According to the CDC, as much as 9.1 percent of the adult population of the United States suffers from depression at any given time. The Mayo Clinic reports that risk factors for this mood disorder include abuse of alcohol and/or other drugs, experiencing a serious illness or injury, and the use of certain medications, including sleeping pills and some cardiac drugs. Now, a team of Korean researchers says that job stress and lack of sleep can be added to that list.
In an article published in the Annals of Occupational and Environmental Medicine, Dr. Ho-Sung Cho and colleagues at Sunkyunkwan University and Gyeonsang National University describe a close relationship between job stress and depression, as well as sleep deprivation and depression, among women working in the finance, manufacturing, and service industries. The team collected demographic data as well as data on work-related stress, sleep quality, and depression from nearly 5,000 women working at 16 different companies in Korea.
Their findings are striking. Using a 95 percent confidence interval, the likelihood that a study participant from the "high job stress" group suffered from depression was 3.72 times the likelihood that someone from the "low job stress" group. With the same level of confidence, the researchers state that women with poor quality of sleep are 4.30 times as likely to be depressed as women with good quality of sleep.
After removing potentially confounding variables such as age, alcohol consumption, body-mass index (BMI), educational level, and marital status, the predictive values of job stress level and sleep quality level were similarly strong: women with high levels of job stress have an odds ratio (OR) of 3.58 compared to their low-job-stress peers, and women with poor quality of sleep have an OR of 3.81 compared with their better-sleeping peers. Specific factors creating job stress and affecting depression include lack of reward, unreasonable communication, and a hierarchical environment.
What are the implications of these results? Dr. Cho's team believes that undertaking a larger study with a deeper investigation of specific stress- and sleep-related factors will shed more light on the underpinnings of work- and sleep-related depression. The team also recommends that workplaces set "depression management standards," particularly for women.