Around half a million Canadian workers experience depression and most of them say the symptoms interfere with their ability to work, according to a new study.
Data from the 2002 Canadian Community Health Survey, which focused on mental health and well-being, show that almost 4% of workers aged 25 to 64 had experienced depression in the 12 months before the survey.
The Health Reports study “Depression and work impairment,” revealed that the workers most prone to depression were those who regularly worked evening or night shifts, along with those employed in sales or service.
Nearly 8 out of 10 (79%) workers who had experienced depression in the year before they were interviewed reported that the symptoms had interfered with their ability to work, at least to some extent. Almost one in five (19%) reported a very severe degree of interference.
Depressed workers reported an average of 32 days in the previous year when their symptoms left them either unable to carry out normal activities or totally unable to work.
This study reinforces other research, which found that several crucial elements of job performance, such as time management, concentration, teamwork and overall output, are particularly vulnerable to depressive symptoms.
Shift workers more likely to be depressed
A number of job-related factors, such as shift work, hours of work, work stress and occupation, were associated with depression.
Men and women who worked evening or night shifts were more likely to be depressed than those who had a regular day-time schedule.
The prevalence of depression was relatively high among workers who spent fewer than 30 hours a week on the job, and lower among those who worked more than 40 hours.
People who described most days at work as stressful were more likely than those reporting less stress to have had a depressive episode in the year before the survey. This is consistent with other research that has shown a relationship between work stress and psychological disorders.
Workers in sales or service and those in white-collar jobs were more likely than blue-collar workers to have experienced depression.
Work impairment more likely among depressed workers
Relatively high percentages of workers who had experienced depression reported specific forms of work impairment. These included reduced activities because of a long-term health condition, at least one mental health disability day in the past two weeks, and absence from work in the previous week.
About 29% of workers who had had a recent episode of depression reported reduced work activities because of a long-term health condition. This was three times the proportion of only 10% among those with no history of depression.
As well, 13% of workers who had experienced depression reported at least one day in the previous two weeks when they had to stay in bed, or cut down on normal activities, or their daily activities took extra effort, because of emotional or mental health or the use of alcohol or drugs.
Only 1% of workers with no history of depression had taken a mental health disability day in the previous two weeks.
Also, 16% of workers who had had a recent depressive episode had been absent from work in the past week, twice the proportion of 7% of those who had never had a depressive episode.
Even when other possible influences were considered, these associations between depression and work impairment persisted.
Impact of depression on job performance can persist
This study also examined, over a two-year period, the association between depression and subsequent work impairment, using longitudinal data from the first five cycles of the National Population Health Survey.
Workers who had been depressed were 1.4 times as likely to report reduced work activities two years later because of a long-term physical or mental health condition, compared with workers who had not had a recent depressive episode.
As well, two years later, workers who had had a depressive episode were 1.8 times as likely to report having taken at least one disability day in the past two weeks.
The article “Depression and work impairment” is included in the latest edition of Health Reports, Vol. 18, no. 1 (82-003-XWE, free), now available from the Publications module of our website.
About Statistics Canada
Statistics Canada produces statistics that help Canadians better understand their country�its population, resources, economy, society and culture. In Canada, providing statistics is a federal responsibility. As Canada�s central statistical agency, Statistics Canada is legislated to serve this function for the whole of Canada and each of the provinces. Visit www.statscan.ca