August may be the cruellest month for brain injuries in Ontario's construction industry, but a new study shows October is not far behind.
"We thought it was important to track these injuries month by month," says Dr. Angela Colantonio, a senior scientist at Toronto Rehab and co-author of the study published this week in the journal Brain Injury.
Few academic studies have looked at brain injury among construction workers. Yet the construction industry - with approximately 400,000 workers in Ontario alone - is known to have a high rate of serious brain injury.
Traumatic brain injury is a leading cause of death and disability. TBI can profoundly affect a person's cognitive skills, memory, language and behaviour, as well as their independence, work life, and ability to participate fully in the community.
The new study used data from the Ontario Workplace Safety and Insurance Board on 218 cases of non-fatal brain injury which resulted in days off work in 2004-2005.
The authors weren't surprised to find the highest number of brain injuries in the busy construction month of August, while December had the lowest number. But they didn't expect to find a second peak of injuries in October. This may reflect a surge in work to complete projects prior to the winter months. Contributing factors, they speculate, could be shorter days to work, less light, and more adverse weather conditions. The authors want to do further study to find out if this seasonal pattern holds for other years.
Their study also begins to raise questions about the time of day when many construction-related brain injuries occur. It identifies two peaks during the day: the hour before and the hours after lunch.
"Most of us know that lethargic feeling that hits just before or after lunch at work: our energy dips, it's hard to focus but we have a job to finish," says Dr. Colantonio. Other factors may also be distracting workers in anticipation of, or during, their lunch break - and affecting their attention on the job. "For construction workers, this could have devastating consequences."
Among other findings, younger workers were much more likely to experience brain injuries in the morning, while older workers were more likely to suffer such injuries in late afternoon.
"More injuries in the morning for younger workers can potentially be explained by shifting sleep cycles in young adults favouring later times to go to sleep and get up, as well as overall shorter hours of sleep," the authors suggest. Fatigue may also be contributing to injuries experienced by older workers in the afternoon. Falls were much more likely to be the cause of injury among older workers.
"These results provide valuable information for preventing these injuries," says Dr. Colantonio. "They can be incorporated into prevention strategies."
Doug McVittie, assistant general manager and director of operations for the Construction Safety Association of Ontario (CSAO), says his group will circulate the findings to construction companies across the province, as well as labour and management health and safety committees. The results will also be shared with CSAO staff members who provide training and safety seminars for construction workers.
"Construction workers work in circumstances which are in some cases inherently risky; we're working at heights, we've got temporary and incomplete structures, moving equipment, moving materials," says McVittie, a study co-author. "Our association is interested in working to enhance the understanding of construction risks, and help with getting a better appreciation for the prevention message out there in all sectors."
Says Dr. Colantonio: "Our findings have drawn attention to areas that, with more study, could actually expose some of the underlying causes of work-related brain injury." Dr. Colantonio holds the Saunderson Family Chair in Acquired Brain Injury Research at Toronto Rehab. She is also a Professor in the Department of Occupational Science and Occupational Therapy at the University of Toronto.
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