Wang N, Sun Y, Zhang H, et al. - An increased risk for the development of atrial fibrillation (AF) is conferred by both current and lifetime night shift exposures, irrespective of genetic AF risk. An increased risk of coronary heart disease (CHD), but neither of stroke nor of heart failure (HF), results due to night shift exposure.

• Cohort study with 283,657 participants in paid employment or self-employed without AF and 276,009 persons free of CHD, stroke, and HF at baseline in the UK Biobank.

• Cox proportional hazard models were applied.

• A significant increasing trend was evident in the risk of incident AF from ‘day workers’, ‘shift but never/rarely night shifts’, and ‘some night shifts’ to ‘usual/permanent night shifts’.

• The highest risk was noted in relation to usual or permanent night shifts.

• Higher AF risk was present in persons working over 10 years and an average 3–8 nights/month frequency of night shift work exposure, than shift workers never working nights.