Michael B. Gravenor

PurposeSecondary prevention of stroke requires effective cardiovascular risk factor (RF) management, including blood pressure control, lipid lowering treatment and antithrombotic therapy to reduce the risk of recurrent stroke. Optimal management of risk factors is challenging in older, frailer people, who also have worse outcomes after a stroke. There is limited evidence evaluating secondary prevention quality and outcomes in frail populations. To understand the trends (and factors associated with inequity) in the provision of RF management we developed the `Evaluation of Population Secondary Prevention Quality and Outcomes Post-Stroke (ESP-QOPS) in Wales' e-cohort. The aims of this project include describing (i) the provision of post-stroke evidence-based risk factor management (ii) trends in frailty and outcomes, and (iii) evaluating the impact of suboptimal risk factor provision on adverse outcomes stratified by frailty status. ParticipantsWe identified 71,696 patients with a first recorded stroke diagnosis in primary or secondary care between 2010-2023 in Wales. Findings to DateThe incidence of stroke gradually increased from 4,968 to 5,391 patients per year between 2010-2023, with 70% of diagnoses made in the secondary care setting. Of diagnoses made in primary care, less than 20% were subsequently admitted to secondary care.

Aims: In patients with diabetes mellitus (DM) and atherosclerotic cardiovascular disease (ASCVD), or without ASCVD (primary prevention), the prescribing of lipid lowering therapy (LLT) is an established treatment strategy endorsed by clinical guidelines. This study aimed to document (i) trends in presentation of DM, (ii) treatment, monitoring and achievement of target low-density lipoprotein cholesterol (LDL-C) in DM with ASCVD, and (iii) ASCVD risk assessment and lipid treatment according to risk in the DM primary prevention setting. Methods and results: A retrospective observational population study including 282 581 DM patients using linked health-care data (2010–23) in Wales. The prevalence of DM (documented DM diagnosis in record prior to the beginning of the year) increased from 133 439 in 2010 to 183 948 in 2023 (6504 to 8200 per 100 000), along with increasing incidence (new diagnosis of DM documented in record during specific year) with 11 074 cases in 2010 (540 per 100 000 per year), increasing to 14 539 in 2023 (648 per 100 000 per year). The proportion of prevalent patients with established ASCVD prescribed LLT decreased from 87.5% to 81.8% (2010–23), testing of LDL-C decreased from 70.3% to 67.1%, and of those with documented lipids 41.0% achieved an LDL-C 20%, only half were prescribed LLT. Conclusion: Increasing incidence and prevalence of DM, together with decreasing quality of risk factor management has the potential to lead to poorer health outcomes in the population if not addressed more effectively.

Aims: European clinical guidelines recommend that patients with atherosclerotic cardiovascular disease (ASCVD), including ischaemic heart disease (IHD), stroke, and peripheral arterial disease (PAD), are prescribed lipid lowering treatment (LLT) and treated to target low-density lipoprotein cholesterol (LDL-C) levels. This study aimed to document trends in ASCVD, including treatment, monitoring, and achievement of target LDL-C. Methods and results: A retrospective observational population study was performed using linked healthcare data (2010–22). Over the study period, the number of patients with ASCVD increased from 181 153 to 207 747 (8882 to 9398 per 100 000). The proportion of patients prescribed LLT decreased from 75.3% in 2010 to 67.1% in 2022; high-intensity statin therapy increased from 9.4 to 25.2%, while non-high-intensity statin therapy decreased from 59.6 to 38.2%. The prescription of high-intensity statin therapy was consistently higher amongst patients with IHD (10.9% in 2010 increasing to 28.0% in 2022) than in patients with stroke (4.7–21.6%) or PAD (3.9–10.6%). The proportion of cases with documented LDL-C decreased from 58.0% in 2010 to 49.3% in 2022. Of those with documented LDL-C in 2022, 44.0% achieved LDL-C < 1.8 mmol/L, including 45.2% of those with IHD, 42.0% of those with stroke, and only 32.8% of those with PAD. Conclusion: Prescription of LLT, including high-intensity statin therapy, documentation of LDL-C, and achievement of target LDL-C levels was relatively low, especially in PAD patients. Although target achievement in ‘tested patients’ increased over time, the proportion of patients undergoing lipid testing declined. More rigorous lipid management requires prioritisation, especially for PAD and stroke patients.

The sudden outbreak of the COVID-19 pandemic presented governments, policy makers and health services with an unprecedented challenge of taking real-time decisions that could keep the disease under control with non-pharmaceutical interventions, while at the same time limit as much as possible severe consequences of a very strict lockdown. Mathematical modelling has proved to be a crucial element for informing those decisions. Here we report on the rapid development and application of the Swansea Model, a mathematical model of disease spread in real time, to inform policy decisions during the COVID-19 pandemic in Wales.

In patients with non-valvular atrial fibrillation (NVAF) prescribed warfarin, the association between guideline defined international normalised ratio (INR) control and adverse outcomes in unknown. We aimed to (i) determine stroke and systemic embolism (SSE) and bleeding events in NVAF patients prescribed warfarin; and (ii) estimate the increased risk of these adverse events associated with poor INR control in this population. Individual-level population-scale linked patient data were used to investigate the association between INR control and both SSE and bleeding events using (i) the National Institute for Health and Care Excellence (NICE) criteria of poor INR control [time in therapeutic range (TTR) 8]. A total of 35 891 patients were included for SSE and 35 035 for bleeding outcome analyses. Mean CHA₂DS₂-VASc score was 3.5 (SD = 1.7), and the mean follow up was 4.3 years for both analyses. Mean TTR was 71.9%, with 34% of time spent in poor INR control according to NICE criteria. SSE and bleeding event rates (per 100 patient years) were 1.01 (95%CI 0.95–1.08) and 3.4 (95%CI 3.3–3.5), respectively, during adequate INR control, rising to 1.82 (95%CI 1.70–1.94) and 4.8 (95% CI 4.6–5.0) during poor INR control. Poor INR control was independently associated with increased risk of both SSE [HR = 1.69 (95%CI = 1.54–1.86), P < 0.001] and bleeding [HR = 1.40 (95%CI 1.33–1.48), P < 0.001] in Cox-multivariable models. Guideline-defined poor INR control is associated with significantly higher SSE and bleeding event rates, independent of recognised risk factors for stroke or bleeding.

In the context of the WHO’s measles and rubella elimination targets and European Immunization Agenda 2030, this large cross-sectional study aimed to identify inequalities in measles vaccination coverage in Wales, UK. The vaccination status of individuals aged 2 to 25 years of age, alive and resident in Wales as of 31 August 2021, was ascertained through linkage of the National Community Child Health Database and primary care data. A series of predictor variables were derived from five national datasets and all analysis was carried out in the Secure Anonymised Information Linkage Databank at Swansea University. In these 648,895 individuals, coverage of the first dose of measles-containing vaccine (due at 12–13 months of age) was 97.1%, and coverage of the second dose (due at 3 years and 4 months) in 4 to 25-year-olds was 93.8%. In multivariable analysis, excluding 0.7% with known refusal, the strongest association with being unvaccinated was birth order (families with six or more children) and being born outside of the UK. Living in a deprived area, being eligible for free school meals, a lower level of maternal education, and having a recorded language other than English or Welsh were also associated with lower coverage. Some of these factors may also be associated with refusal. This knowledge can be used to target future interventions and prioritise areas for catch up in a time of limited resource.

Background: dementia may increase care home residents’ risk of COVID-19, but there is a lack of evidence on this effect and on interactions with individual and care home-level factors. Methods: we created a national cross-sectional retrospective cohort of care home residents in Wales for 1 September to 31 December 2020. Risk factors were analysed using multi-level logistic regression to model the likelihood of SARS-CoV-2 infection and mortality. Results: the cohort included 9,571 individuals in 673 homes. Dementia was diagnosed in 5,647 individuals (59%); 1,488 (15.5%) individuals tested positive for SARS-CoV-2. We estimated the effects of age, dementia, frailty, care home size, proportion of residents with dementia, nursing and dementia services, communal space and region. The final model included the proportion of residents with dementia (OR for positive test 4.54 (95% CIs 1.55–13.27) where 75% of residents had dementia compared to no residents with dementia) and frailty (OR 1.29 (95% CIs 1.05–1.59) for severe frailty compared with no frailty). Analysis suggested 76% of the variation was due to setting rather than individual factors. Additional analysis suggested severe frailty and proportion of residents with dementia was associated with all-cause mortality, as was dementia diagnosis. Mortality analyses were challenging to interpret. Discussion: whilst individual frailty increased the risk of COVID-19 infection, dementia was a risk factor at care home but not individual level. These findings suggest whole-setting interventions, particularly in homes with high proportions of residents with dementia and including those with low/no individual risk factors may reduce the impact of COVID-19.

Background: defining features of the COVID-19 pandemic in many countries were the tragic extent to which care home residents were affected and the difficulty in preventing the introduction and subsequent spread of infection. Management of risk in care homes requires good evidence on the most important transmission pathways. One hypothesised route at the start of the pandemic, prior to widespread testing, was the transfer of patients from hospitals that were experiencing high levels of nosocomial events. Methods: we tested the hypothesis that hospital discharge events increased the intensity of care home cases using a national individually linked health record cohort in Wales, UK. We monitored 186,772 hospital discharge events over the period from March to July 2020, tracking individuals to 923 care homes and recording the daily case rate in the homes populated by 15,772 residents. We estimated the risk of an increase in case rates following exposure to a hospital discharge using multi-level hierarchical logistic regression and a novel stochastic Hawkes process outbreak model. Findings: in regression analysis, after adjusting for care home size, we found no significant association between hospital discharge and subsequent increases in care home case numbers (odds ratio: 0.99, 95% CI: 0.82, 1.90). Risk factors for increased cases included care home size, care home resident density and provision of nursing care. Using our outbreak model, we found a significant effect of hospital discharge on the subsequent intensity of cases. However, the effect was small and considerably less than the effect of care home size, suggesting the highest risk of introduction came from interaction with the community. We estimated that approximately 1.8% of hospital discharged patients may have been infected. Interpretation: there is growing evidence in the UK that the risk of transfer of COVID-19 from the high-risk hospital setting to the high-risk care home setting during the early stages of the pandemic was relatively small. Although access to testing was limited to initial symptomatic cases in each care home at this time, our results suggest that reduced numbers of discharges, selection of patients and action taken within care homes following transfer all may have contributed to the mitigation. The precise key transmission routes from the community remain to be quantified.