Health Citing: Are Your Work Hours Increasing Your Risk For Heart Disease?

Interesting results were recently published that linked hard work to heart disease. “Hard work” was defined as averaging greater than 11 hours of work a day compared to a more typical 7-8 hour work day. The authors retrieved data from the Whitehall II study in which over 7000 civil service workers in the London area were followed for over 12 years. During follow-up, 192 (2.7 per cent) of participants developed coronary heart disease (impaired blood supply to the heart). Those participants who worked greater than 11 hours/day had a 67 per cent higher risk of developing heart disease, even after adjusting for baseline differences in known cardiac risk factors. The authors concluded that factoring the workday into an overall risk assessment that includes blood pressure, blood glucose, smoking history, etc leads to a slight improvement in the ability to predict subsequent heart disease.

There are, however, some valid criticisms of this study. For example, there was no description of the type of work that was involved. Does 11 hours of “office” work lead to the same risk as 11 hours of heavy manual labour? Of course, based upon the population studied (civil servant workers), one would suspect that the typical work day was not particularly strenuous (but may certainly be stressful). In addition, the baseline risk of this cohort was very low (thus the low overall incidence of heart disease during follow up) and the study cannot determine the impact of working hours on patients at high risk for developing heart disease.

So what’s the take home message? If you spend more than 11 hours per day at the office, be careful to modify other potential risk factors for heart disease. Namely, refrain from smoking, eat a healthy diet and pursue regular physical exercise. As a surgeon who routinely spends more than 12 hours a day in the hospital, these findings are particularly relevant. But as the weather turns warmer, I intend to leave the office earlier  and get out on the golf course. In doing this I am able to say that I’m lowering my risk for heart disease.