Working Long Hours May Increase Heart Disease Risk

Lack of physical recovery time after working long hours may be to blame, researchers say

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) Working very long work hours can cause family problems and dissatisfaction with your job, but new research suggests it may also hurt your heart.

In a recent study, those who worked the longest hours were most at risk for coronary heart disease.

The researchers said one reason for this raised risk might be that people who work longer hours may have less time to rest and physically recover.

"Try to balance your work and home lives."

"This is a very timely study, as many corporations are requiring their employees to work harder and consequently to log more hours on the job, often in lieu of hiring additional staff," said Sarah Samaan, MD, cardiologist and physician partner at the Baylor Heart Hospital in Plano, Texas. "I see the effects of long working hours and job stress in my patients every day."

Yun-Chul Hong, MD, PhD, of the Department of Preventive Medicine at the Seoul National University College of Medicine in South Korea, and colleagues conducted this study.

The researchers studied 8,350 South Korean adults. They asked them about working hours and their health, performed physical exams and took blood. They then determined the patients' risk for coronary heart disease with the Framingham risk model. This model measures an individual’s 10-year risk for heart disease.

Coronary heart disease is the top killer of men and women in the United States. Heart disease is marked by a buildup of plaque in the arteries (the tubes that bring blood to the heart) and can lead to blood clots, stroke or heart attack.

The average age of the workers in this study was 45.

The more hours a person worked, the more likely he or she was to develop coronary heart disease, the researchers found.

People who worked 61 to 70 hours per week had a 42 percent higher risk for heart disease than people who worked 31 to 40 hours. Those who worked 71 to 80 hours a week had a 63 percent higher risk for heart disease than those who worked 31 to 40. People who worked more than 80 hours per week faced the highest risk — their risk was 94 percent higher than people who worked only 31 to 40 hours a week.

The workers in the study averaged 50.1 hours per week, but 38 percent worked more than 52 hours a week.

The tie between the number of working hours and the 10-year risk for heart disease was more pronounced in women than men, the researchers found.

They suggested some reasons for the risk being so high among those who worked so long. For one, working such long hours may not allow for enough time to physically recover from work, they wrote. It may also mean those people have more work demands or are spending less time on relationships with their families, the authors suggested.

"When most waking hours are taken up by work, it leaves little time for family obligations, and even less for 'optional' activities like exercise or preparing healthy meals," said Dr. Samaan who was not involved in this study.

"Relationships may also suffer, which itself can have negative impacts on health. Poor quality sleep may be another consequence. The end result is a higher risk for hypertension, diabetes and high cholesterol, all of which raise heart attack risk," Dr. Samaan said.

"I always encourage my patients to set aside time for themselves, even if just on the weekend," she said. "Most people can fit in at least 15 minutes of exercise a few days a week. Budget the limited time you have, and don't waste it all watching TV or staring at a computer screen. If changing jobs is an option, consider doing so, but in the current market, that is not always an option."

This study was published Aug. 27 in the American Journal of Industrial Health.

The authors disclosed no funding sources or conflicts of interest.

Review Date: 
September 18, 2014
Last Updated:
September 22, 2014