<p>People who work night shifts are at increased risk of developing an irregular and often abnormally fast heart rhythm called atrial fibrillation (AF), according to a new study led by a team of international researchers. The findings were published in the European Heart Journal. The study is the first to investigate the links between night shift work and AF. Using information from 283,657 people in the UK Biobank database, researchers found that the longer and more frequently people worked night shifts over their lifetimes, the greater their risk of AF. Night shift work was also linked to an increased risk of heart disease, but not to stroke or heart failure. In addition, the researchers led by Professor Yingli Lu, of Shanghai Ninth People's Hospital and Shanghai JiaoTong University School of Medicine, Shanghai, China, and Professor Lu Qi, of Tulane University School of Public Health and Tropical Medicine, New Orleans, USA, investigated whether genetic predisposition to AF could play a role in the increased risk.</p>