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Background: Covid-19 healthcare worker testing, isolation and quarantine policies had to balance risks to patients from the virus and from staff absence. The emergence of the Omicron variant led to dangerous levels of key-worker absence globally. We evaluated whether using two manufacturers' lateral flow tests (LFTs) concurrently improved SARS-CoV-2 Omicron detection significantly and was acceptable to hospital staff. In a nested study, to understand risks of return to work after a 5-day isolation/quarantine period, we examined virus culture 5–7 days after positive test or significant exposure. Methods: Fully-vaccinated Liverpool (UK) University Hospitals staff participated (February-May 2022) in a random-order, open-label trial testing whether dual LFTs improved SARS-CoV-2 detection, and whether dual swabbing was acceptable to users. Participants used nose-throat swab Innova and nose-only swab Orient Gene LFTs in daily randomised order for 10 days. A user-experience questionnaire was administered on exit. Selected participants gave swabs for viral culture on days 5–7 after symptom onset or first positive test. Cultures were considered positive if cytopathic effect was apparent or SARS-CoV-2 N gene sub-genomic RNA was detected. Results: Two hundred and twenty-six individuals reported 1466 pairs of LFT results. Tests disagreed in 127 cases (8.7%). Orient Gene was more likely (78 cf. 49; OR: 2.1, 1.1–4.1; P = 0.03) to be positive. If Innova was swabbed second, it was less likely to agree with a positive Orient Gene result (OR: 2.7, 1.3–5.2; P = 0.005); swabbing first with Innova made no significant difference (OR: 1.1, 0.5–2.3; P = 0.85). Orient Gene positive Innova negative result-pairs became more frequent over time (OR: 1.2, 1.1–1.3; P < 0.001). Of individuals completing the exit questionnaire, 90.7% reported dual swabbing was easy, 57.1% said it was no barrier to their daily routine and 65.6% preferred dual testing. Respondents had more confidence in dual versus single test results. Viral cultures from days 5–7 were positive for 6/31 (19.4%, 7.5%-37.5%) and indeterminate for 11/31 (35.5%, 19.2%-54.6%) LFT-positive participants, indicating they were likely still infectious. Conclusions: Dual brand testing increased LFT detection of SARS-CoV-2 antigen by a small but meaningful margin and was acceptable to hospital workers. Viral cultures demonstrated that policies recommending safe return to work ~ 5 days after Omicron infection/exposure were flawed. Key-workers should be prepared for dynamic self-testing protocols in future pandemics. Trial registration: https://www.isrctn.com/ISRCTN47058442 (26 January 2022). [ABSTRACT FROM AUTHOR]

Aims: Systematic annual screening to detect sight‐threatening diabetic retinopathy (STDR) is established in the United Kingdom. We designed an observational cohort study to provide up‐to‐date data for policy makers and clinical researchers on incidence of key screening endpoints in people with diabetes attending one screening programme running for over 30 years. Methods: All people with diabetes aged ≥12 years registered with general practices in the Liverpool health district were offered inclusion. Data sources comprised: primary care (demographics, systemic risk factors), Liverpool Diabetes Eye Screening Programme (retinopathy grading), Hospital Eye Services (slit lamp biomicroscopy assessment of screen positives). Results: 133,366 screening episodes occurred in 28,384 people over 11 years. Overall incidences were: screen positive 6.7% (95% CI 6.5–6.8), screen positive for retinopathy 3.1% (3.0–3.1), unassessable images 2.6% (2.5–2.7), other significant eye diseases 1.0% (1.0–1.1). 1.6% (1.6–1.7) had sight‐threatening retinopathy confirmed by slit lamp biomicroscopy. The annual incidence of screen positive and screen positive for retinopathy showed consistent declines from 8.8%–10.6% and 4.4%–4.6% in 2007/09 to 4.4%–6.8% and 2.3%–2.9% in 2013/17, respectively. Rates of STDR (true positive) were consistently below 2% after 2008/09. Screen positive rates were higher in first time attenders (9.9% [9.4–10.2] vs. 6.1% [6.0–6.2]) in part due to ungradeable images (4.1% vs. 2.3%) and other eye disease (2.4% vs. 0.8%). 4.5% (3.9–5.2) of previous non‐attenders had sight‐threatening retinopathy. Compared with people with type 2 diabetes, those with type 1 disease demonstrated higher rates of screen positive (11.9% vs. 6.0%) and STDR (6.4% vs. 1.2%). Overall prevalence of any retinopathy was 27.2% (27.0–27.4). Conclusions: In an established screening programme with a stable population screen, positive rates show a consistent fall over time to a low level. Of those who are screen positive, fewer than 50% are screen positive for diabetic retinopathy. Most are due to sight threatening maculopathy. The annual incidence of STDR is under 2% suggesting future work on redefining screen positive and supporting extended intervals for people at low risk. Higher rates of screen positive and STDR are seen in first time attenders. Those who have never attended for screening should be specifically targeted. [ABSTRACT FROM AUTHOR]

Visual field assessment is an important clinical evaluation for eye disease and neurological injury. We evaluated Octopus semi-automated kinetic peripheral perimetry (SKP) and Humphrey static automated central perimetry for detection of neurological visual field loss in patients with pituitary disease. We carried out a prospective cross-sectional diagnostic accuracy study comparing Humphrey central 30-2 SITA threshold programme with a screening protocol for SKP on Octopus perimetry. Humphrey 24-2 data were extracted from 30-2 results. Results were independently graded for presence/absence of field defect plus severity of defect. Fifty patients (100 eyes) were recruited (25 males and 25 females), with mean age of 52.4 years (SD = 15.7). Order of perimeter assessment (Humphrey/Octopus first) and order of eye tested (right/left first) were randomised. The 30-2 programme detected visual field loss in 85%, the 24-2 programme in 80%, and the Octopus combined kinetic/static strategy in 100% of eyes. Peripheral visual field loss was missed by central threshold assessment. Qualitative comparison of type of visual field defect demonstrated a match between Humphrey and Octopus results in 58%, with a match for severity of defect in 50%. Tests duration was 9.34 minutes (SD = 2.02) for Humphrey 30-2 versus 10.79 minutes (SD = 4.06) for Octopus perimetry. Octopus semi-automated kinetic perimetry was found to be superior to central static testing for detection of pituitary disease-related visual field loss. Where reliant on Humphrey central static perimetry, the 30-2 programme is recommended over the 24-2 programme. Where kinetic perimetry is available, this is preferable to central static programmes for increased detection of peripheral visual field loss. [ABSTRACT FROM AUTHOR]

Background: Currently, no generally approved medical treatment can delay the onset of age-related macular degeneration (AMD) or slow the progression of degenerative changes. Repurposing drugs with beneficial effects on AMD pathophysiology offers a route to new treatments which is faster, cost-effective, and safer for patients. Recent studies indicate a potential role for metformin in delaying AMD development and progression. In this context, we conducted a systematic review and meta-analysis to look for beneficial associations between metformin and AMD. Methods: We systematically searched Medline and Embase (via Ovid), Web of Science, and ClinicalTrials.gov databases for clinical studies in humans that examined the associations between metformin treatment and AMD published from inception to February 2021. We calculated pooled odds ratio (OR) with 95% confidence interval (CI) considering a random effect model in the meta-analysis. Results: Five retrospective studies met the inclusion criteria. There are no prospective studies that have reported the effect of metformin in AMD. The meta-analysis showed that people taking metformin were less likely to have AMD although statistical significance was not met (pooled adjusted OR = 0.80, 95% CI 0.54–1.05, I2 = 98.8%). Subgroup analysis of the association between metformin and early and late AMD could not be performed since the data was not available from the included studies. Conclusions: Analysis of retrospective data suggests a signal that metformin may be associated with decreased risk of any AMD. It should be interpreted with caution because of the failure to meet statistical significance, the small number of studies, and the limitation of routine record data. However prospective studies are warranted in generalizable populations without diabetes, of varied ethnicities, and AMD stages. Clinical trials are needed to determine if metformin has efficacy in treating early and late-stage AMD. [ABSTRACT FROM AUTHOR]

Aims: To evaluate our proposed multivariate approach to identify patients who will develop sight‐threatening diabetic retinopathy (STDR) within a 1‐year screen interval, and explore the impact of simple stratification rules on prediction. Materials and methods: A 7‐year dataset (2009‐2016) from people with diabetes (PWD) was analysed using a novel multivariate longitudinal discriminant approach. Level of diabetic retinopathy, assessed from routine digital screening photographs of both eyes, was jointly modelled using clinical data collected over time. Simple stratification rules based on retinopathy level were also applied and compared with the multivariate discriminant approach. Results: Data from 13 103 PWD (49 520 screening episodes) were analysed. The multivariate approach accurately predicted whether patients developed STDR or not within 1 year from the time of prediction in 84.0% of patients (95% confidence interval [CI] 80.4‐89.7), compared with 56.7% (95% CI 55.5‐58.0) and 79.7% (95% CI 78.8‐80.6) achieved by the two stratification rules. While the stratification rules detected up to 95.2% (95% CI 92.2‐97.6) of the STDR cases (sensitivity) only 55.6% (95% CI 54.5‐56.7) of patients who did not develop STDR were correctly identified (specificity), compared with 85.4% (95% CI 80.4‐89.7%) and 84.0% (95% CI 80.7‐87.6%), respectively, achieved by the multivariate risk model. Conclusions: Accurate prediction of progression to STDR in PWD can be achieved using a multivariate risk model whilst also maintaining desirable specificity. While simple stratification rules can achieve good levels of sensitivity, the present study indicates that their lower specificity (high false‐positive rate) would therefore necessitate a greater frequency of eye examinations. [ABSTRACT FROM AUTHOR]

Background: From January to May 2021 the alpha variant (B.1.1.7) of SARS-CoV-2 was the most commonly detected variant in the UK. Following this, the Delta variant (B.1.617.2) then became the predominant variant. The UK COVID-19 vaccination programme started on 8th December 2020. Prior to the Delta variant, most vaccine effectiveness studies focused on the alpha variant. We therefore aimed to estimate the effectiveness of the BNT162b2 (Pfizer-BioNTech) and the ChAdOx1 nCoV-19 (Oxford-AstraZeneca) vaccines in preventing symptomatic and asymptomatic infection with respect to the Delta variant in a UK setting.Methods: We used anonymised public health record data linked to infection data (PCR) using the Combined Intelligence for Population Health Action resource. We then constructed an SIR epidemic model to explain SARS-CoV-2 infection data across the Cheshire and Merseyside region of the UK. Vaccines were assumed to be effective after 21 days for 1 dose and 14 days for 2 doses.Results: We determined that the effectiveness of the Oxford-AstraZeneca vaccine in reducing susceptibility to infection is 39% (95% credible interval [34, 43]) and 64% (95% credible interval [61, 67]) for a single dose and a double dose respectively. For the Pfizer-BioNTech vaccine, the effectiveness is 20% (95% credible interval [10, 28]) and 84% (95% credible interval [82, 86]) for a single-dose and a double dose respectively.Conclusion: Vaccine effectiveness for reducing susceptibility to SARS-CoV-2 infection shows noticeable improvement after receiving two doses of either vaccine. Findings also suggest that a full course of the Pfizer-BioNTech provides the optimal protection against infection with the Delta variant. This reinforces the need to complete the full course programme to maximise individual protection and reduce transmission. [ABSTRACT FROM AUTHOR]

Background: Varying the intervals in retinopathy screening informed by personal risk offers reallocation of resources to better target high risk groups and address the increasing prevalence of diabetes. However, safety data especially on extended intervals is minimal. Aim: To evaluate the safety, efficacy and cost effectiveness (CE) of individualized variable-interval risk-based screening in a population setting compared to usual care. Methods: Masked 2 arm, parallel assignment, equivalence RCT (largest to date in screening) with independent trials unit monitoring in people with diabetes aged ≥12 years attending screening in a single English program. Randomization was 1:1 to individualized screening (active group; 6, 12 or 24 months for high, medium and low risk) determined by a risk calculation engine using real-time local demographic, retinal and clinical data, compared with annual screening (control). CE analysis measuring NHS and societal costs took a 2-year time horizon. Findings: 4534 participants entered the study - after withdrawals/loss to follow-up: active 2097; control 2224. Attendance rates at first follow-up visit (primary outcome, safety) were equivalent (per protocol analysis, 5% margin): active 83.6% control 84.7% (difference 1.0, 90% CI -0.8, 2.9). STDR detection rates were non-inferior (1.5% margin): active 1.43% control 1.71% (difference -0.28, CI -0.93, 0.36). Quality of life (EQ5D5L, HUI3) was not significantly different between the groups. Incremental cost saving per person was £18.75 (NHS cost) rising to £49.96 with societal costs. A 39.3% reduction in number of appointments was seen. Conclusions: All parties involved in diabetes care can be reassured that extended and personalized screening intervals can safely be introduced in established screening program. Scale-up with further validation outside a research setting is recommended. Views expressed are solely those of the authors. Disclosure: D.M. Broadbent: None. A. Wang: None. C.P. Cheyne: None. J.G. Lathe: None. I.M. Stratton: Consultant; Self; Novo Nordisk A/S. Research Support; Self; Bayer AG, Boehringer Ingelheim International GmbH. J. Vora: None. M. Garcia-Finana: None. M. James: None. S.P. Harding: None. Funding: UK National Institute for Health Research [ABSTRACT FROM AUTHOR]

Background: Visual problems are an under-reported sequela following stroke. The aim of this study is to report annual incidence and point prevalence of visual problems in an acute adult stroke population and to explore feasibility of early timing of visual assessment. Methods and findings: Multi-centre acute stroke unit, prospective, epidemiology study (1st July 2014 to 30th June 2015). Orthoptists reviewed all patients with assessment of visual acuity, visual fields, ocular alignment, ocular motility, visual inattention and visual perception. 1033 patients underwent visual screening at a median of 3 days (IQR 2) and full visual assessment at a median of 4 days (IQR 7) after the incident stroke: 52% men, 48% women, mean age 73 years and 87% ischaemic strokes. Excluding pre-existent eye problems, the incidence of new onset visual sequelae was 48% for all stroke admissions and 60% in stroke survivors. Three quarters 752/1033 (73%) had visual problems (point prevalence): 56% with impaired central vision, 40% eye movement abnormalities, 28% visual field loss, 27% visual inattention, 5% visual perceptual disorders. 281/1033 (27%) had normal eye exams. Conclusions: Incidence and point prevalence of visual problems in acute stroke is alarmingly high, affecting over half the survivors. For most, visual screening and full visual assessment was achieved within about 5 days of stroke onset. Crucial information can thus be provided on visual status and its functional significance to the stroke team, patients and carers, enabling early intervention. [ABSTRACT FROM AUTHOR]