Washington: It is workplace tensions - more than longer hours or night shifts - that follow employees home and interfere with their sleep, according to a study. The study analysed two national surveys of 2,300 adults who were followed up to a decade. Over that time, roughly half the respondents said they had trouble sleeping.

"Together, work and sleep take up about two-thirds of every weekday," said University of Michigan (U-M) sociologist Sarah Burgard. "But until now, very little research has focussed on the connections between work and sleep".

Previous research has shown that lack of sleep can have serious consequences, ranging from traffic accidents to health problems, chronic disease and mortality.

According to the new study, respondents who were upset at work on a frequent basis, or had on-going personal conflicts with bosses or co-workers, were about 1.7 times more likely than others to develop sleep problems.

"Massive changes over the past half-century have reshaped the workplace, with major implications for sleep," Burgard said. "For many workers, psychological stress has replaced physical hazards."

Burgard also explored how work-family conflict, gender, education and job status affected the relationship between work and sleep.

As women have entered the labour force in large numbers, dual-earner households and single-parent families have made the time-crunch a major factor, Burgard said.

Respondents with children under the age of three were about 2.2 times as likely to report poor sleep quality, but having young children did not explain the association between hassles at work and sleep quality.

That's the conclusion of a University of Michigan study presented April 17 at the annual meeting of the Population Association of America. IANS