Before you volunteer to work overtime for the third week this month, you may want to consider the impact of those long hours on your heart. According to a new study from the University of Texas Health Science Center, long office hours could put a strain on the heart, raising the risk of cardiovascular disease.

Published online in the Journal of Occupational and Environmental Medicine, the study looked at data from more than 1,900 people aged 18 and older between 1986 and 2011. The UT researchers collected their data from the Panel Study of Income Dynamics, a longitudinal survey going back to 1968 that’s representative of United States families and individuals. The team specifically looked for a relationship between work hours and cardiovascular disease (CVD) diagnoses.

They found that hard work may not actually pay off in the end — not for people’s health, at least. About 43 percent of study participants had been diagnosed with a CVD-related problem, such as angina, coronary artery disease, heart failure, heart attack, high blood pressure, or stroke, UPI reported.

"This study provides specific evidence on long work hours and an increase [in] the risk of CVD, thereby providing a foundation for CVD prevention efforts focused on work schedule practices, which may reduce the risk of CVD for millions of working Americans," said study author Sadie Conway, according to UPI.  

CVD, more commonly known as heart disease, is an all-encompassing term for various heart problems, many of which stem from the buildup of plaque in artery walls. This buildup, the American Heart Association says, can narrow the arteries and make it harder for blood to flow through. At worst, the plaques can cause heart attacks or stroke when the blood flow is stopped completely. According to the World Health Organization, CVD accounts for about 31 percent of all worldwide deaths, killing 17.5 million people each year — heart attacks and stroke are the main culprits.

The UT study isn’t the first to find a link between poor heart health and long hours at work. A 2015 study found that having a high-stress job increased people’s risk of ischemic stroke by 22 percent, especially among women. High-stress jobs were defined as requiring a lot of effort without giving the employee control over their work, and included nurses and waitresses.

Although the 2015 study found a link between stress and heart health, its authors said the stress may have caused participants to make poor lifestyle choices, including eating a poor diet, smoking, and being physically inactive. The recent study, however, found that working more than 45 hours per week for at least 10 years was its own factor for heart disease, independent of the aforementioned lifestyle choices.  

While the results may be discouraging since most of us need to work to get by, there is some good news: the same heart problems did not extend to those who only worked part-time.

Source: Conway S, Pompeii L, Roberts RE, Follis J, Gimeno D. Dose–Response Relation Between Work Hours and Cardiovascular Disease Risk: Findings From the Panel Study of Income Dynamics. JOEM . 2016