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Working overtime: Good for the wallet, but bad for the heart

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Working overtime increases your risk of coronary heart disease (CHD), according to a report published May 12 in the European Heart Journal.

Using data from a study called Whitehall II, which followed 6,014 British civil servants for an average of 11 years between 1991 and 2004, researchers examined the risk of CHD in people who did not work overtime compared to their workaholic office-mates. Those who worked three hours or more extra per day had a 56 percent higher risk of heart-related problems, including angina (chest pain resulting from a temporary lack of blood to the heart) and heart attacks.

"Our findings suggest a link between working long hours and increased CHD risk, but more research is needed before we can be confident that overtime work would cause CHD," said lead author Marianna Virtanen, from the Finnish Institute of Occupational Health, in a prepared statement. The link was independent of several better-known risky behaviors such as smoking, being overweight, having high cholesterol or having a type A personality.

"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," said Virtanen. It’s also possible that the chronic stress associated with working long hours adversely affects metabolic processes, she said.

Roughly half of the study subjects didn’t work overtime. But 21 percent worked one extra hour, 15 percent worked two extra hours, and 10 percent worked three hours or more extra per day.

"At the moment there is no research on whether reduction in overtime work reduces CHD risk. Further research on this topic is therefore needed," said senior author Mika Kivimäki, from University College London, in a prepared statement. Kivimäki plans to investigate whether working long hours predicts changes in lifestyle, mental health and traditional risk factors, such as blood pressure, blood glucose and cholesterol.

It’s unclear whether the findings generalize to blue-collar workers and employees in the private sector, the authors report.

In the journal, the study was accompanied by an editorial written by Gordon McInnes from University of Glasgow Western Infirmary. "If the effect is truly causal, the importance is much greater than commonly recognized," McInnes wrote. "Physicians should be aware of the risks of overtime and take seriously symptoms such as chest pain, monitor and treat recognized cardiovascular risk factors, particularly blood pressure, and advise an appropriate lifestyle modification."

McInnes concluded by quoting the English philosopher Bertrand Russell: "If I were a medical man, I should prescribe a holiday to any patient who considers work important."

Image: iStockphoto/nyul

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  1. 1. Archimedes 5:39 pm 05/11/2010

    In the USA, nurses are routinely required to work 12 hour shifts. The same endangers the health and welfare of both nurses and patients. The Texas Nurses Association recently took an position in opposition to 12 hour shifts asserting that the same unreasonably endangered the health of patients because the same resulted in an increase in medical errors and poor medical and nursing judgement. Physicians, especially physicians in training, are likewise endangering their own health and that of their patients by working long hours. The same long working hours for health care providers should be banned by law because of the aforementioned .

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  2. 2. jtdwyer 7:05 pm 05/11/2010

    Archimedes – You fail to mention how many shifts per week. How is the reader to assess this? If the demand for health care workers is so high, refuse to work overtime, or switch to truck driving – it’s ‘regulated’. Everyone’s own case is special. Besides, this article is about heart disease, not exhaustion and its affect on judgment…

    I required myself to average working 60 hours per week for >25 years. I can’t do that anymore, of course…

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  3. 3. hillsurfer 2:08 pm 05/12/2010

    I’d like to see a definition of "work" included in a study like this. I have had jobs that required swinging a sledgehammer all day, watching meters all night, and currently sit on my butt holding a steering wheel all day (or night). If the jobs mentioned all require sitting at a desk, then it only makes sense that sitting at a desk longer would cause more heart disease. Currently, I stop for regular breaks, usually in rest areas, where I take my dog for a walk. I’m sure this is much better for my heart than standing outside the office smoking a cigarette. I have donuts and coffee for breakfast less than once a month…and so on.

    @jtdwyer – we’re regulated to 70 hours of work in 8 days, no more than 11 hours of driving without a 10 hour break, no more than 14 hours between the start of our day and the end of our driving, though we can work 24 hours past that and nobody cares, as long as we take a 10 hour break after the work, and before we drive.

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  4. 4. jtdwyer 3:38 pm 05/12/2010

    hillsurfer – Yeah, I was trying to be facetious, thus the quoted ‘regulated’. Lot’s of people have to work real hard for their living: some feel like they’re the only ones who suffer. Ask any old farmer about hard work (before the days of subsidies). By the way, all my ‘extra’ hours never earned any overtime pay, but I had work that had to be done.

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