PT - JOURNAL ARTICLE AU - Robert J Maidstone AU - James Turner AU - Celine Vetter AU - Hassan S Dashti AU - Richa Saxena AU - Frank A J L Scheer AU - Steven A Shea AU - Simon D Kyle AU - Deborah A Lawlor AU - Andrew S I Loudon AU - John F Blaikley AU - Martin K Rutter AU - David W Ray AU - Hannah Jane Durrington TI - Night shift work is associated with an increased risk of asthma AID - 10.1136/thoraxjnl-2020-215218 DP - 2021 Jan 01 TA - Thorax PG - 53--60 VI - 76 IP - 1 4099 - http://thorax.bmj.com/content/76/1/53.short 4100 - http://thorax.bmj.com/content/76/1/53.full SO - Thorax2021 Jan 01; 76 AB - Introduction Shift work causes misalignment between internal circadian time and the external light/dark cycle and is associated with metabolic disorders and cancer. Approximately 20% of the working population in industrialised countries work permanent or rotating night shifts, exposing this large population to the risk of circadian misalignment-driven disease. Analysis of the impact of shift work on chronic inflammatory diseases is lacking. We investigated the association between shift work and asthma.Methods We describe the cross-sectional relationship between shift work and prevalent asthma in >280000 UK Biobank participants, making adjustments for major confounding factors (smoking history, ethnicity, socioeconomic status, physical activity, body mass index). We also investigated chronotype.Results Compared with day workers, ‘permanent’ night shift workers had a higher likelihood of moderate-severe asthma (OR 1.23 (95% CI 1.03 to 1.46)). Individuals doing any type of shift work had higher adjusted odds of wheeze/whistling in the chest. Shift workers who never or rarely worked on nights and people working permanent nights had a higher adjusted likelihood of having reduced lung function (FEV1 <80% predicted). We found an increase in the risk of moderate-severe asthma in individuals with extreme chronotypes (morning, OR 1.55 (95% CI 1.06 to 2.27) or evening, OR 1.31 (95%CI 1.22 to 1.40)).Conclusions The public health implications of these findings are far-reaching due to the high prevalence and co-occurrence of both asthma and shift work. Future longitudinal follow-up studies are needed to determine if modifying shift work schedules to take into account chronotype might present a public health measure to reduce the risk of developing inflammatory diseases such as asthma.All data relevant to the study are included in the article or uploaded as supplementary information. All data is available on request from the first or corresponding author and the codes used to analyse the data.