Reports of “Long-COVID”, are rising but little is known about prevalence, risk factors, or whether it is possible to predict a protracted course early in the disease. We analysed data from 4182 incident cases of COVID-19 who logged their symptoms prospectively in the COVID Symptom Study app. 558 (13.3%) had symptoms lasting >=28 days, 189 (4.5%) for >=8 weeks and 95 (2.3%) for >=12 weeks. Long-COVID was characterised by symptoms of fatigue, headache, dyspnoea and anosmia and was more likely with increasing age, BMI and female sex. Experiencing more than five symptoms during the first week of illness was associated with Long-COVID, OR=3.53 [2.76;4.50]. A simple model to distinguish between short and long-COVID at 7 days, which gained a ROC-AUC of 76%, was replicated in an independent sample of 2472 antibody positive individuals. This model could be used to identify individuals for clinical trials to reduce long-term symptoms and target education and rehabilitation services.

Background: Frailty, increased vulnerability to physiological stressors, is associated with adverse outcomes. COVID-19 exhibits a more severe disease course in older, comorbid adults. Awareness of atypical presentations is critical to facilitate early identification. Objective: To assess how frailty affects presenting COVID-19 symptoms in older adults. Design: Observational cohort study of hospitalised older patients and self-report data for community-based older adults. Setting: Admissions to St Thomas’ Hospital, London with laboratory-confirmed COVID-19. Community-based data for older adults using the COVID Symptom Study mobile application. Subjects: Hospital cohort: patients aged 65 and over (n = 322); unscheduled hospital admission between 1 March 2020 and 5 May 2020; COVID-19 confirmed by RT-PCR of nasopharyngeal swab. Community-based cohort: participants aged 65 and over enrolled in the COVID Symptom Study (n = 535); reported test-positive for COVID-19 from 24 March (application launch) to 8 May 2020. Methods: Multivariable logistic regression analysis performed on age-matched samples from hospital and community-based cohorts to ascertain association of frailty with symptoms of confirmed COVID-19. Results: Hospital cohort: significantly higher prevalence of probable delirium in the frail sample, with no difference in fever or cough. Community-based cohort: significantly higher prevalence of possible delirium in frailer, older adults and fatigue and shortness of breath. Conclusions: This is the first study demonstrating higher prevalence of probable delirium as a COVID-19 symptom in older adults with frailty compared to other older adults. This emphasises need for systematic frailty assessment and screening for delirium in acutely ill older patients in hospital and community settings. Clinicians should suspect COVID-19 in frail adults with delirium.

Objectives: The aim of this study was to investigate GPT-3.5 in generating and coding medical documents with International Classification of Diseases (ICD)-10 codes for data augmentation on low-resource labels. Materials and Methods: Employing GPT-3.5 we generated and coded 9606 discharge summaries based on lists of ICD-10 code descriptions of patients with infrequent (or generation) codes within the MIMIC-IV dataset. Combined with the baseline training set, this formed an augmented training set. Neural coding models were trained on baseline and augmented data and evaluated on an MIMIC-IV test set. We report micro- and macro-F1 scores on the full codeset, generation codes, and their families. Weak Hierarchical Confusion Matrices determined within-family and outside-of-family coding errors in the latter codesets. The coding performance of GPT-3.5 was evaluated on prompt-guided self-generated data and real MIMIC-IV data. Clinicians evaluated the clinical acceptability of the generated documents. Results: Data augmentation results in slightly lower overall model performance but improves performance for the generation candidate codes and their families, including 1 absent from the baseline training data. Augmented models display lower out-of-family error rates. GPT-3.5 identifies ICD-10 codes by their prompted descriptions but underperforms on real data. Evaluators highlight the correctness of generated concepts while suffering in variety, supporting information, and narrative. Discussion and Conclusion: While GPT-3.5 alone given our prompt setting is unsuitable for ICD-10 coding, it supports data augmentation for training neural models. Augmentation positively affects generation code families but mainly benefits codes with existing examples. Augmentation reduces out-of-family errors. Documents generated by GPT-3.5 state prompted concepts correctly but lack variety, and authenticity in narratives.

Background: Multiple short delirium detection tools have been validated in research studies and implemented in routine care, but there has been little study of these tools in real‐world conditions. This systematic review synthesized literature reporting completion rates and/or delirium positive score rates of detection tools in large clinical populations in general hospital settings. Methods: PROSPERO (CRD42022385166). Medline, Embase, PsycINFO, CINAHL, and gray literature were searched from 1980 to December 31, 2022. Included studies or audit reports used a validated delirium detection tool performed directly with the patient as part of routine care in large clinical populations ( n ≥ 1000) within a general acute hospital setting. Narrative synthesis was performed. Results: Twenty‐two research studies and four audit reports were included. Tools used alone or in combination were the Confusion Assessment Method (CAM), 4 ‘A's Test (4AT), Delirium Observation Screening Scale (DOSS), Brief CAM (bCAM), Nursing Delirium Screening Scale (NuDESC), and Intensive Care Delirium Screening Checklist (ICDSC). Populations and settings varied and tools were used at different stages and frequencies in the patient journey, including on admission only; inpatient, daily or more frequently; on admission and as inpatient; inpatient post‐operatively. Tool completion rates ranged from 19% to 100%. Admission positive score rates ranged from: CAM 8%–51%; 4AT 13%–20%. Inpatient positive score rates ranged from: CAM 2%–20%, DOSS 6%–42%, and NuDESC 5–13%. Postoperative positive score rates were 21% and 28% (4AT). All but two studies had moderate–high risk of bias. Conclusions: This systematic review of delirium detection tool implementation in large acute patient populations found clinically important variability in tool completion rates, and in delirium positive score rates relative to expected delirium prevalence. This study highlights a need for greater reporting and analysis of relevant healthcare systems data. This is vital to advance understanding of effective delirium detection in routine care.

Booster COVID-19 vaccines have shown efficacy in clinical trials and effectiveness in real-world data against symptomatic and severe illness. However, some people still become infected with SARS-CoV-2 following a third (booster) vaccination. This study describes the characteristics of SARS-CoV-2 illness following a third vaccination and assesses the risk of progression to symptomatic disease in SARS-CoV-2 infected individuals with time since vaccination. This prospective, community-based, case-control study used data from UK-based, adult (≥18 years) users of the COVID Symptom Study mobile application, self-reporting a first positive COVID-19 test between June 1, 2021 and Apr 1, 2022. To describe the characteristics of SARS-CoV-2 illness following a third vaccination, we selected cases and controls who had received a third and second dose of monovalent vaccination against COVID-19 respectively and reported a first positive SARS-CoV-2 test at least 7 days after most recent vaccination. Cases and controls were matched (1:1) based on age, sex, BMI, time between first vaccination and infection, and week of testing. We used logistic regression models (adjusted for age, sex, BMI, level of social deprivation and frailty) to analyse associations of disease severity, overall disease duration, and individual symptoms with booster vaccination status. To assess potential waning of vaccine effectiveness, we compared disease severity, duration, and symptom profiles of individuals testing positive within 3 months of most recent vaccination (reference group) to profiles of individuals infected between 3-4, 4-5, and 5-6 months, for both third and second dose. All analyses were stratified by time period, based on the predominant SARS-CoV-2 variant at time of infection (Delta: June 1, 2021- 27 Nov, 2021; Omicron: 20 Dec, 2021-Apr 1, 2022). During the study period, 50,162 (Delta period) and 162,041 (Omicron) participants reported a positive SARS-CoV-2 test. During the Delta period, infection following three vaccination doses was associated with lower odds of long COVID (symptoms≥4weeks) (OR=0.83, CI[0.50-1.36], p<0.0001), hospitalization (OR=0.55, CI[0.39-0.75], p<0.0001) and severe symptoms (OR=0.36, CI[0.27-0.49], p<0.0001), and higher odds of asymptomatic infection (OR=3.45, CI[2.86-4.16], p<0.0001), compared to infection following only two vaccination doses. During the Omicron period, infection following three vaccination doses was associated with lower odds of severe symptoms (OR=0.48, CI[0.42-0.55], p<0.0001). During the Delta period, infected individuals were less likely to report almost all individual symptoms after a third vaccination. During the Omicron period, individuals were less likely to report most symptoms after a third vaccination, except for upper respiratory symptoms e.g. sneezing (OR=1.40, CI[1.18-1.35], p<0.0001), runny nose (OR=1.26, CI[1.18-1.35], p<0.0001), sore throat (OR=1.17, CI[1.10-1.25], p<0.0001), and hoarse voice (OR=1.13, CI[1.06-1.21], p<0.0001), which were more likely to be reported. There was evidence of reduced vaccine effectiveness during both Delta and Omicron periods in those infected more than 3 months after their most recent vaccination, with increased reporting of severe symptoms, long duration illness, and most individual symptoms. This study suggests that a third dose of monovalent vaccine may reduce symptoms, severity and duration of SARS-CoV-2 infection post-vaccination. For Omicron variants, third vaccination appears to reduce overall symptom burden, but may increase upper respiratory symptoms, potentially due to immunological priming. There is evidence of waning vaccine effectiveness against progression to symptomatic and severe disease and long COVID after three months. Our findings support ongoing booster vaccination promotion amongst individuals at high risk from COVID-19, to reduce severe symptoms and duration of illness, and health system burden. Disseminating knowledge on expected symptoms following booster vaccination may encourage vaccine uptake.

Aims: Delirium is common in hip fracture patients, but large-scale routine data studies examining the prevalence and associations of delirium at the time of initial presentation with a hip fracture are rare. This study aimed to describe the prevalence and outcomes of delirium on initial presentation with a hip fracture in a large national population sample.Methods: This study analyzed routinely collected national clinical registry data for all people in Scotland aged 50 years and over presenting with a hip fracture between 1 July 2019 and 31 December 2021. Delirium was assessed prospectively by clinicians as part of routine care using the 4AT, a validated two-minute assessment tool. Associations of 4AT score with mortality and return home within 30 days were analyzed using logistic regression models, adjusted for confounders.Results: Of 18,040 patients (mean age 80 years (SD 10); 70% female (n = 12,594)), 16,476 (91%) had a 4AT assessment on presentation and of these, 3,386 (21%) had a score ≥ 4, suggestive of delirium. Patients with delirium were older, more likely residing in care homes, and had higher American Society of Anesthesiologists grades (all p < 0.001). Delirium was independently associated with a twofold increased risk of inpatient mortality (adjusted odds ratio (aOR) 2.26 (95% CI 1.79 to 2.84)) and one-year mortality (aOR 2.05 (95% CI 1.83 to 2.29)), and a lower likelihood of returning home within 30 days (aOR 0.27 (95% CI 0.24 to 0.30)).Conclusion: Delirium affects around 20% of patients presenting with a hip fracture, and is associated with important adverse outcomes. Integrating delirium assessment into the initial clinical assessment of hip fracture patients is feasible at national scale, and should be considered as part of care for all hip fracture patients.Cite this article: Bone Joint J 2025;107-B(4):470–478.