People who work longer hours are at a heightened risk of developing cardiovascular disease or having a stroke, a study by researchers at University College London has found.
The study of 603,838 people in Europe, Australia and the USA, published in The Lancet, found that people who work 55 hours or more each week had a 13% higher chance of developing coronary heart disease compared with those who worked 35 to 40 hours. This remained consistent even when other factors such as age, cholesterol, smoking, alcohol consumption, and blood pressure were taken into account.
Dr Mike Knapton, associate medical director at the BHF, said: 'More research is needed if we are to understand and treat the biological processes that can lead to an increased risk of stroke and heart disease for people who work long hours. This study highlights to [healthcare professionals] that they need to pay particular attention to cardiovascular risk factors when they advise people who work long hours.'
Long hours were also linked to an increased chance of having a stroke. Those working 55 or more hours each week had a 33% higher risk of having a stroke. The longer people work, the more the risk of a stroke increases. For example, people who worked on average 41 to 48 hours a week had a 10% higher risk of a stroke, while those working 49 to 54 hours had a 27% increased risk.
Dr Knapton added: 'It is plausible that there could be a causal relationship behind the link as sudden death following long working hours is often caused by stroke, due to long and repeated periods of stress, although that was not demonstrated in this study.'