Women with low job control at work are twice as likely to develop diabetes compared to women with high job control, according to a nine-year study by researchers at the Institute for Work & Health and the Institute for Clinical Evaluative Sciences (ICES).
Published in the September issue of Occupational Medicine (vol. 62, no. 6, pp. 413-419), the study confirmed that high body weight was the principle risk factor for the development of diabetes among working-age adults in Canada. What was surprising in the study was the observation that the proportion of cases of diabetes among women that could potentially be attributed to low job control was higher than that for behaviours such as smoking, drinking, lack of exercise and not eating fruits and vegetables. Low job control was not associated with the incidence of diabetes among men.
The study suggests job control—a person’s ability to influence how they meet the demands of their job and how they use their skills—could potentially be an important modifiable risk factor to reduce the incidence of diabetes among women. With additional research from intervention studies, we may learn that improved job control for women, such as providing autonomy over the way they do their jobs, could be considered as part of a comprehensive diabetes prevention strategy, says IWH Scientist Dr. Peter Smith, lead author of the study.
The Canadian Diabetes Association agrees. Given the findings of this study, it is recommended that job control along with workplace wellness programs be evaluated in workplaces as a strategy to lower the risk of diabetes in women, says Dr. Janet Hux, the association’s chief scientific advisor.
Prevalence of diabetes growing
Diabetes is a growing public health concern. Over nine million Canadians are living with diabetes or pre-diabetes (i.e. having blood glucose levels that are higher than normal, but not high enough to indicate diabetes). In Ontario, the prevalence of diabetes almost doubled between 1995 and 2005.
And yet, the relationship between work stress/psychosocial work conditions and diabetes has not been well examined by researchers to date. “There is a strong body of work that has established a relationship between the psychosocial work environment and high blood pressure and heart disease, but fewer studies examining work stress and the risk of diabetes,” says Smith.
Large group followed for nine years
The study used a representative sample of the Ontario population drawn from the 2000-2001 Canadian Community Health Survey (CCHS). For nine years, the study followed 7,443 working-age adults actively employed (but not self-employed) on the date of the survey who had no previous diagnosis of diabetes. The survey provided information on participants’ health behaviours such as smoking, physical activity, drinking, and fruit and vegetable consumption. It also provided information on their psychosocial work environment, including job control, psychological demands and social support, which was collected through an abbreviated Job Content Questionnaire included in the CCHS.
This information was linked to the Ontario Health Insurance Plan (OHIP) database for physician services and the Canadian Institute for Health Information Discharge Abstract Database (CIHI-DAD) for hospital admissions. This allowed researchers to detect new cases of diabetes among the sample during the nine-year follow-up period.
Study found increased risk for women
Researchers found that low levels of job control were associated with an increased risk of diabetes among women. After taking a wide range of factors into account—including age, ethnicity, body mass index, health behaviours (as mentioned above) and more—women with low job control at work were still 2.04 times more likely to develop diabetes than women with high job control. In all, the proportion of cases of diabetes among women that could potentially be attributed to low job control was 19 per cent—higher than that for other health behaviours such as smoking, drinking, lack of physical activity and poor eating habits, but lower than that for obesity, to which 42 per cent of cases could be attributed.
The two primary pathways linking high psychosocial work stress to diabetes risk are: (1) disruptions to neuroendocrine and immune system functioning, and increased or prolonged cortisol and sympathetic hormone release, in reaction to stress; and (2) changes in health behaviour patterns, particularly those related to diet and energy expenditure, possibly as coping mechanisms.
To read the full study, see the open access version of the paper at: www.occmed.oxfordjournals.org/content/62/6/413.full.