Long hours can affect heart health, study finds
Overtime at a desk job linked to hidden high blood pressure, study’s author says
Working long hours behind a desk might raise the risk of undiagnosed high blood pressure, or hypertension, even when readings in a doctor’s office are normal, a new study suggests.
In an analysis of data from more than 3,500 white collar workers, researchers found those who spent long hours on the job were 66 per cent more likely to have sustained hypertension and 70 per cent more likely to have so-called masked hypertension — blood pressure that is normal in the doctor’s office, but high at other times.
“People should be aware that long work hours might affect their heart health, and if they’re working long hours, they should ask their doctors about checking their blood pressure over time with a wearable monitor,” the study’s lead author, Xavier Trudel, an assistant professor in social and preventive medicine at Laval University in Quebec, said in a statement.
“Masked hypertension ... is associated, in the long term, with an increased risk of developing cardiovascular disease,” Trudel said. “We’ve previously shown that over five years, about one in five people with masked hypertension never showed high blood pressure in a clinical setting, potentially delaying diagnosis and treatment.”
The authors did not respond to a request for comment.
To take a closer look at the possible impact of long work hours on blood pressure, Trudel and his colleagues recruited 3,547 white collar employees at three public institutions in Quebec that mainly provide insurance coverage.
Trudel and colleagues checked volunteers’ blood pressure during the first year, in Year 3, and again in Year 5. To simulate a doctor’s office reading, the researchers used an office at the workplace and measured each volunteer’s blood pressure three times on one morning. For the rest of that workday, the volunteers wore a blood pressure monitoring device, which took readings every 15 minutes, collecting a minimum of 20 additional blood pressure readings for that day.
The researchers defined hypertension as 140/90 mm/hg or higher during the resting reading in the simulated clinic visit, and 135/85 mm/hg measured during the workday. Overall, 18.7 per cent of the volunteers had sustained hypertension, including employees who were already taking antihypertensive medications, and 13.5 per cent had masked hypertension and were not receiving treatment for high blood pressure.
When the researchers analyzed the blood pressure data accounting for factors that might affect the risk of hypertension, such as job strain, age, gender, education level, occupation, smoking and body mass index (BMI), they found long hours significantly raised the risk of high blood pressure.
Volunteers working 49 or more hours per week were 70 per cent more likely to exhibit masked hypertension, while those working 41 to 48 hours per week were 51 per cent more likely to have masked hypertension, compared to colleagues who spent less time at the office.
Similarly, volunteers who worked 49 or more hours per week were 66 per cent more likely to have sustained hypertension, while those working 41 to 48 hours per week were 33 per cent more likely to have sustained hypertension compared to colleagues who worked fewer hours, the researchers reported in Hypertension.
The new study was intriguing to Dr. Matthew Muldoon, a professor of medicine at the University of Pittsburgh, Pennsylvania, and director of the hypertension program at the UPMC Heart and Vascular Institute.
Muldoon suspects the increased risk of hypertension might be related to long hours sitting.
“And certainly, it’s possible that people who work long hours are not as active,” he said.