apart from systolic blood pressure. (Table 1). Thirdly, examining the NEWS2 scores over time, patients who died had a higher variability in their scores compared to those who survived. Seven out of ten patients (70%) who died had a maximum daily change in NEWS2 score of over 5, while none of those who survived had such dramatic fluctuations. (Fig. 1)Table 1Baseline characteristics compared those who died vs those who survived.Died (N=10)Survived (N=7)P value (Died vs Survived)DemographicsAge86 (83-88)83 (82-88)0.59Sex (male), N (%)7 (70)2 (29)0.09Ethnicity, N (%)0.68Caucasian8 (80)6 (86)Asian Indian1 (10)1 (14)Black1 (10)0Number of comorbidities, N (%)001 (14)0.461-23 (30)2 (29)3+7 (70)4 (57)Ischaemic heart disease, N (%)1 (10)00.39Peripheral vascular disease, N (%)1 (10)2 (29)0.32Stroke, N (%)2 (20)1 (14)0.76Hypertension, N (%)6 (60)1 (14)0.06Atrial fibrillation, N (%)1 (10)2 (29)0.32Heart failure, N (%)1 (10)4 (57)0.04Diabetes, N (%)2 (20)1 (14)0.76Dementia, N (%)2 (20)1 (14)0.76Chronic kidney disease, N (%)1 (10)00.39Cancer, N (%)4 (40)1 (14)0.25COPD, N (%)2 (20)3 (43)0.31Obstructive sleep apnoea, N (%)2 (20)00.21Clinical frailty scale6 (5-7)6 (4-7)0.65Observations on admissionNEWS25 (0-8)3 (2-6)0.92Respiratory rate (breaths/min)21 (18-28)24 (20-28)0.69O2 saturation (%)96 (92-97)96 (93-98)0.96FiO2 (%)28 (21-100)21 (21-21)0.09Systolic blood pressure (mmHg)129 (124-133)146 (141-157)0.03Diastolic blood pressure (mmHg)74 (58-84)81 (66-98)0.26Heart rate (beats per minute)81 (74-95)84 (79-86)0.53Temperature (degree celcius)37.5 (36.8-38.5)37.4 (36.8-38.1)0.70Presenting complaintFever, N (%)8 (80)2 (29)0.03Cough, N (%)3 (30)5 (71)0.09Breathlessness, N (%)5 (50)4 (57)0.77Diarrhoea, N (%)03 (43)0.02Confusion, N (%)2 (20)2 (29)0.68Falls, N (%)1 (10)00.39Blood tests on admissionWhite cell count (x109/L)8.5 (3.7-15.9)7.3 (2.3-9.1)0.38Neutrophils (x109/L)6.8 (2.8-13.6)5.1 (1.8-8.0)0.33Lymphocyte (x109/L)0.99 (0.63-1.48)0.63 (0.31-1.07)0.14Haemoglobin (g/L)125 (113-142)116 (102-119)0.22Platelets (x109/L)173 (114-260)206 (135-261)0.38C-reactive protein (mg/L)65 (33-156)31 (9-110)0.24Sodium (mmol/L)133 (131-137)136 (131-138)0.46Potassium (mmol/L)4.7 (4.2-5.1)3.9 (3.4-4.4)0.03Urea (mmol/L)9.2 (7.0-15.9)7.2 (3.0-10.5)0.28Creatinine (µmol/L)122 (87-168)91 (57-119)0.12Chest radiographs (CXR - findings on admission) Total number during admission2 (1-3)1 (1-1)0.12 Clear3 (30)4 (57)0.007 Unilateral consolidation03 (43) Bilateral consolidation7 (70)0Ct Value (nasopharyngeal swab)22.51 (17.96-27.46)25.12 (18.54-31.04)0.40TreatmentOxygen therapy, N (%)10 (100)3 (43)0.006Nasal canulae, N (%)9 (90)3 (43)0.04Non-rebreathe mask, N (%)9 (90)0<0.001High-flow oxygen, N (%)3 (30)00.11Non-invasive ventilation, N (%)2 (20)00.21Length of stay (days)6 (4-13)9 (7-10)0.13 Open table in a new tab In our small pilot of elderly patients admitted to hospital with COVID-19, admission NEWS2 scores did not seem to be useful in predicting clinical outcomes. For some patients, death occurred regardless of admission NEWS scores and without a prior deteriorating trend. Originally, the NEWS score was developed using data from 35585 acute hospital admissions, most of whom would have had an underlying diagnosis of sepsis.8Prytherch D.R. Smith G.B. Schmidt P.E. Featherstone P.I. ViEWS–Towards a national early warning score for detecting adult inpatient deterioration.Resuscitation. 2010; 81: 932-937Abstract Full Text Full Text PDF PubMed Scopus (364) Google Scholar Sepsis is a clinical syndrome caused by overwhelming systemic bacterial infection. Clinical deterioration is seen within days in hospital. However, COVID-19 is caused by SARS-CoV-2, a coronavirus which predominately appears to affect the respiratory system as an initial viral pneumonitis. In China, a fifth of all COVID-19 inpatients rapidly became critically ill with hypoxia and respiratory failure.9Wu Z. McGoogan J.M. Characteristics of and important lessons from the coronavirus disease 2019 (COVID-19) outbreak in China: Summary of a report of 72314 cases from the Chinese Center for Disease Control and Prevention.JAMA. 2020; Crossref Scopus (10609) Google Scholar The weighting of the NEWS2 score does not account for the degree of supplemental oxygen (FiO2) a patient may require, thus limiting its utility to identify early deterioration in patients with COVID-19. In our cohort, patient 8 had a NEWS2 score of 2 on day 2 and 3 despite requiring a large increase in FiO2 (from room air to 60%). A more sensitive early warning score for COVID-19 needs to be urgently developed and validated.