Workaholics Court Early Heart Attack
Advice: Reduce Workload to 40 Hours or Less, Take Weekends Off
July 12, 2002 -- Long hours at the office, too little sleep, working weekends -- it's a recipe for disaster. In the first study of its kind, a group of Japanese researchers has pinpointed a two- to threefold risk of imminent heart attack among workaholics.
Other studies in the U.S. and Japan back up the findings -- that death from heart disease is greatest among those who burn the midnight oil.
In fact, add weekend work to that formula, and there's a "a profound increase in the risk," writes Ying Liu, a public health researcher at Kyushu University in Fukuaka, Japan. His study appears in this month's issue of Occupational and Environmental Medicine.
In the study, researchers identified admissions of patients admitted for heart attack at 25 different Japanese hospitals. They matched the group with healthy controls who were similar ages and also lived nearby.
All completed a questionnaire detailing their weekly working hours, number of days off, and daily hours of sleep within the past months and over the past year. Details of potential risk factors for heart attack were also obtained, including lifestyle, weight, and conditions such as high blood pressure, high cholesterol, and diabetes.
In both groups, there were men who worked more than 40 hours a week -- which meant they had fewer days off and less sleep -- five hours or less a night.
However, those men hospitalized for a heart attack had big lifestyle differences: They worked significantly more hours; they also got consistently less sleep over the long haul.
All those hours at the office -- including weekend work -- were linked to progressively increased risk of heart attack. Men who worked 60-plus hours a week had double the risk of men working 40 or fewer hours.
Sleep loss also took its toll. Men who got five or fewer hours of sleep on average -- or for at least two nights a week -- had a double, or even triple, risk of heart attack.
Sleep deprivation and lack of rest in the very recent past may act as triggers, authors suggest.
Chronic lack of sleep can increase blood pressure and heart rate while chronic stress may induce abnormalities in heart function, authors say. The combination of the two could increase the activity of nerves in the heart to the point where it triggers a heart attack.
Their advice: Restrict working hours to 40 or less a week. If working extended periods of overtime, make sure you get sufficient sleep and have at least two days of rest a month.