Some bad news for workers facing stress on the job and elsewhere in their life, suggested by 2 studies published this week: stress may contribute to an increased risk of heart disease and may impair short-term memory.
Workers who encounter substantial demands at work and have little control over their situations have an elevated risk of developing heart disease compared with individuals who don’t have to face such psychological stress in the workplace, according to results of an analysis published in the Lancet yesterday. The researchers examined data for 200 000 Europeans, information compiled from several published and unpublished studies that collected data on reported job demands and cardiovascular disease. They found that such work strain may account for about 3.4% (population attributable risk) of the risk of heart disease in the general population. The good news is that factors that a worker can change have a far greater effect on heart disease, with smoking accounting for 36% of the population attributable risk and physical inactivity accounting for 12% of such risk.
Stress may also impair an individual’s performance, a study published in PLOS Computational Biology suggests. The researchers found that exposure of rats to stress in the form of blasts of sound alter the firing of neurons in the prefrontal cortex. These changes in firing impair the ability of rats to retain short-term memory, hampering their performance in a maze task. Animals under stress completed the task only about 65% of the time compared with 90% of the unstressed rats.
“We’re simultaneously watching dozens of individual neurons firing in the rats’ brains, and under stress the neurons get even more active,” said lead author David Devilbiss, PhD, of the University of Wisconsin. “But what they are not doing is retaining information important to completing the maze. They are reacting to other things, less useful things.”