This population-based record-linkage study identified first-ever stroke events in adults in England between 1 April 2018 and 31 March 2024. Multiple overlapping sources were used to capture events: primary care extraction, hospital admissions data, death certificates, and records from the national stroke audit (SSNAP). The analysis included 643,885 incident strokes in three consecutive two-year periods: 2018–2020 (n = 206,290), 2020–2022 (n = 211,420), and 2022–2024 (n = 226,175).
The investigators calculated standardised age-specific stroke incidence for two age categories (<55 years and ≥55 years) and compared rates across three time periods: pre COVID-19 pandemic (2018–2020), COVID-19 pandemic (2020–2022), and post COVID-19 pandemic (2022–2024). Incidence rate ratios (IRRs) were used to compare time periods. The Relative Temporal Trend Ratio (RTTR) quantified divergence between younger and older age groups over time. Analyses were stratified by sex, ethnicity, socioeconomic deprivation, region, and stroke subtype.
Stroke incidence among adults aged <55 years increased significantly during the pandemic compared with the pre-pandemic period (2020–2022 vs 2018–2020: IRR = 1.07, 95% CI 1.05–1.09, p < 0.001). The upward trend persisted into the post-pandemic period (2022–2024 vs 2020–2022: IRR = 1.04, 95% CI 1.02–1.06, p < 0.001). The rise at younger ages was observed across sexes, deprivation groups, regions, and stroke subtypes.
In contrast, stroke incidence among adults aged ≥55 years was stable during the pandemic (IRR = 0.99, 95% CI 0.99–1.00, p = 0.06) but increased after the pandemic (2022–2024 vs 2020–2022: IRR = 1.04, 95% CI 1.03–1.04, p < 0.001). Thus, the temporal pattern differed by age group, with an earlier and sustained less favourable trend at younger ages.
The study quantified the growing age divergence using the RTTR. The divergence — reflecting a comparatively worse trend at younger ages — widened significantly during the pandemic (RTTR = 1.07, 95% CI 1.05–1.08, p < 0.001). No significant reversal in this divergence was observed after the pandemic (RTTR change post-pandemic was not statistically significant).
The increased incidence at younger ages was consistent by sex, deprivation, region, and stroke subtype. The rise was most pronounced among ethnic minority groups during the pandemic: Black individuals had IRR = 1.13 (95% CI 1.05–1.21, p = 0.0005) and Asian individuals had IRR = 1.26 (95% CI 1.20–1.33, p < 0.001) for 2020–2022 versus 2018–2020. These subgroup findings indicate heterogeneous impacts across demographic groups.
Overall recorded prevalence of modifiable stroke risk factors — hypertension, diabetes, atrial fibrillation, and hyperlipidaemia — remained largely unchanged during and after the pandemic for both age groups. However, among adults <55 years there was a notable increase in the frequency of previously undiagnosed premorbid hypertension and diabetes during the pandemic: hypertension risk ratio (RR) = 1.07 (95% CI 1.02–1.13) and diabetes RR = 1.22 (95% CI 1.08–1.37). The increase in undiagnosed conditions was particularly evident in ethnic minority groups and had not improved by the post-pandemic period.
The authors highlight key limitations arising from reliance on routinely collected data. Data lacked the granularity to explore mechanistic drivers of the observed trends. While linkage across multiple data sources aimed to reduce bias related to changes in patient behaviour and service use, routine data remain limited in detail on factors such as individual SARS-CoV-2 infection status, vaccination details, lifestyle changes, or reasons for missed primary care screening.
From 2018 to 2024 in England, the age-specific divergence in stroke incidence has continued and widened during the COVID-19 pandemic, driven by increasing incidence among adults <55 years and particularly affecting ethnic minority groups. Concurrently, there was evidence of reduced identification and diagnosis of premorbid hypertension and diabetes in younger adults during the pandemic, suggesting missed opportunities in primary care. The authors conclude that urgent action is needed to restore and strengthen cardiovascular risk factor screening and diagnosis in primary care and to monitor ongoing age-specific trends in stroke incidence. The study underscores the value of multi-source record linkage for surveillance but notes the need for data with greater clinical detail to clarify causal mechanisms.