Night shift work and myocardial infarction in the UK Biobank

Area of Science:

• Occupational Health
• Cardiovascular Epidemiology
• Chronobiology

Background:

• Shift work is prevalent and linked to adverse health outcomes like disrupted circadian rhythms and metabolic changes.
• Previous studies suggest a correlation between shift work and myocardial infarction, but conclusive evidence remains limited.

Purpose of the Study:

• To investigate the association between current and past shift work exposure and the risk of myocardial infarction.
• To analyze the impact of night shift work duration, frequency, and rest day patterns on myocardial infarction risk in a large European workforce.

Main Methods:

• Utilized UK Biobank data from over 500,000 participants with a 12-year follow-up.
• Employed Cox proportional hazard models to assess the relationship between various shift work parameters and myocardial infarction incidence.
• Specifically analyzed night shift workers regarding rest day frequency and myocardial infarction events.

Main Results:

• Night shift work significantly elevated myocardial infarction risk compared to day work, with increased risk for 'some' and 'usual/permanent' night shifts.
• Higher frequency and longer duration of night shifts correlated with a greater risk of myocardial infarction.
• Extended rest days (more than one day) did not appear to reduce the risk of myocardial infarction in night shift workers.

Conclusions:

• Both current and lifetime exposure to night shifts are associated with an increased risk of myocardial infarction.
• The findings indicate that longer rest periods do not offer protection against myocardial infarction for night shift workers.