Overtime is bad for your heart
Major survey of UK civil servants shows 60% higher risk of suffering heart conditions when working longer hours
12th May 2010 - Working overtime is bad for the heart according to results from a long- running study following more than 10,000 civil servants in London, known as the Whitehall II study.
The research, which is published online today in the European Heart Journal found that, compared with people who did not work overtime, people who worked three or more hours (but not one to two hours) longer than a normal, seven-hour day had a 60% higher risk of heart-related problems such as death due to heart disease, non-fatal heart attacks and angina.
Dr Marianna Virtanen, an epidemiologist at the Finnish Institute of Occupational Health, Helsinki and University College London (UCL), said in a news release: “The association between long hours and coronary heart disease was independent of a range of risk factors that we measured at the start of the study, such as smoking, being overweight or having high cholesterol.”
The researchers say there could be a number of possible explanations for this association between overtime and heart disease. Their results showed that working overtime was related to type A behaviour pattern (people with type A behaviour tend to be aggressive, competitive, tense, time-conscious and generally hostile), psychological distress manifested by depression and anxiety, and possibly with not enough sleep, or not enough time to unwind before going to sleep.
Other possible explanations include: high blood pressure that is associated with work-related stress but is ‘hidden’ because it doesn’t necessarily show up during medical check-ups; ‘sickness presenteeism’ whereby employees who work overtime are more likely to work while ill, ignore symptoms of ill health and not seek medical help; and, finally, it is possible that people in jobs where they have more freedom over their work-related decisions may have a lower risk of coronary heart disease despite working overtime.
However, Virtanen says that their findings were independent of all of the above factors, and so they could not necessarily provide the full explanation as to why overtime was associated with the higher risk of heart disease.
In addition, she says: “We did not measure whether subsequent changes in these factors during the follow-up period altered the association. One plausible explanation for the increased risk could be that adverse lifestyle or risk factor changes are more common among those who work excessive hours compared with those working normal hours.
“Another possibility is that the chronic experience of stress (often associated with working long hours) adversely affects metabolic processes. It is important that these hypotheses should be examined in detail in the future.”
Look after your heart at work
Cathy Ross, Senior Cardiac Nurse at the British Heart Foundation, which part funded the study, says in an e-mail: “The researchers suggest a number of reasons - ‘hidden’ high blood pressure, reduced sleeping hours and psychological stress. These may affect the mechanisms that cause heart disease, but it could simply be that working long hours means we’ve less time to look after ourselves.
“If we’re stuck in the office we’ve less time to relax, get a good night’s sleep, and take enough physical activity, all of which have been found to help reduce stress levels and protect against heart disease.
“Until researchers understand how our working lives can affect the risk to our heart health there are simple ways to look after your heart health at work, like taking a brisk walk at lunch, taking the stairs instead of the lift, or by swapping that biscuit for a piece of fruit.”