External validation of the Oldham composite Covid-19 associated mortality model (OCCAM), a prognostic model for death in patients hospitalised with Covid-19

OBJECTIVE

External validation of the Oldham Composite Covid-19 associated Mortality Model (OCCAM), a prognostic model for Covid-19 mortality in hospitalised patients comprised of age, history of hypertension, current or previous malignancy, admission platelet count < 150 × 103/µL, admission CRP ≥ 100 µg/mL, acute kidney injury (AKI), and radiographic evidence of > 50% total lung field infiltrates.

PATIENTS AND METHODS

Retrospective study assessing discrimination (c-statistic) and calibration of OCCAM for death in hospital or within 30 days of discharge. 300 adults admitted to six district general and teaching hospitals in North West England for treatment of Covid-19 between September 2020 and February 2021 were included.

RESULTS

Two hundred and ninety-seven patients were included in the validation cohort analysis, with a mortality rate of 32.8%. The c-statistic was 0.794 (95% confidence interval 0.742-0.847) vs. 0.805 (95% confidence interval 0.766 - 0.844) in the development cohort. Visual inspection of calibration plots demonstrate excellent calibration across risk groups, with a calibration slope for the external validation cohort of 0.963.

CONCLUSION

The OCCAM model is an effective prognostic tool that can be utilised at the time of initial patient assessment to aid decisions around admission and discharge, use of therapeutics, and shared decision-making with patients. Clinicians should remain aware of the need for ongoing validation of all Covid-19 prognostic models in light of changes in host immunity and emerging variants.

Patient characteristics and predictors of mortality in 470 adults admitted to a district general hospital in England with Covid-19

Understanding risk factors for death from Covid-19 is key to providing good quality clinical care. We assessed the presenting characteristics of the 'first wave' of patients with Covid-19 at Royal Oldham Hospital, UK and undertook logistic regression modelling to investigate factors associated with death. Of 470 patients admitted, 169 (36%) died. The median age was 71 years (interquartile range 57-82), and 255 (54.3%) were men. The most common comorbidities were hypertension (n = 218, 46.4%), diabetes (n = 143, 30.4%) and chronic neurological disease (n = 123, 26.1%). The most frequent complications were acute kidney injury (AKI) (n = 157, 33.4%) and myocardial injury (n = 21, 4.5%). Forty-three (9.1%) patients required intubation and ventilation, and 39 (8.3%) received non-invasive ventilation. Independent risk factors for death were increasing age (odds ratio (OR) per 10 year increase above 40 years 1.87, 95% confidence interval (CI) 1.57-2.27), hypertension (OR 1.72, 95% CI 1.10-2.70), cancer (OR 2.20, 95% CI 1.27-3.81), platelets <150 × 103/μl (OR 1.93, 95% CI 1.13-3.30), C-reactive protein ≥100 μg/ml (OR 1.68, 95% CI 1.05-2.68), >50% chest radiograph infiltrates (OR 2.09, 95% CI 1.16-3.77) and AKI (OR 2.60, 95% CI 1.64-4.13). There was no independent association between death and gender, ethnicity, deprivation level, fever, SpO2/FiO2, lymphopoenia or other comorbidities. These findings will inform clinical and shared decision making, including use of respiratory support and therapeutic agents.

Diagnostic and treatment behaviour in children with chronic respiratory symptoms: relationship with socioeconomic factors

BACKGROUND

The prevalence and severity of asthma is believed to increase with increasing socioeconomic deprivation. The relationship between asthma diagnosis, symptoms, diagnostic accuracy, and socioeconomic deprivation as determined by Townsend scores was determined in Sheffield schoolchildren.

METHODS

All 6021 schoolchildren aged 8-9 years in one school year in Sheffield were given a parent respondent survey based on International Survey of Asthma and Allergies in Childhood (ISAAC) questions.

RESULTS

5011/6021 (83.2%) questionnaires were returned. Postcode data were available in 4131 replies (82.4%) and were used to assign a composite deprivation score (Townsend score). Scores were divided into five quintiles, with group 1 being least and group 5 being most deprived. A positive trend was observed from group 1 to group 5 for the prevalence of wheeze in the previous 12 months, wheeze attacks >or=4/year, nocturnal wheeze and cough (all p<0.001), cough and/or wheeze "most times" with exertion (p<0.03), current asthma (p<0.001), and significant asthma symptoms (p<0.001). No significant trend was observed for lifetime wheeze or attacks of speech limiting wheeze. There were no significant trends in the prevalence of current asthmatic children without significant symptoms (overdiagnosis) or children with significant asthma symptoms but no current asthma diagnosis (underdiagnosis) across the social groups. There was a significant negative trend in the ratio of asthma medication to asthma diagnosis from least to most deprived groups (p<0.001).

CONCLUSIONS

Asthma morbidity and severity increase according to the level of socioeconomic deprivation. This may be due to differences in environment, asthma management, and/or symptom reporting. Diagnostic accuracy does not vary significantly across deprivation groups but children living in areas of least deprivation and taking asthma medication are less likely to be labelled as having asthma, suggesting diagnostic labelling bias.

Increasing prevalence of asthma diagnosis and symptoms in children is confined to mild symptoms

BACKGROUND

The prevalence of childhood asthma is increasing but few studies have investigated trends in asthma severity. We investigated trends in asthma diagnosis and symptom morbidity between an eight year time period in a paired prevalence study.

METHODS

All children in one single school year aged 8-9 years in the city of Sheffield were given a parent respondent questionnaire in 1991 and 1999 based on questions from the International Survey of Asthma and Allergy in Children (ISAAC). Data were obtained regarding the prevalence of asthma and wheeze and current (12 month) prevalences of wheeze attacks, speech limiting wheeze, nocturnal cough and wheeze, and exertional symptoms.

RESULTS

The response rates in 1991 and 1999 were 4580/5321 (85.3%) and 5011/6021 (83.2%), respectively. There were significant increases between the two surveys in the prevalence of asthma ever (19.9% v 29.7%, mean difference 11.9%, 95% confidence interval (CI) 10.16 to 13.57, p<0.001), current asthma (10.3% v 13.0%, mean difference 2.7%, 95% CI 1.44 to 4.03, p<0.001), wheeze ever (30.3% v 35.8%, mean difference 5.7%, 95% CI 3.76 to 7.56, p<0.001), wheeze in the previous 12 months (17.0% v 19.4%, mean difference 2.5, 95% CI 0.95 to 4.07, p<0.01), and reporting of medication use (16.9% v 20%, mean difference 3.0%, 95% CI 1.46 to 4.62, p<0.001). There were also significant increases in reported hayfever and eczema diagnoses.

CONCLUSIONS

Diagnostic labelling of asthma and lifetime prevalence of wheeze has increased. The current 12 month point prevalence of wheeze has increased but this is confined to occasional symptoms. The increased medication rate may be responsible for the static prevalence of severe asthma symptoms. The significant proportion of children receiving medication but reporting no asthma symptoms identified from our 1999 survey suggests that some children are being inappropriately treated or overtreated.