Two-year study finds health-care use by workers with mild traumatic brain injury not back at pre-injury level
People who sustain head injuries such as concussions might not take long to get back to work, but that doesn’t necessarily mean they’re quick to recover. According to a new study, workers who report a mild traumatic brain injury still need additional medical attention two years after the initial injury.
The study, published earlier this year in the Archives of Physical Medicine and Rehabilitation, looked at how much health-care services a cohort of Ontario workers accessed after they made workers’ compensation claims for a mild-traumatic brain injury (MTBI).
We found that health-care utilization did not return back to baseline levels two years after the initial injury, says study lead author Dr. Vicki Kristman, an associate scientist at the Institute for Work & Health (IWH) and assistant professor in the Department of Health Sciences at Lakehead University.
We know from past research that recovery from mild traumatic brain injury is generally quite quick, and people are usually back to work within a couple of weeks, adds Kristman.
We had thought that when most people returned to work, they weren’t using health-care services anymore. So this was a surprise.
One in 10 off work for up to two years
Mild traumatic brain injury is a common type of injury resulting from falls and traffic collisions. According to an earlier study by Kristman, about six out of every 1,000 lost-time claims made to Ontario’s workers’ compensation agency, the Workplace Safety and Insurance Board (WSIB), are for MTBI. The vast majority (87 per cent) of MTBI lost-time claims are for one-time periods of missed work, with the median length being 11 days. However, in five per cent of the cases, the time off due to injury lasts up to two years.
In this latest study, the team found that, as expected, health-care use peaked in the first four weeks post-injury, to 400 per cent higher than the level of health-care use before the injury. Between the fifth and the 12th week after a claim has been filed, the health-care usage is about 180 per cent higher than it was prior to the injury.
By the end of the two-year study period, health-care use was still about 10-per-cent higher than before the injury—though mostly due to the needs of a small subset of workers. The increased use of medical services was most notable among those workers who had accessed health-care services the least before they were injured. These infrequent users of health care (pre-injury) experienced a 125-per-cent increase in medical visits and treatments two years after getting hurt with MTBI.
Learning from OHIP and claims data
To conduct the study, the researchers gathered data from the WSIB and the Ontario Health Insurance Plan (OHIP). They compiled a sample of all who made a workers’ compensation lost-time claim for MTBI in 1997 and 1998 (but excluding anyone who had made a MBTI claim prior to that two-year period). Also, claimants whose OHIP data could not be retrieved were excluded. The final sample included 728 workers.
The researchers relied on both WSIB and OHIP records to gather data on the dates and types of health-care services that the injured workers accessed. (To protect confidentiality, the Ontario Ministry of Health and Long Term Care provided OHIP data with all identifying information removed.) The team then compiled a database of all health-care services used by the claimants in the year before the injury, which served as the baseline level for comparison purposes, as well as in the two years after.
Comparing the types of medical services accessed before and after the head injury, the study found a sharp rise in radiological and neurological services in the first four weeks (a rise of more than 900 per cent). By the six-month mark, the researchers saw a drop in the use of hospital services, as well as services by physiotherapists, chiropractors and general practitioners. That suggested to the research team that treatment ended within six months of the injury for most patients.
In the second year after the claim was filed, the types of medical services accessed the most were related to three types of problems: accidents, poisoning and violence; diseases of the nervous system; and mental disorders.
Research has shown increased likelihood of depression after a concussion, so that could be behind the data for mental disorders, says Kristman.
But that’s a hypothesis. We don’t know the actual reason for the health use.
When comparing with the baseline, however, the team saw the biggest increases in demand were related to mental disorders, tumours and circulatory system diseases. Given that the latter types of treatments aren’t generally associated with MTBI, Kristman thinks part of the rise in health-care usage is due to other health problems being detected during the course of treatment for the brain injury
We saw increased health-care use for things like cancer, as well as a greater increase in health-care use among people who weren’t seeing a doctor a lot before the injury. What those two findings suggest to us is that the brain injury caused people to see doctors, and that was when other problems were diagnosed, says Kristman.
For managers, return-to-work coordinators and other workplace parties, Kristman says her overall message is this: “Your workers may be back at work quickly after a mild brain injury, but some may have ongoing health issues that they need to monitor.”
The study was published in the March 2014 issue of the Archives of Physical Medicine and Rehabilitation. To read it, search for doi:10.1016/j.apmr.2013.08.296.
Source: At Work, Issue 78, Fall 2014: Institute for Work & Health, Toronto