The association of night shift work with the risk of acute ischemic cerebrovascular syndrome: a longitudinal study of 204,261 UK Biobank participants

Clinical Snapshot

Key Findings

• P Value: P = 0.019

• Effect Size: HR 1.118 for irregular shift work vs non-shift work

• Primary Outcome: Acute ischemic cerebrovascular syndrome (AICS)

• Nnt Or Sensitivity: 11.8% increased hazard for irregular shift workers

• Confidence Interval: 95% CI 1.019-1.227

Clinical Application

Findings applicable to occupational health screening and workplace health policies Relevant to Australian shift workers across healthcare, mining, and service industries. Could inform Safe Work Australia guidelines and workplace health assessments under PBS item numbers for cardiovascular risk stratification Working-age adults in shift work occupations, particularly those with irregular schedules

Abstract

BACKGROUND: Shift work is highly prevalent globally, yet evidence linking it to ischemic cerebrovascular disease remains inconsistent. Existing studies are limited by unsystematic quantification of night shift exposure and outcome definitions failing to capture the clinical continuum of ischemic events. We performed a large prospective cohort study using refined shift pattern classification and acute ischemic cerebrovascular syndrome (AICS) as the primary end point to enable a robust evaluation of the association between shift patterns and ischemic cerebrovascular disease. METHODS: 204,261 participants with employment information from the UK Biobank were included. Cox proportional hazards regression was used to assess associations between current shift work and AICS risk, with cross-classification by shift status and job duration. We further quantified average lifetime night shift frequency and cumulative duration among participants with complete occupational histories. Transient ischemic attack (TIA) and ischemic stroke (IS) were analyzed separately to identify the main driver of AICS and potential heterogeneity. RESULTS: During a median follow-up exceeding 14 years, irregular shift work was significantly associated with elevated AICS risk (HR 1.118, 95% CI 1.019-1.227, P = 0.019), while always night shift work was not (HR 0.904, 95% CI 0.707-1.157, P = 0.423). AICS risk was driven by irregular shift patterns rather than duration. Lifetime night shift frequency and duration showed significant dose-response relationships with AICS. CONCLUSIONS: Irregular shift work increases AICS risk relative to non-shift work, and lifetime night shift exposure exhibits a clear dose-response effect. IS constitutes the primary driver of the composite AICS end point.

References

1. 1.Huang, Y., Tan, M. H., Wang, G., Liang, S., Lyu, J., & Huang, L. (2026). The association of night shift work with the risk of acute ischemic cerebrovascular syndrome: a longitudinal study of 204,261 UK Biobank participants. Journal of Neurology. https://doi.org/10.3389/fnagi.2023.1134187